title: Batman: Arkham Asylum

text: "Arkham Asylum" was called one of the best comic book superhero games ever made. "Edge" magazine said it was "by some distance the best superhero game of modern times", "IGN"s Greg Miller called it "the greatest comic book game of all time", and "Eurogamer"s Dan Whitehead called it "the best superhero game bar none", and wrote that it has "excellent visuals, a compelling story and superb voice acting." Whitehead also wrote, even without the iconic superhero, it would be a polished and engrossing game featuring compelling story and superb voice acting. "PSM3"s Andy Kelly wrote, "Rocksteady have struck the perfect balance of giving you the confident power of a superhero, but with enough weaknesses to make the game challenging; a remarkable feat of balancing and design". "Wired"s Chris Kohler said that the game's strength lies in its tight script and masterful acting, making what could be a generic game captivating. "1UP.com"s Thierry Nguyen gave the game an A−, stating that Rocksteady "manages to combine combat, stealth, storytelling, and cartoon voices into the best digital Batman simulator we've seen to date."


title: Batman: Arkham Asylum

text: Several reviewers compared "Arkham Asylum" to other gamesincluding "BioShock" for its ability to deliver a unique adventure and establish a connection with the game world, and its innovative ideas; "The Legend of Zelda" for its adventuring style; "Metroid" for its world layout; and "Resident Evil" and "Tomb Raider" for its classic action-adventuring that acts as a true hybrid of brawling, stealth, and platforming.


title: Batman: Arkham Asylum

text: The game world's design and the game's attention to detail were well received by critics. "Game Informer"s Andrew Reiner said the game's setting had a taut and mesmerizing atmosphere, and was a place of wonder and inexplicable horror. Miller called it the right mix of creepy and cool, and appreciated the gradual damage reflected on Batman's suit as the story progressed, but said that pixelated CGI and lip synching issues diminished the presentation. Whitehead said that the impressive animation makes Batman feel alive, but wrote that the world itself was lifeless and lacking in interactive objects. He criticized segments in which character logic was sacrificed for video game tropes, citing repeated use of poison gas and electric floors as obstacles.


title: Batman: Arkham Asylum

text: The combat system was well received for the simplicity of its implementation, allowing players to use it effectively without learning complex combinations of special moves, and the emphasis upon timing and flow to create fluid, graceful, and satisfyingly brutal attacks. Reviewers said that the combat remained challenging with the inclusion of more difficult-to-overcome enemies, and better use of combat was well incentivized without punishing those unable to master it. The design of stealth and the wide variety of methods available to disable enemy opponents were praised. "Computer and Video Games" Andy Robinson wrote that it is a "thinking man's stealth game" that is the centerpiece of the game, and "Edge" said that the stealth offering was thrilling. Others wrote about the way in which enemies react with fear to the elimination of their allies, but some reviewers criticized the AI for allowing Batman to easily escape when discovered, and for being oblivious to Batman's presence. Whitehead said that stealth was not as directly rewarding as combat, citing difficulty in controlling Batman at close quarters and the inconsistent contextual actions.


title: Batman: Arkham Asylum

text: "Arkham Asylum"s boss fights were criticized, with many reviewers labeling them as the game's biggest failing. Reviewers found that the battles often rely on old-fashioned, tedious, and repetitive game tropes that required the player to learn and repeat monotonous routinessome of which, in the case of Bane, had already been employed on lesser enemiesor to confront repetitive attack patterns and one-hit deaths. Reviewers generally agreed that the fights were anti-climactic to their build-up spectacle. The final boss fight with the Joker was singled out for vapid gameplay, a battle with Killer Croc was labeled boring and overly long, and the reviewers said these should not have been in the game. However, the fear toxin-induced hallucination segments of Scarecrow's battles were almost unanimously praised as some of the game's best and most cerebral moments for their fourth wall manipulation, subversion of the game's established narrative and expectations, and meta-textual influences that were compared to the battle against Psycho Mantis in 1998's "Metal Gear Solid", and 2002's "Eternal Darkness".


title: Batman: Arkham Asylum

text: The main voice castincluding Conroy as Batman, Sorkin as Harley Quinn, Valenza as Poison Ivy, and Wingert as Riddlerwas well received, but Hamill's performance received consistent praise, with reviewers commenting upon his excellent inflection and timing on a cackling, maniacal performance that steals the show. Nguyen said that Dini and Hamill's Joker was the best depiction of the character outside of "The Killing Joke" and Heath Ledger's incarnation in "The Dark Knight" (2008).


title: Batman: Arkham Asylum

text: Worldwide, the game sold nearly two million units in its first three weeks of release, and had sold 2.5 million by the end of September 2009. According to NPD Group, "Batman: Arkham Asylum" sold approximately 593,000 units in North America during the five tracked days following its release on August 25. By December 2009, the PlayStation 3 version of the game had outsold the Xbox 360 version by approximately 10,000 units despite multi-platform titles typically selling better on the Xbox 360 at the time. The exclusive content featuring the Joker as a playable character was cited as a possible reason for the success of the PlayStation 3 version. The game took two of the top five spots on the US software chart in its first week of release, and topped the UK all-format chart for two weeks. By October 2011, the game had sold 4.3million copies worldwide.


title: Batman: Arkham Asylum

text: At the 2009 Spike Video Game Awards, Rocksteady Studios won Studio of the Year, while the game received nominations for Best Action Adventure Game, Best Graphics, Best Voice for Hamill and Sorkin, respectively, Best Xbox 360 Game, and Game of the Year. As part of the Academy of Interactive Arts & Sciences (AIAS) 2009 awards, it won Outstanding Achievement awards for "Character Performance" (Mark Hamill as the Joker), "Game Design", and "Adapted Story", and was nominated for "Game of the Year", "Adventure Game of the Year", and Outstanding Achievement awards for "Animation", "Original Music Composition", and "Game Direction". At the 6th British Academy Video Games Awards, it won the awards for Best Game and Gameplay, and received nominations for Action, Original Score, Story, Use of Audio, Artistic Achievement, and the publicly voted GAME Award of 2009. It won Best Game Design at the 10th Game Developers Choice Awards, and was nominated for Game of the Year and Best Writing. It was also nominated for Best Sound Editing: Computer Entertainment for the 2010 Golden Reel Awards. The National Academy of Video Game Trade Reviewers awarded the game in the categories Game of the Year, Character Design, Control Design, Costume Design, Game Design, Sound Editing in a Game Cinema, Supp Performance in a Drama (Mark Hamill), Use of Sound and Game Sequel Action. The Official Xbox Magazine 2009 Game of the Year Awards awarded the game in two categories: Licensed Game of the Year and Developer of the Year (Rocksteady Studios). At the 2010 Develop Awards the game won in two categories: Best Use of a Licence or IP and In-House Studio (Rocksteady Studios). The game also gained two nominations (Audio of the Year and Best Dialogue) at the Game Audio Network Guild Awards. According to Metacritic, on all platforms, "Arkham Asylum" was tied with "God of War Collection" and "Forza Motorsport 3" as the fourth-highest-rated game of 2009. It was also the highest-rated Microsoft Windows game alongside "" and "Street Fighter IV", the third-highest-rated Xbox 360 game alongside "Forza Motorsport 3", and the fifth-highest-rated PlayStation 3 game alongside "FIFA 10" and "Killzone 2". At the Cody Awards the game won as Best Licensed Game and it was nominated in the categories Game of the Year, Best Graphics, Best Sound, Best Action-Adventure Game, Best Character (Batman).


title: Batman: Arkham Asylum

text: Several international video game websites and magazines labeled "Arkham Asylum" as their favourite Game of the Year and as their favourite Action/Adventure Game.


title: Batman: Arkham Asylum

text: "Batman: Arkham Asylum" appeared on several lists of the top video games of 2009. It was placed at number one by "The A.V. Club", number two by "CNET", "Time", "Eurogamer" and "CraveOnline", number three by "Complex", "IGN UK", "Joystiq", and "The Daily Telegraph", number four by CBC News and "Wired", and number five by "Gamasutra", "Entertainment Weekly" and "IGN Australia". "Game Informer" also included the game on its list of the 50 best videogames of 2009. "Giant Bomb" named it the 2009 Best Multiplatform Game, "GamesRadar" labeled it their Game of the Year ahead of "", and "Eurogamer" listed it on their "Games of 2009" series. "GameSpot" listed it as having the Best Atmosphere and the Best Use of a Creative License as part of their "Best Games of 2009" series, and at "IGN"s Best of 2009 Awards the game was awarded as Best PC Action Game and Best Xbox 360 story and it was nominated in the categories Award for Excellence in Sound (PS3), Best Action Game (PS3), Best Story (PS3), PS3 Game of the Year, Best Action Game (Xbox 360), Award for Excellence in Sound (Xbox 360), Xbox 360 Game of the Year, Award for Excellence in Sound (PC), Best Story (PC), PC Game of the Year. Always IGN named the game as Best Newcomer on its IGN Select Awards. "Newsarama" named the game as Best Super-hero Game 2009. "GameTrailers" named the title both Best Action-Adventure Game and Biggest Surprise of 2009. At The Escapist Awards the game was awarded as Game of the Year and it was nominated as Best Action-Adventure Game. The game was also awarded in the category Best Graphics by Feed Your Console and as Game of the Year by HollywoodJesus, Thunderbolt, VG-Reloaded and eGamer. In 2013, Eurogamer listed it as the 20th-best game of the contemporary console generation, "Game Informer" named it the second-best superhero game of all time, and GamingBolt listed it as the 89th-greatest game ever made. In 2014, "Empire" ranked it 28th on their list of the Greatest Video Game of All Time, behind "Arkham City" at number 12, and "IGN" listed it as the 22nd-best game of the console generation. In 2015, "PC Gamer" named it the 50th-best PC game, and IGN listed it as the 91st-Top Game of All Time. In 2017, "IGN" ranked the Scarecrow hallucination sequences 35th on their Top Unforgettable Video Game Moments list. In 2019, "The Guardian" placed the game 34th on its list of the 50 best videogames of the 21st century.


title: Batman: Arkham Asylum

text: "Arkham Asylum"s success launched a series of "Batman: Arkham" sequels, beginning in October 2011 with "". Set one year after the events of "Arkham Asylum", it is the direct sequel to the earlier game. It was developed by Rocksteady Studios, and distributed by Warner Bros. Interactive Entertainment. Manipulated by Hugo Strange, Gotham City's mayor Quincy Sharp closes Arkham Asylum and Blackgate prison, and converts a section of the city's slums into an open air prison known as Arkham City, to house all of Gotham's criminals. While a wary Batman watches over the activities in Arkham City, the Joker is dying from his consumption of Titan. The sequel introduces several new charactersincluding Hugo Strange, Robin, Catwoman, Ra's al Ghul, and Mr. Freezeto the series. A limited, six-issue comic series, also titled ""bridging the plots of "Arkham Asylum" and "Arkham City"was written by Paul Dini and featured art by Carlos D'Anda. The first issue was released on May 11, 2011. A third installment of the "Arkham" series (not developed by Rocksteady), "", was released in October 2013, featuring a story set before the events of "Arkham Asylum". A narrative sequel to "Arkham City", "", was released on June 23, 2015, and is the series' concluding chapter.


title: Batman: Arkham Asylum

text: Writer Grant Morrison said the game was the inspiration for their "Batman Incorporated" comic book. They said they wanted to "capture the feeling of the "Batman: Arkham Asylum" game ... When I played that game, it was the first time in my life where I actually felt what it is like to be Batman ...  We are now the heroes, and we can look through their eyes."


title: Marc Andreessen

text: Marc Lowell Andreessen ( ; born July 9, 1971) is an American entrepreneur, investor, and software engineer. He is the co-author of Mosaic, the first widely used web browser; co-founder of Netscape; and co-founder and general partner of Silicon Valley venture capital firm Andreessen Horowitz. He co-founded and later sold the software company Opsware to Hewlett-Packard. Andreessen is also a co-founder of Ning, a company that provides a platform for social networking websites. He sits on the board of directors of Meta Platforms. Andreessen was one of six inductees in the World Wide Web Hall of Fame announced at the First International Conference on the World-Wide Web in 1994.


title: Marc Andreessen

text: Andreessen was born in Cedar Falls, Iowa, and raised in New Lisbon, Wisconsin. He is the son of Patricia and Lowell Andreessen, who worked for a seed company. In December 1993, he received his bachelor's degree in computer science from the University of Illinois at Urbana–Champaign (UIUC). As an undergraduate, he interned twice at IBM in Austin, Texas. He worked in the AIX graphics software development group responsible for the MIT X Window implementation and ports of the 3D language APIs: SGI's Graphics Language (GL) and PHIGS. He also worked at the National Center for Supercomputing Applications (NCSA) at the University of Illinois, where he became familiar with Tim Berners-Lee's open standards for the World Wide Web. After being shown the ViolaWWW graphic web browser in late 1992, Andreessen and full-time salaried co-worker Eric Bina worked on creating a browser with integrated graphics that could be ported to a wide range of computers, including Windows. The result was the Mosaic web browser released in 1993.


title: Marc Andreessen

text: During his career, Andreesen has worked at Netscape, Opsware, founded Andreessen Horowitz and invested in many successful companies including, Facebook, Foursquare, GitHub, Pinterest, LinkedIn and Twitter.


title: Marc Andreessen

text: After his graduation from UIUC in 1993, Andreessen moved to California to work at Enterprise Integration Technologies. Andreessen then met with Jim Clark, the founder of Silicon Graphics, who had recently exited the firm. Clark believed the Mosaic browser had great commercial possibilities and suggested starting an Internet software company. Soon, Mosaic Communications Corporation was in business in Mountain View, California, with Andreessen as co-founder and vice president of technology. The University of Illinois was unhappy with the company's use of the Mosaic name, so Mosaic Communications changed its name to Netscape Communications, and its flagship Web browser was the Netscape Navigator.


title: Marc Andreessen

text: Netscape's IPO in 1995 put Andreessen into the public eye. He was featured on the cover of "Time" and other publications.


title: Marc Andreessen

text: Netscape was acquired in 1999 for $4.3 billion by AOL. Andreessen's hiring as its chief technology officer was contingent on the completion of the acquisition. The same year, he was named to the "MIT Technology Review" TR100 as one of the top 100 innovators in the world under the age of 35.


title: Marc Andreessen

text: After AOL acquired Netscape in late 1998, Andreessen went on to found Opsware with Ben Horowitz, Tim Howes, and In Sik Rhee. Originally named Loudcloud, the company provided computing, hosting and software services to consumer facing internet and e-commerce companies. Loudcloud sold its hosting business to EDS and changed its name to Opsware in 2003, with Andreessen serving as chairman. Acquired by Hewlett-Packard for $1.6 billion in 2007, it was one of the first companies to offer software as a service and to attempt cloud hosting.


title: Marc Andreessen

text: Between 2005 and 2009, Andreessen and longtime business partner Ben Horowitz separately invested a total of $80 million in 45 start-ups that included Twitter and Qik. The two became well known as super angel investors. On July 6, 2009, Andreessen and Horowitz announced their Silicon Valley venture-capital firm Andreessen Horowitz.


title: Marc Andreessen

text: The firm had been scrutinized among several other venture capital firms for lack of diversity in its workforce. In an interview with "New York Magazine", Andreessen stated the diversity discussion was valid, however, he believed the firm, as well as other venture capital firms of Silicon Valley, had been wrongly accused of intentionally discriminating against women and people of color. When asked specifically about the critique of ethnic and gender diversity in Silicon Valley, Andreessen responded that the issues were the "same thing."


title: Marc Andreessen

text: Begun with an initial capitalization of $300 million, within three years the firm grew to $2.7 billion under management across three funds. Andreessen Horowitz's portfolio holdings include Facebook, Foursquare, GitHub, Pinterest, Twitter, and Honor, Inc.


title: Marc Andreessen

text: On September 1, 2009, an investor group that included Andreessen Horowitz acquired a majority stake in Skype at a valuation of $2.75 billion, which was considered risky. The deal paid off in May 2011 when Microsoft bought Skype for $8.5 billion. In 2010, the firm assisted Silicon Valley attorney Ted Wang in creating the first free standardized seed round financing documents, the Series Seed Documents.


title: Marc Andreessen

text: Andreessen first joined the eBay board of directors in 2008, and served on it for six years. In October 2014, Andreessen announced his resignation from the board due to the company's decision to break off its online payments unit PayPal. The decision to cut ties with PayPal was a point of contention between Andreessen and investor Carl Icahn. Icahn advocated for the PayPal split while Andreessen opposed the spin off, resulting in public disputes. Andreessen was accused by Icahn of putting his own interests in front of what was best for shareholders. Icahn published his argument in an open letter that detailed alleged conflicts of interest in eBay's 2009 sale of Skype to a group of private investors, which included Andreessen's own firm.


title: Marc Andreessen

text: Andreessen advises the leaders of companies in which Andreessen Horowitz invests, including Mark Zuckerberg of Facebook and Mark Pincus of Zynga.


title: Marc Andreessen

text: Andreessen and Horowitz were ranked No. 6 on "Vanity Fair"s 2011 New Establishment List, no. 1 on CNET's 2011 most influential investors list and Nos. 2 and 21, respectively, on the 2012 "Forbes" Midas List of Tech's Top Investors.


title: Marc Andreessen

text: In April 2012, Andreessen and Andreessen Horowitz General Partners Ben Horowitz, Peter Levine, Jeff Jordan, John O'Farrell, and Scott Weiss pledged to donate half of their lifetime incomes from venture capital to charitable organizations.


title: Marc Andreessen

text: In 2012, Andreessen was named in the "Time" 100, an annual list of the 100 most influential people in the world assembled by "Time". His essay "Software is eating the world" has been influential and highly cited.


title: Marc Andreessen

text: In 2013, Andreessen was one of five Internet and Web pioneers awarded the inaugural Queen Elizabeth Prize for Engineering.


title: Marc Andreessen

text: In April 2020, early in the COVID-19 pandemic, Andreessen published an opinion article, "It's time to build", describing the United States' COVID-19 response and suggesting technological and cultural solutions to the problem.


title: Marc Andreessen

text: Andreessen cofounded and chaired Ning, the third company he established after Netscape and Loudcloud. In September 2011, it was announced that Ning had been sold to Mode Media for a reported price of $150 million. Andreessen joined Glam Media's board of directors following the sale.


title: Marc Andreessen

text: Andreessen serves on the board of Facebook, Hewlett Packard Enterprise, Kno, Stanford Hospital, Bump Technologies, Anki, Oculus VR, OpenGov, Dialpad, and TinyCo. Hewlett Packard Enterprise announced in February 2018 that board member Andreessen would not seek reelection at the 2018 Annual Meeting of Stockholders on April 4. In his time at Hewlett Packard, Andreessen had been partially blamed for some of the company's failures, including the recruiting of Leo Apotheker as well as the acquisitions of Autonomy and Palm.


title: Marc Andreessen

text: He is advisor to Asana and director of CollabNet. He is a proponent of Bitcoin and cryptocurrency. Andreessen is on an advisory board for Neom, the Saudi Arabian government’s plan to build a futuristic megacity in the desert.


title: Marc Andreessen

text: In February 2016, Andreessen posted a tweet in response to India's decision to apply net neutrality to Facebook's proposed project Free Basics. The tweet suggested that anti-colonialism had been catastrophic for the Indian people. Andreessen later deleted the tweet following criticism from Indians and non-Indians alike (including Facebook founder Mark Zuckerberg). Facebook spent millions advertising Free Basics to the Indian public. The project failed due to violations, setting preferential tariffs in accessing content and setting up a "walled garden" on the internet.


title: Marc Andreessen

text: In April 2016, Facebook shareholders filed a class action lawsuit to block Zuckerberg's plan to create a new class of non-voting shares. The lawsuit alleges Andreessen secretly coached Zuckerberg through a process to win board approval for the stock change, while Andreessen served as an independent board member representing stockholders.


title: Marc Andreessen

text: According to court documents, Andreessen shared information with Zuckerberg regarding their progress and concerns as well as helping Zuckerberg negotiate against shareholders. Court documents included transcripts of private texts between Zuckerberg and Andreessen.


title: Marc Andreessen

text: Andreessen married Laura Arrillaga in 2006. She is the founder of the Silicon Valley Social Venture Fund and daughter of Silicon Valley real estate billionaire John Arrillaga. They have one son together.


title: Marc Andreessen

text: In 2012, Andreessen expressed some support for Republican candidate Mitt Romney. During the 2016 primary season, he endorsed Republican candidate Carly Fiorina, but after Fiorina dropped out of the race, Andreessen switched his endorsement to the Democratic nominee Hillary Clinton, citing the Republican nominee Donald Trump's immigration stance.


title: Marc Andreessen

text: In 2021, he and his wife bought a property in Malibu for $177 million from Serge and Florence Azria. This was the highest price paid for a California property at that time.


title: Marc Andreessen

text: In 2022, Andreessen advocated against the construction of 131 multifamily housing units in their affluent Atherton, California town. In a letter, Andreessen and his wife wrote that they opposed permitting more than one house on a single acre of land. Andreessen's comments sparked criticisms of hypocrisy, as he had previously argued for increased housing supply, in particular in California.


title: Marc Andreessen

text: In 2022, Andreessen's plane was returning to Los Angeles when the nose gear failed to operate before landing. After circling the runway several times, the plane landed safely without the nose gear.


title: Mercator projection

text: The Mercator projection () is a cylindrical map projection presented by Flemish geographer and cartographer Gerardus Mercator in 1569. It became the standard map projection for navigation because it is unique in representing north as up and south as down everywhere while preserving local directions and shapes. The map is thereby conformal. As a side effect, the Mercator projection inflates the size of objects away from the equator. This inflation is very small near the equator but accelerates with increasing latitude to become infinite at the poles. As a result, landmasses such as Greenland, Antarctica and Russia appear far larger than they actually are relative to landmasses near the equator, such as Central Africa.


title: Mercator projection

text: There is some controversy over the origins of the Mercator. German polymath Erhard Etzlaub engraved miniature "compass maps" (about 10×8 cm) of Europe and parts of Africa that spanned latitudes 0°–67° to allow adjustment of his portable pocket-size sundials. The projection found on these maps, dating to 1511, was stated by Snyder in 1987 to be the same projection as Mercator's. However, given the geometry of a sundial, these maps may well have been based on the similar central cylindrical projection, a limiting case of the gnomonic projection, which is the basis for a sundial. Snyder amends his assessment to "a similar projection" in 1994.


title: Mercator projection

text: Joseph Needham, a historian of China, wrote that the Chinese developed the Mercator projection hundreds of years before Mercator did, using it in star charts during the Song Dynasty. However, this was a simple, and common, case of misidentification. The projection in use was the equirectangular projection.


title: Mercator projection

text: Portuguese mathematician and cosmographer Pedro Nunes first described the mathematical principle of the loxodrome and its use in marine navigation. In 1537, he proposed constructing a nautical atlas composed of several large-scale sheets in the cylindrical equidistant projection as a way to minimize distortion of directions. If these sheets were brought to the same scale and assembled, they would approximate the Mercator projection.


title: Mercator projection

text: In 1569, Gerhard Kremer, known by his trade name Gerardus Mercator, announced a new projection by publishing a large planispheric map measuring and printed in eighteen separate sheets. Mercator titled the map : "A new and augmented description of Earth corrected for the use of sailors". This title, along with an elaborate explanation for using the projection that appears as a section of text on the map, shows that Mercator understood exactly what he had achieved and that he intended the projection to aid navigation. Mercator never explained the method of construction or how he arrived at it. Various hypotheses have been tendered over the years, but in any case Mercator's friendship with Pedro Nunes and his access to the loxodromic tables Nunes created likely aided his efforts.


title: Mercator projection

text: English mathematician Edward Wright published the first accurate tables for constructing the projection in 1599 and, in more detail, in 1610, calling his treatise "Certaine Errors in Navigation". The first mathematical formulation was publicized around 1645 by a mathematician named Henry Bond (c. 1600–1678). However, the mathematics involved were developed but never published by mathematician Thomas Harriot starting around 1589.


title: Mercator projection

text: The development of the Mercator projection represented a major breakthrough in the nautical cartography of the 16th century. However, it was much ahead of its time, since the old navigational and surveying techniques were not compatible with its use in navigation. Two main problems prevented its immediate application: the impossibility of determining the longitude at sea with adequate accuracy and the fact that magnetic directions, instead of geographical directions, were used in navigation. Only in the middle of the 18th century, after the marine chronometer was invented and the spatial distribution of magnetic declination was known, could the Mercator projection be fully adopted by navigators.


title: Mercator projection

text: Despite those position-finding limitations, the Mercator projection can be found in many world maps in the centuries following Mercator's first publication. However, it did not begin to dominate world maps until the 19th century, when the problem of position determination had been largely solved. Once the Mercator became the usual projection for commercial and educational maps, it came under persistent criticism from cartographers for its unbalanced representation of landmasses and its inability to usefully show the polar regions.


title: Mercator projection

text: The criticisms leveled against inappropriate use of the Mercator projection resulted in a flurry of new inventions in the late 19th and early 20th century, often directly touted as alternatives to the Mercator. Due to these pressures, publishers gradually reduced their use of the projection over the course of the 20th century. However, the advent of Web mapping gave the projection an abrupt resurgence in the form of the Web Mercator projection.


title: Mercator projection

text: Today, the Mercator can be found in marine charts, occasional world maps, and Web mapping services, but commercial atlases have largely abandoned it, and wall maps of the world can be found in many alternative projections. Google Maps, which relied on it since 2005, still uses it for local-area maps but dropped the projection from desktop platforms in 2017 for maps that are zoomed out of local areas. Many other online mapping services still exclusively use the Web Mercator.


title: Mercator projection

text: As in all cylindrical projections, parallels and meridians on the Mercator are straight and perpendicular to each other. In accomplishing this, the unavoidable east–west stretching of the map, which increases as distance away from the equator increases, is accompanied in the Mercator projection by a corresponding north–south stretching, so that at every point location the east–west scale is the same as the north–south scale, making it a conformal map projection. Conformal projections preserve angles around all locations.


title: Mercator projection

text: Because the linear scale of a Mercator map increases with latitude, it distorts the size of geographical objects far from the equator and conveys a distorted perception of the overall geometry of the planet. At latitudes greater than 70° north or south the Mercator projection is practically unusable, because the linear scale becomes infinitely large at the poles. A Mercator map can therefore never fully show the polar areas (as long as the projection is based on a cylinder centered on the Earth's rotation axis; see the transverse Mercator projection for another application).


title: Mercator projection

text: The Mercator projection maps all lines with constant bearing (rhumbs (mathematically known as loxodromes—those making constant angles with the meridians) to straight lines. The two properties, conformality and straight rhumb lines, make this projection uniquely suited to marine navigation: courses and bearings are measured using wind roses or protractors, and the corresponding directions are easily transferred from point to point, on the map, with the help of a parallel ruler (for example).


title: Mercator projection

text: The Mercator projection is often compared to and confused with the central cylindrical projection, which is the result of projecting points from the sphere onto a tangent cylinder along straight radial lines, as if from a light source placed at the Earth's center. Both have extreme distortion far from the equator and cannot show the poles. However, they are different projections and have different properties.


title: Mercator projection

text: As on all map projections, shapes or sizes are distortions of the true layout of the Earth's surface.


title: Mercator projection

text: Because of great land area distortions, some consider the projection unsuitable for general world maps. Mercator himself used the equal-area sinusoidal projection to show relative areas. However, despite such distortions, the Mercator projection was, especially in the late 19th and early 20th centuries, perhaps the most common projection used in world maps, despite being much criticized for this use.


title: Mercator projection

text: Because of its very common usage, the Mercator projection has been supposed to have influenced people's view of the world, and because it shows countries near the Equator as too small when compared to those of Europe and North America, it has been supposed to cause people to consider those countries as less important. As a result of these criticisms, modern atlases no longer use the Mercator projection for world maps or for areas distant from the equator, preferring other cylindrical projections, or forms of equal-area projection. The Mercator projection is, however, still commonly used for areas near the equator where distortion is minimal. It is also frequently found in maps of time zones.


title: Mercator projection

text: Arno Peters stirred controversy beginning in 1972 when he proposed what is now usually called the Gall–Peters projection to remedy the problems of the Mercator, claiming it to be his own original work without referencing prior work by cartographers such as Gall's work from 1855. The projection he promoted is a specific parameterization of the cylindrical equal-area projection. In response, a 1989 resolution by seven North American geographical groups disparaged using cylindrical projections for general-purpose world maps, which would include both the Mercator and the Gall–Peters.


title: Mercator projection

text: Practically every marine chart in print is based on the Mercator projection due to its uniquely favorable properties for navigation. It is also commonly used by street map services hosted on the Internet, due to its uniquely favorable properties for local-area maps computed on demand. Mercator projections were also important in the mathematical development of plate tectonics in the 1960s.


title: Mercator projection

text: The Mercator projection was designed for use in marine navigation because of its unique property of representing any course of constant bearing as a straight segment. Such a course, known as a rhumb (or, mathematically, a loxodrome) is preferred in marine navigation because ships can sail in a constant compass direction, reducing the difficult, error-prone course corrections that otherwise would be needed frequently when sailing a different course. For distances small compared to the radius of the Earth, the difference between the rhumb and the technically shortest course, a great circle segment, is negligible, and even for longer distances, the simplicity of the constant bearing makes it attractive. As observed by Mercator, on such a course, the ship would not arrive by the shortest route, but it will surely arrive. Sailing a rhumb meant that all that the sailors had to do was keep a constant course as long as they knew where they were when they started, where they intended to be when they finished, and had a map in Mercator projection that correctly showed those two coordinates.


title: Mercator projection

text: Many major online street mapping services (Bing Maps, Google Maps, Mapbox, MapQuest, OpenStreetMap, Yahoo! Maps, and others) use a variant of the Mercator projection for their map images called Web Mercator or Google Web Mercator. Despite its obvious scale variation at small scales, the projection is well-suited as an interactive world map that can be zoomed seamlessly to large-scale (local) maps, where there is relatively little distortion due to the variant projection's near-conformality.


title: Mercator projection

text: The major online street mapping services' tiling systems display most of the world at the lowest zoom level as a single square image, excluding the polar regions by truncation at latitudes of "φ" = ±85.05113°. (See below.) Latitude values outside this range are mapped using a different relationship that does not diverge at "φ" = ±90°.


title: Mercator projection

text: Although the surface of Earth is best modelled by an oblate ellipsoid of revolution, for small scale maps the ellipsoid is approximated by a sphere of radius "a", where "a" is approximately 6,371 km. This spherical approximation of Earth can be modelled by a smaller sphere of radius "R", called the "globe" in this section. The globe determines the scale of the map. The various cylindrical projections specify how the geographic detail is transferred from the globe to a cylinder tangential to it at the equator. The cylinder is then unrolled to give the planar map. The fraction is called the representative fraction (RF) or the principal scale of the projection. For example, a Mercator map printed in a book might have an equatorial width of 13.4 cm corresponding to a globe radius of 2.13 cm and an RF of approximately (M is used as an abbreviation for 1,000,000 in writing an RF) whereas Mercator's original 1569 map has a width of 198 cm corresponding to a globe radius of 31.5 cm and an RF of about .


title: Mercator projection

text: A cylindrical map projection is specified by formulae linking the geographic coordinates of latitude "φ" and longitude "λ" to Cartesian coordinates on the map with origin on the equator and "x"-axis along the equator. By construction, all points on the same meridian lie on the same "generator" of the cylinder at a constant value of "x", but the distance "y" along the generator (measured from the equator) is an arbitrary function of latitude, "y"("φ"). In general this function does not describe the geometrical projection (as of light rays onto a screen) from the centre of the globe to the cylinder, which is only one of an unlimited number of ways to conceptually project a cylindrical map.


title: Mercator projection

text: Since the cylinder is tangential to the globe at the equator, the scale factor between globe and cylinder is unity on the equator but nowhere else. In particular since the radius of a parallel, or circle of latitude, is "R" cos "φ", the corresponding parallel on the map must have been stretched by a factor of . This scale factor on the parallel is conventionally denoted by "k" and the corresponding scale factor on the meridian is denoted by "h".


title: Mercator projection

text: The Mercator projection is determined by the requirement that the projection be conformal. One implication of this is the "isotropy of scale factors", which means that the point scale factor is independent of direction, so that small shapes are preserved by the projection. This implies that the vertical scale factor, "h", equals the horizontal scale factor, "k". Since "k" = , so must "h".


title: Mercator projection

text: The graph shows the variation of this scale factor with latitude. Some numerical values are listed below.


title: Mercator projection

text: The area scale factor is the product of the parallel and meridian scales . For Greenland, taking 73° as a median latitude, "hk" = 11.7. For Australia, taking 25° as a median latitude, "hk" = 1.2. For Great Britain, taking 55° as a median latitude, "hk" = 3.04.


title: Mercator projection

text: The classic way of showing the distortion inherent in a projection is to use Tissot's indicatrix. Nicolas Tissot noted that the scale factors at a point on a map projection, specified by the numbers "h" and "k", define an ellipse at that point. For cylindrical projections, the axes of the ellipse are aligned to the meridians and parallels. For the Mercator projection, "h" = "k", so the ellipses degenerate into circles with radius proportional to the value of the scale factor for that latitude. These circles are rendered on the projected map with extreme variation in size, indicative of Mercator's scale variations.


title: Mercator projection

text: As discussed above, the isotropy condition implies that "h" = "k" = . Consider a point on the globe of radius "R" with longitude "λ" and latitude "φ". If "φ" is increased by an infinitesimal amount, "dφ", the point moves "R" "dφ" along a meridian of the globe of radius "R", so the corresponding change in "y", "dy", must be "hR" "dφ" = "R" sec "φ" "dφ". Therefore "y′"("φ") = "R" sec "φ". Similarly, increasing "λ" by "dλ" moves the point "R" cos "φ" "dλ" along a parallel of the globe, so "dx" = "kR" cos "φ" "dλ" = "R" "dλ". That is, "x′"("λ") = "R". Integrating the equations


title: Mercator projection

text: with "x"("λ") = 0 and "y"(0) = 0, gives "x(λ)" and "y(φ)". The value "λ" is the longitude of an arbitrary central meridian that is usually, but not always, that of Greenwich (i.e., zero). The angles "λ" and "φ" are expressed in radians. By the integral of the secant function,


title: Mercator projection

text: The function "y"("φ") is plotted alongside "φ" for the case "R" = 1: it tends to infinity at the poles. The linear "y"-axis values are not usually shown on printed maps; instead some maps show the non-linear scale of latitude values on the right. More often than not the maps show only a graticule of selected meridians and parallels.


title: Mercator projection

text: The expression on the right of the second equation defines the Gudermannian function; i.e., "φ" = gd(): the direct equation may therefore be written as "y" = "R"·gd("φ").


title: Mercator projection

text: The above formulae are written in terms of the globe radius "R". It is often convenient to work directly with the map width "W" = 2"R". For example, the basic transformation equations become


title: Mercator projection

text: The ordinate "y" of the Mercator projection becomes infinite at the poles and the map must be truncated at some latitude less than ninety degrees. This need not be done symmetrically. Mercator's original map is truncated at 80°N and 66°S with the result that European countries were moved toward the centre of the map. The aspect ratio of his map is = 1.65. Even more extreme truncations have been used: a was truncated at approximately 76°N and 56°S, an aspect ratio of 1.97.


title: Mercator projection

text: Much Web-based mapping uses a zoomable version of the Mercator projection with an aspect ratio of one. In this case the maximum latitude attained must correspond to "y" = ±, or equivalently  = . Any of the inverse transformation formulae may be used to calculate the corresponding latitudes:


title: Mercator projection

text: The relations between "y"("φ") and properties of the projection, such as the transformation of angles and the variation in scale, follow from the geometry of corresponding "small" elements on the globe and map. The figure below shows a point P at latitude "φ" and longitude "λ" on the globe and a nearby point Q at latitude "φ" + "δφ" and longitude "λ" + "δλ". The vertical lines PK and MQ are arcs of meridians of length "Rδφ". The horizontal lines PM and KQ are arcs of parallels of length "R"(cos "φ")"δλ". The corresponding points on the projection define a rectangle of width "δx" and height "δy".


title: Mercator projection

text: Since the meridians are mapped to lines of constant "x", we must have and "δx" = "Rδλ", ("λ" in radians). Therefore, in the limit of infinitesimally small elements


title: Mercator projection

text: In the case of the Mercator projection, "y"'("φ") = "R" sec "φ", so this gives us "h" = "k" and "α" = "β". The fact that "h" = "k" is the isotropy of scale factors discussed above. The fact that "α" = "β" reflects another implication of the mapping being conformal, namely the fact that a sailing course of constant azimuth on the globe is mapped into the same constant grid bearing on the map.


title: Mercator projection

text: Converting ruler distance on the Mercator map into true (great circle) distance on the sphere is straightforward along the equator but nowhere else. One problem is the variation of scale with latitude, and another is that straight lines on the map (rhumb lines), other than the meridians or the equator, do not correspond to great circles.


title: Mercator projection

text: The distinction between rhumb (sailing) distance and great circle (true) distance was clearly understood by Mercator. (See Legend 12 on the 1569 map.) He stressed that the rhumb line distance is an acceptable approximation for true great circle distance for courses of short or moderate distance, particularly at lower latitudes. He even quantifies his statement: "When the great circle distances which are to be measured in the vicinity of the equator do not exceed 20 degrees of a great circle, or 15 degrees near Spain and France, or 8 and even 10 degrees in northern parts it is convenient to use rhumb line distances".


title: Mercator projection

text: For a ruler measurement of a "short" line, with midpoint at latitude "φ", where the scale factor is "k" = sec "φ" = :


title: Mercator projection

text: With radius and great circle circumference equal to 6,371 km and 40,030 km respectively an RF of , for which "R" = 2.12 cm and "W" = 13.34 cm, implies that a ruler measurement of 3 mm. in any direction from a point on the equator corresponds to approximately 900 km. The corresponding distances for latitudes 20°, 40°, 60° and 80° are 846 km, 689 km, 450 km and 156 km respectively.


title: Mercator projection

text: Scale is unity on the equator (for a non-secant projection). Therefore, interpreting ruler measurements on the equator is simple:


title: Mercator projection

text: This is not the shortest distance between the chosen endpoints on the parallel because a parallel is not a great circle. The difference is small for short distances but increases as "λ", the longitudinal separation, increases. For two points, A and B, separated by 10° of longitude on the parallel at 60° the distance along the parallel is approximately 0.5 km greater than the great circle distance. (The distance AB along the parallel is ("a" cos "φ") "λ". The length of the chord AB is 2("a" cos "φ") sin . This chord subtends an angle at the centre equal to 2arcsin(cos "φ" sin ) and the great circle distance between A and B is 2"a" arcsin(cos "φ" sin ).) In the extreme case where the longitudinal separation is 180°, the distance along the parallel is one half of the circumference of that parallel; i.e., 10,007.5 km. On the other hand, the geodesic between these points is a great circle arc through the pole subtending an angle of 60° at the center: the length of this arc is one sixth of the great circle circumference, about 6,672 km. The difference is 3,338 km so the ruler distance measured from the map is quite misleading even after correcting for the latitude variation of the scale factor.


title: Mercator projection

text: A meridian of the map is a great circle on the globe but the continuous scale variation means ruler measurement alone cannot yield the true distance between distant points on the meridian. However, if the map is marked with an accurate and finely spaced latitude scale from which the latitude may be read directly—as is the case for the Mercator 1569 world map (sheets 3, 9, 15) and all subsequent nautical charts—the meridian distance between two latitudes "φ" and "φ" is simply


title: Mercator projection

text: If the latitudes of the end points cannot be determined with confidence then they can be found instead by calculation on the ruler distance. Calling the ruler distances of the end points on the map meridian as measured from the equator "y" and "y", the true distance between these points on the sphere is given by using any one of the inverse Mercator formulæ:


title: Mercator projection

text: where "R" may be calculated from the width "W" of the map by "R" = . For example, on a map with "R" = 1 the values of "y" = 0, 1, 2, 3 correspond to latitudes of "φ" = 0°, 50°, 75°, 84° and therefore the successive intervals of 1 cm on the map correspond to latitude intervals on the globe of 50°, 25°, 9° and distances of 5,560 km, 2,780 km, and 1,000 km on the Earth.


title: Mercator projection

text: A straight line on the Mercator map at angle "α" to the meridians is a rhumb line. When "α" =  or the rhumb corresponds to one of the parallels; only one, the equator, is a great circle. When "α" = 0 or it corresponds to a meridian great circle (if continued around the Earth). For all other values it is a spiral from pole to pole on the globe intersecting all meridians at the same angle, and is thus not a great circle. This section discusses only the last of these cases.


title: Mercator projection

text: If "α" is neither 0 nor then the above figure of the infinitesimal elements shows that the length of an infinitesimal rhumb line on the sphere between latitudes "φ"; and "φ" + "δφ" is "a" sec "α" "δφ". Since "α" is constant on the rhumb this expression can be integrated to give, for finite rhumb lines on the Earth:


title: Mercator projection

text: Once again, if Δ"φ" may be read directly from an accurate latitude scale on the map, then the rhumb distance between map points with latitudes "φ" and "φ" is given by the above. If there is no such scale then the ruler distances between the end points and the equator, "y" and "y", give the result via an inverse formula:


title: Mercator projection

text: These formulæ give rhumb distances on the sphere which may differ greatly from true distances whose determination requires more sophisticated calculations.


title: Mercator projection

text: When the Earth is modelled by a spheroid (ellipsoid of revolution) the Mercator projection must be modified if it is to remain conformal. The transformation equations and scale factor for the non-secant version are


title: Mercator projection

text: The scale factor is unity on the equator, as it must be since the cylinder is tangential to the ellipsoid at the equator. The ellipsoidal correction of the scale factor increases with latitude but it is never greater than "e", a correction of less than 1%. (The value of "e" is about 0.006 for all reference ellipsoids.) This is much smaller than the scale inaccuracy, except very close to the equator. Only accurate Mercator projections of regions near the equator will necessitate the ellipsoidal corrections.


title: Accuracy and precision

text: Accuracy is how close a given set of measurements (observations or readings) are to their "true value", while precision is how close the measurements are to each other.


title: Accuracy and precision

text: In other words, "precision" is a description of "random errors", a measure of statistical variability. "Accuracy" has two definitions:


title: Accuracy and precision

text: In the first, more common definition of "accuracy" above, the concept is independent of "precision", so a particular set of data can be said to be accurate, precise, both, or neither.


title: Accuracy and precision

text: In simpler terms, given a statistical sample or set of data points from repeated measurements of the same quantity, the sample or set can be said to be "accurate" if their average is close to the true value of the quantity being measured, while the set can be said to be "precise" if their standard deviation is relatively small.


title: Accuracy and precision

text: In the fields of science and engineering, the accuracy of a measurement system is the degree of closeness of measurements of a quantity to that quantity's true value. The precision of a measurement system, related to reproducibility and repeatability, is the degree to which repeated measurements under unchanged conditions show the same results. Although the two words precision and accuracy can be synonymous in colloquial use, they are deliberately contrasted in the context of the scientific method.


title: Accuracy and precision

text: The field of statistics, where the interpretation of measurements plays a central role, prefers to use the terms "bias" and "variability" instead of accuracy and precision: bias is the amount of inaccuracy and variability is the amount of imprecision.


title: Accuracy and precision

text: A measurement system can be accurate but not precise, precise but not accurate, neither, or both. For example, if an experiment contains a systematic error, then increasing the sample size generally increases precision but does not improve accuracy. The result would be a consistent yet inaccurate string of results from the flawed experiment. Eliminating the systematic error improves accuracy but does not change precision.


title: Accuracy and precision

text: A measurement system is considered "valid" if it is both "accurate" and "precise". Related terms include "bias" (non-random or directed effects caused by a factor or factors unrelated to the independent variable) and "error" (random variability).


title: Accuracy and precision

text: The terminology is also applied to indirect measurements—that is, values obtained by a computational procedure from observed data.


title: Accuracy and precision

text: In addition to accuracy and precision, measurements may also have a measurement resolution, which is the smallest change in the underlying physical quantity that produces a response in the measurement.


title: Accuracy and precision

text: In numerical analysis, accuracy is also the nearness of a calculation to the true value; while precision is the resolution of the representation, typically defined by the number of decimal or binary digits.


title: Accuracy and precision

text: In military terms, accuracy refers primarily to the accuracy of fire ("justesse de tir"), the precision of fire expressed by the closeness of a grouping of shots at and around the centre of the target.


title: Accuracy and precision

text: In industrial instrumentation, accuracy is the measurement tolerance, or transmission of the instrument and defines the limits of the errors made when the instrument is used in normal operating conditions.


title: Accuracy and precision

text: Ideally a measurement device is both accurate and precise, with measurements all close to and tightly clustered around the true value. The accuracy and precision of a measurement process is usually established by repeatedly measuring some traceable reference standard. Such standards are defined in the International System of Units (abbreviated SI from French: "Système international d'unités") and maintained by national standards organizations such as the National Institute of Standards and Technology in the United States.


title: Accuracy and precision

text: This also applies when measurements are repeated and averaged. In that case, the term standard error is properly applied: the precision of the average is equal to the known standard deviation of the process divided by the square root of the number of measurements averaged. Further, the central limit theorem shows that the probability distribution of the averaged measurements will be closer to a normal distribution than that of individual measurements.


title: Accuracy and precision

text: A common convention in science and engineering is to express accuracy and/or precision implicitly by means of significant figures. Where not explicitly stated, the margin of error is understood to be one-half the value of the last significant place. For instance, a recording of 843.6 m, or 843.0 m, or 800.0 m would imply a margin of 0.05 m (the last significant place is the tenths place), while a recording of 843 m would imply a margin of error of 0.5 m (the last significant digits are the units).


title: Accuracy and precision

text: A reading of 8,000 m, with trailing zeros and no decimal point, is ambiguous; the trailing zeros may or may not be intended as significant figures. To avoid this ambiguity, the number could be represented in scientific notation: 8.0 × 10 m indicates that the first zero is significant (hence a margin of 50 m) while 8.000 × 10 m indicates that all three zeros are significant, giving a margin of 0.5 m. Similarly, one can use a multiple of the basic measurement unit: 8.0 km is equivalent to 8.0 × 10 m. It indicates a margin of 0.05 km (50 m). However, reliance on this convention can lead to false precision errors when accepting data from sources that do not obey it. For example, a source reporting a number like 153,753 with precision +/- 5,000 looks like it has precision +/- 0.5. Under the convention it would have been rounded to 154,000.


title: Accuracy and precision

text: Alternatively, in a scientific context, if it is desired to indicate the margin of error with more precision, one can use a notation such as 7.54398(23) × 10 m, meaning a range of between 7.54375 and 7.54421 × 10 m.


title: Accuracy and precision

text: In engineering, precision is often taken as three times Standard Deviation of measurements taken, representing the range that 99.73% of measurements can occur within. For example, an ergonomist measuring the human body can be confident that 99.73% of their extracted measurements fall within ± 0.7 cm - if using the GRYPHON processing system - or ± 13 cm - if using unprocessed data.


title: Accuracy and precision

text: A shift in the meaning of these terms appeared with the publication of the ISO 5725 series of standards in 1994, which is also reflected in the 2008 issue of the "BIPM International Vocabulary of Metrology" (VIM), items 2.13 and 2.14.


title: Accuracy and precision

text: According to ISO 5725-1, the general term "accuracy" is used to describe the closeness of a measurement to the true value. When the term is applied to sets of measurements of the same measurand, it involves a component of random error and a component of systematic error. In this case trueness is the closeness of the mean of a set of measurement results to the actual (true) value and precision is the closeness of agreement among a set of results.


title: Accuracy and precision

text: ISO 5725-1 and VIM also avoid the use of the term "bias", previously specified in BS 5497-1, because it has different connotations outside the fields of science and engineering, as in medicine and law.


title: Accuracy and precision

text: "Accuracy" is also used as a statistical measure of how well a binary classification test correctly identifies or excludes a condition. That is, the accuracy is the proportion of correct predictions (both true positives and true negatives) among the total number of cases examined. As such, it compares estimates of pre- and post-test probability. To make the context clear by the semantics, it is often referred to as the "Rand accuracy" or "Rand index". It is a parameter of the test.


title: Accuracy and precision

text: Note that, in this context, the concepts of trueness and precision as defined by ISO 5725-1 are not applicable. One reason is that there is not a single “true value” of a quantity, but rather two possible true values for every case, while accuracy is an average across all cases and therefore takes into account both values. However, the term "precision" is used in this context to mean a different metric originating from the field of information retrieval (see below).


title: Accuracy and precision

text: When computing accuracy in multiclass classification, accuracy is simply the fraction of correct classifications:


title: Accuracy and precision

text: This is usually expressed as a percentage. For example, if a classifier makes ten predictions and nine of them are correct, the accuracy is 90%.


title: Accuracy and precision

text: Accuracy is also called top-1 accuracy to distinguish it from top-5 accuracy, common in convolutional neural network evaluation. To evaluate top-5 accuracy, the classifier must provide relative likelihoods for each class. When these are sorted, a classification is considered correct if the correct classification falls anywhere within the top 5 predictions made by the network. Top-5 accuracy was popularized by the ImageNet challenge. It is usually higher than top-1 accuracy, as any correct predictions in the 2nd through 5th positions will not improve the top-1 score, but do improve the top-5 score.


title: Accuracy and precision

text: In psychometrics and psychophysics, the term "accuracy" is interchangeably used with validity and "constant error". "Precision" is a synonym for reliability and "variable error". The validity of a measurement instrument or psychological test is established through experiment or correlation with behavior. Reliability is established with a variety of statistical techniques, classically through an internal consistency test like Cronbach's alpha to ensure sets of related questions have related responses, and then comparison of those related question between reference and target population.


title: Accuracy and precision

text: In logic simulation, a common mistake in evaluation of accurate models is to compare a logic simulation model to a transistor circuit simulation model. This is a comparison of differences in precision, not accuracy. Precision is measured with respect to detail and accuracy is measured with respect to reality.


title: Accuracy and precision

text: Information retrieval systems, such as databases and web search engines, are evaluated by many different metrics, some of which are derived from the confusion matrix, which divides results into true positives (documents correctly retrieved), true negatives (documents correctly not retrieved), false positives (documents incorrectly retrieved), and false negatives (documents incorrectly not retrieved). Commonly used metrics include the notions of precision and recall. In this context, precision is defined as the fraction of retrieved documents which are relevant to the query (true positives divided by true+false positives), using a set of ground truth relevant results selected by humans. Recall is defined as the fraction of relevant documents retrieved compared to the total number of relevant documents (true positives divided by true positives+false negatives). Less commonly, the metric of accuracy is used, is defined as the total number of correct classifications (true positives plus true negatives) divided by the total number of documents.


title: Accuracy and precision

text: None of these metrics take into account the ranking of results. Ranking is very important for web search engines because readers seldom go past the first page of results, and there are too many documents on the web to manually classify all of them as to whether they should be included or excluded from a given search. Adding a cutoff at a particular number of results takes ranking into account to some degree. The measure precision at k, for example, is a measure of precision looking only at the top ten (k=10) search results. More sophisticated metrics, such as discounted cumulative gain, take into account each individual ranking, and are more commonly used where this is important.


title: Accuracy and precision

text: In cognitive systems, accuracy and precision is used to characterize and measure results of a cognitive process performed by biological or artificial entities where a cognitive process is a transformation of data, information, knowledge, or wisdom to a higher-valued form. (DIKW Pyramid) Sometimes, a cognitive process produces exactly the intended or desired output but sometimes produces output far from the intended or desired. Furthermore, repetitions of a cognitive process do not always produce the same output. "Cognitive accuracy" (C) is the propensity of a cognitive process to produce the intended or desired output. "Cognitive precision" (C) is the propensity of a cognitive process to produce only the intended or desired output. To measure augmented cognition in human/cog ensembles, where one or more humans work collaboratively with one or more cognitive systems (cogs), increases in cognitive accuracy and cognitive precision assist in measuring the degree of cognitive augmentation.


title: Kundalini

text: In Hinduism, Kundalini (, ) is a form of divine feminine energy (or "Shakti") believed to be located at the base of the spine, in the "muladhara". It is an important concept in , where it is believed to be a force or power associated with the divine feminine or the formless aspect of the Goddess. This energy in the body, when cultivated and awakened through tantric practice, is believed to lead to spiritual liberation. Kuṇḍalinī is associated with Parvati or Adi Parashakti, the supreme being in Shaktism; and with the goddesses Bhairavi and Kubjika. The term, along with practices associated with it, was adopted into Hatha yoga in the 9th century. It has since then been adopted into other forms of Hinduism as well as modern spirituality and New age thought.


title: Kundalini

text: Kuṇḍalinī awakenings are said to occur by a variety of methods. Many systems of yoga focus on awakening Kuṇḍalinī through: meditation; pranayama breathing; the practice of asana and chanting of mantras. Kundalini Yoga is influenced by Shaktism and Tantra schools of Hinduism. It derives its name from its focus upon the awakening of kundalini energy through regular practice of Mantra, Tantra, Yantra, Asanas or Meditation. The Kuṇḍalinī experience is frequently reported to be a distinct feeling of electric current running along the spine.


title: Kundalini

text: The concept of Kuṇḍalinī is mentioned in the Upanishads (9th – 7th centuries BCE). The Sanskrit adjective ' means "circular, annular". It is mentioned as a noun for "snake" (in the sense of "coiled") in the 12th-century "Rajatarangini" chronicle (I.2). ' (a noun meaning "bowl, water-pot" is found as the name of a Nāga (serpent deity) in Mahabharata 1.4828). The 8th-century "Tantrasadbhava Tantra" uses the term "kundalī", glossed by David Gordon White as "she who is ring-shaped".


title: Kundalini

text: The use of "kuṇḍalī" as a name for Goddess Durga (a form of Shakti) appears often in Tantrism and Shaktism from as early as the 11th century in the "Śaradatilaka". It was adopted as a technical term in Hatha yoga during the 15th century, and became widely used in the Yoga Upanishads by the 16th century. Eknath Easwaran has paraphrased the term as "the coiled power", a force which ordinarily rests at the base of the spine, described as being "coiled there like a serpent".


title: Kundalini

text: Kuṇḍalinī arose as a central concept in , especially among the Śākta cults like the Kaula. In these Tantric traditions, Kuṇḍalinī is "the innate intelligence of embodied Consciousness". The first possible mention of the term is in the "Tantrasadbhāva-tantra" (eighth century), though other earlier tantras mention the visualization of Shakti in the central channel and the upward movement of prana or vital force (which is often associated with Kuṇḍalinī in later works). According to David Gordon White, this feminine spiritual force is also termed "bhogavati," which has a double meaning of "enjoyment" and "coiled" and signifies her strong connection to bliss and pleasure, both mundane physical pleasure and the bliss of spiritual liberation (moksha), which is the enjoyment of Shiva's creative activity and ultimate union with the Goddess.


title: Kundalini

text: In the influential Shakta tradition called Kaula, Kuṇḍalinī is seen as a "latent innate spiritual power", associated with the Goddess Kubjika (lit. "the crooked one"), who is the supreme Goddess (Paradevi). She is also pure bliss and power (Shakti), the source of all mantras, and resides in the six chakras along the central channel. In Shaiva Tantra, various practices like pranayama, bandhas, mantra recitation and tantric ritual were used in order to awaken this spiritual power and create a state of bliss and spiritual liberation.


title: Kundalini

text: According to Abhinavagupta, the great tantric scholar and master of the Kaula and Trika lineages, there are two main forms of Kuṇḍalinī, an upward moving Kuṇḍalinī ("urdhva") associated with expansion, and a downward moving Kuṇḍalinī ("adha") associated with contraction. According to the scholar of comparative religion Gavin Flood, Abhinavagupta links Kuṇḍalinī with "the power that brings into manifestation the body, breath, and experiences of pleasure and pain", with "the power of sexuality as the source of reproduction" and with:


title: Kundalini

text: Despite mostly being associated with Shaiva and Shakta traditions,the concept of Kundalini Shakti is not at all alien to Vaishnavism. Narada Pancharatra, A popular Vaishnava text gives a detailed, although somewhat different description of Chakras and Kundalini Shakti.


title: Kundalini

text: According to William F. Williams, Kuṇḍalinī is a type of religious experience within the Hindu tradition, within which it is held to be a kind of "cosmic energy" that accumulates at the base of the spine.


title: Kundalini

text: When awakened, Kuṇḍalinī is described as rising up from the muladhara chakra, through the central nadi (called "sushumna") inside or alongside the spine reaching the top of the head. The progress of Kuṇḍalinī through the different chakras is believed to achieve different levels of awakening and a mystical experience, until Kundalini finally reaches the top of the head, Sahasrara or crown chakra, producing an extremely profound transformation of consciousness.


title: Kundalini

text: Swami Sivananda Saraswati of the Divine Life Society stated in his book "Kundalini Yoga" that "Supersensual visions appear before the mental eye of the aspirant, new worlds with indescribable wonders and charms unfold themselves before the Yogi, planes after planes reveal their existence and grandeur to the practitioner and the Yogi gets divine knowledge, power and bliss, in increasing degrees, when Kuṇḍalinī passes through Chakra after Chakra, making them to bloom in all their glory..."


title: Kundalini

text: Yoga gurus consider that Kuṇḍalinī can be awakened by "shaktipat" (spiritual transmission by a Guru or teacher), or by spiritual practices such as yoga or meditation.


title: Kundalini

text: There are two broad approaches to Kuṇḍalinī awakening: active and passive. The "active approach" involves systematic physical exercises and techniques of concentration, visualization, pranayama (breath practice) and meditation under the guidance of a competent teacher. These techniques come from any of the main branches of yoga, and some forms of yoga, such as Kriya yoga, Kundalini yoga and which emphasize Kuṇḍalinī techniques.


title: Kundalini

text: The "passive approach" is instead a path of surrender where one lets go of all the impediments to the awakening rather than trying to actively awaken Kuṇḍalinī. A chief part of the passive approach is shaktipat where one individual's Kuṇḍalinī is awakened by another who already has the experience. Shaktipat only raises Kuṇḍalinī temporarily but gives the student an experience to use as a basis.


title: Kundalini

text: The twentieth century yogi and mystic Gopi Krishna, who helped to bring the concept of Kuṇḍalinī to the Western world, stated that


title: Kundalini

text: The American comparative religions scholar Joseph Campbell describes the concept of Kuṇḍalinī as "the figure of a coiled female serpent—a serpent goddess not of "gross" but "subtle" substance—which is to be thought of as residing in a torpid, slumbering state in a subtle center, the first of the seven, near the base of the spine: the aim of the yoga then being to rouse this serpent, lift her head, and bring her up a subtle nerve or channel of the spine to the so-called "thousand-petaled lotus" (Sahasrara) at the crown of the head...She, rising from the lowest to the highest lotus center will pass through and wake the five between, and with each waking, the psychology and personality of the practitioner will be altogether and fundamentally transformed."


title: Kundalini

text: According to the "Goraksasataka", or "Hundred Verses of Goraksa", hatha yoga practices such as the mudras mula bandha, uddiyana bandha, and jalandhara bandha, and the pranayama practice of kumbhaka can awaken Kundalini. Another hatha yoga text, the "Khecarīvidyā", states that khechari mudra enables one to raise Kundalini and access the stores of amrita in the head, which subsequently flood the body.


title: Kundalini

text: The spiritual teacher Meher Baba emphasized the need for a master when actively trying to awaken Kuṇḍalinī:


title: Kundalini

text: In his book, Building a Noble World, Shiv R. Jhawar describes his Shaktipat experience at Muktananda's public program at Lake Point Tower in Chicago on 16 September 1974 as follows:


title: Kundalini

text: According to Hindu tradition, in order to be able to integrate this spiritual energy, a period of careful purification and strengthening of the body and nervous system is usually required beforehand. Yoga and Tantra propose that Kuṇḍalinī can be awakened by a guru (teacher), but body and spirit must be prepared by yogic austerities, such as pranayama, or breath control, physical exercises, visualization, and chanting. The student is advised to follow the path in an open-hearted manner.


title: Kundalini

text: Traditionally, people visited ashrams in India to awaken their dormant kundalini energy with regular meditation, mantra chanting, spiritual studies and physical asana practice such as kundalini yoga.


title: Kundalini

text: David Eastman writing in Yoga Journal says that Kundalini can also awaken spontaneously for no obvious reason, or be triggered by intense personal experiences such as accidents, near death experiences, childbirth, emotional trauma, extreme mental stress, and so on. Some sources attribute spontaneous awakenings to the "grace of God", or possibly to spiritual practice in past lives. A spontaneous awakening in one who is unprepared or without the assistance of a good teacher can result in an experience which has been termed as "Kundalini crisis", "spiritual emergency" or "Kundalini syndrome". The symptoms are said to resemble those of Kundalini awakening but are experienced as unpleasant, overwhelming or out of control. Unpleasant side effects are also said to occur when the practitioner has not approached Kundalini with due respect and in a narrow egotistical manner. Kundalini has been described as a highly creative intelligence which dwarfs our own. Kundalini awakening, therefore, requires surrender; it is not an energy which can be manipulated by the ego.


title: Kundalini

text: Kuṇḍalinī is considered to occur in the chakra and nadis of the subtle body. Each chakra is said to contain special characteristics and with proper training, moving Kuṇḍalinī through these chakras can help express or open these characteristics.


title: Kundalini

text: Kuṇḍalinī is described as a sleeping, dormant potential force in the human organism. It is one of the components of an esoteric description of the "subtle body", which consists of nadis (energy channels), chakras (psychic centres), prana (subtle energy), and bindu (drops of essence).


title: Kundalini

text: Kuṇḍalinī is described as being coiled up at the base of the spine. The description of the location can vary slightly, from the rectum to the navel. Kuṇḍalinī is said to reside in the triangular sacrum bone in three and a half coils.


title: Kundalini

text: When Kuṇḍalinī Shakti is conceived as a goddess, then, when it rises to the head, it unites itself with the Supreme Being of (Lord Shiva). The aspirant then becomes engrossed in deep meditation and infinite bliss. Paramahansa Yogananda in his book "" states:


title: Kundalini

text: Krishnamacharya, often called the "father of modern yoga", described kuṇḍalinī differently. To him, Kuṇḍalinī is not an energy that rises: it is a blockage that prevents prāṇa vāyu (breath) from entering the suṣumnā and rising. This interpretation came partly from his own experience and partly from teachings of two sects of Vishnu-worshiping temple priests.


title: Kundalini

text: Sir John Woodroffe (1865–1936) – also known by his pseudonym Arthur Avalon – was a British Orientalist whose published works stimulated a far-reaching interest in Hindu philosophy and Yogic practices. While serving as a High Court Judge in Calcutta, he studied Sanskrit and Hindu Philosophy, particularly as it related to Hindu Tantra. He translated numerous original Sanskrit texts and lectured on Indian philosophy, Yoga and Tantra. His book, "The Serpent Power: The Secrets of Tantric and Shaktic Yoga" became a major source for many modern Western adaptations of Kundalini yoga practice. It presents an academically and philosophically sophisticated translation of, and commentary on, two key Eastern texts: "Shatchakranirūpana" (Description and Investigation into the Six Bodily Centers) written by Tantrik Pūrnānanda Svāmī (1526) and the "Paduka-Pancakā" from the Sanskrit of a commentary by Kālīcharana (Five-fold Footstool of the Guru). The Sanskrit term "Kundali Shakti" translates as "Serpent Power". Kundalini is thought to be an energy released within an individual using specific meditation techniques. It is represented symbolically as a serpent coiled at the base of the spine.


title: Kundalini

text: When Woodroffe later commented upon the reception of his work he clarified his objective, "All the world (I speak of course of those interested in such subjects) is beginning to speak of Kundalinî Shakti." He described his intention as follows: "We, who are foreigners, must place ourselves in the skin of the Hindu, and must look at their doctrine and ritual through their eyes and not our own."


title: Kundalini

text: Western awareness of Kuṇḍalinī was strengthened by the interest of Swiss psychiatrist and psychoanalyst Dr. Carl Jung (1875–1961). Jung's seminar on Kundalini yoga presented to the Psychological Club in Zurich in 1932 was widely regarded as a milestone in the psychological understanding of Eastern thought and of the symbolic transformations of inner experience. Kundalini yoga presented Jung with a model for the developmental phases of higher consciousness, and he interpreted its symbols in terms of the process of individuation, with sensitivity towards a new generation's interest in alternative religions and psychological exploration."


title: Kundalini

text: In the introduction to Jung's book "The Psychology of Kundalini Yoga", Sonu Shamdasani puts forth "The emergence of depth psychology was historically paralleled by the translation and widespread dissemination of the texts of yoga... for the depth psychologies sought to liberate themselves from the stultifying limitations of Western thought to develop maps of inner experience grounded in the transformative potential of therapeutic practices. A similar alignment of "theory" and "practice" seemed to be embodied in the yogic texts that moreover had developed independently of the bindings of Western thought. Further, the initiatory structure adopted by institutions of psychotherapy brought its social organization into proximity with that of yoga. Hence, an opportunity for a new form of comparative psychology opened up."


title: Kundalini

text: The American writer William Buhlman, began to conduct an international survey of out-of-body experiences in 1969 in order to gather information about symptoms: sounds, vibrations and other phenomena, that commonly occur at the time of the OBE event. His primary interest was to compare the findings with reports made by yogis such as Gopi Krishna who have referred to similar phenomena, such as the "vibrational state" as components of their kundalini-related spiritual experience. He explains:


title: Kundalini

text: Sri Aurobindo was the other great scholarly authority on Kuṇḍalinī, with a viewpoint parallel to that of Woodroffe but of a somewhat different slant - this according to Mary Scott, herself a latter-day scholar on Kuṇḍalinī and its physical basis, and a former member of the Theosophical Society.


title: Kundalini

text: Kundalini references may be found in a number of New Age presentations, and is a word that has been adopted by many new religious movements.


title: Kundalini

text: According to Carl Jung "... the concept of Kundalini has for us only one use, that is, to describe our own experiences with the unconscious ..." Jung used the Kundalini system symbolically as a means of understanding the dynamic movement between conscious and unconscious processes.


title: Kundalini

text: According to Shamdasani, Jung claimed that the symbolism of Kuṇḍalinī yoga suggested that the bizarre symptomatology that patients at times presented, actually resulted from the awakening of the Kuṇḍalinī. He argued that knowledge of such symbolism enabled much that would otherwise be seen as the meaningless by-products of a disease process to be understood as meaningful symbolic processes, and explicated the often peculiar physical localizations of symptoms.


title: Kundalini

text: The popularization of eastern spiritual practices has been associated with psychological problems in the west. Psychiatric literature notes that "since the influx of eastern spiritual practices and the rising popularity of meditation starting in the 1960s, many people have experienced a variety of psychological difficulties, either while engaged in intensive spiritual practice or spontaneously." Among the psychological difficulties associated with intensive spiritual practice we find "Kundalini awakening," "a complex physio-psychospiritual transformative process described in the yogic tradition." Researchers in the fields of Transpersonal psychology, and Near-death studies have described a complex pattern of sensory, motor, mental, and affective symptoms associated with the concept of Kundalini, sometimes called the Kundalini syndrome.


title: Kundalini

text: The differentiation between spiritual emergency associated with Kuṇḍalinī awakening may be viewed as an acute psychotic episode by psychiatrists who are not conversant with the culture. The biological changes of increased P300 amplitudes that occurs with certain yogic practices may lead to acute psychosis. Biological alterations by Yogic techniques may be used to warn people against such reactions.


title: Kundalini

text: Some modern experimental research seeks to establish links between Kuṇḍalinī practice and the ideas of Wilhelm Reich and his followers.


title: Reading F.C.

text: Reading Football Club ( ) is a professional football club based in Reading, Berkshire, England. The team play in the Championship, the second tier of the English football league system. The club is managed by Paul Ince.


title: Reading F.C.

text: Reading are nicknamed "The Royals", due to Reading's location in the Royal County of Berkshire, though they were previously known as "The Biscuitmen", due to the town's association with Huntley and Palmers. Established in 1871, the club is one of the oldest teams in England, but did not join The Football League until 1920, and first played in the top tier of English football league system in the 2006–07 season. The club competed in the 2012–13 Premier League season, having gained promotion at the end of the 2011–12 season after winning the Championship, but were relegated after just one season back in the top flight.


title: Reading F.C.

text: Reading won the 1987–88 Full Members' Cup and were one of only two Second Division clubs to lift the trophy. The club's best performance in the FA Cup was reaching the semi-finals which they achieved on two occasions: once in 1926-27 and again in 2014-15.


title: Reading F.C.

text: The club played at Elm Park for 102 years, from 1896 to 1998. In 1998, the club moved to the new Madejski Stadium, which is named after the club's former chairman Sir John Madejski. In 2021, the club announced that the ground would be known as the Select Car Leasing Stadium for the subsequent decade for sponsorship reasons.


title: Reading F.C.

text: The club holds the record for the number of successive league wins at the start of a season, with a total of 13 wins at the start of the 1985–86 Third Division campaign and also the record for the number of points gained in a professional league season with 106 points in the 2005–06 Football League Championship campaign. Reading then finished eighth in the 2006–07 Premier League, their first-ever season as a top-flight club.


title: Reading F.C.

text: Reading were formed on 25 December 1871, following a public meeting at the Bridge Street Rooms organised by Joseph Edward Sydenham, who would go on to be club secretary. The early matches were played at Reading Recreation Ground, and later the club held fixtures at Reading Cricket Ground, Coley Park and Caversham Cricket Ground. The switch to professionalism in 1895 resulted in the need for a bigger ground and, to this end, the club moved again, to the purpose-built Elm Park on 5 September 1896. In 1913, Reading had a successful tour of Italy, prompting the leading sports newspaper "Corriere della Sera" to write "without doubt, Reading FC are the finest foreign team seen in Italy".


title: Reading F.C.

text: Reading were elected to the Football League Third Division South of the Football League in 1920. Reading's best performance in the FA Cup came in 1926–27 when they lost to eventual winners Cardiff City at Wolverhampton in the semi-final, a placement the club would not match again until 2015, when they lost to holders Arsenal in the semi-final. Reading lost their place in Division Two in May 1931, and remained in Third Division South until the outbreak of World War II. The club won the Southern Section Cup, beating Bristol City in the two-legged final in 1938, and when taking part in the regional London War League and Cup competitions, gained another honour by beating Brentford in the London War Cup Final of 1941 by 3–2 at Stamford Bridge.


title: Reading F.C.

text: When League football resumed after the war, Reading quickly came to prominence once again. The club's record victory, 10–2 versus Crystal Palace, was recorded in September 1946, and Reading twice finished runners-up in the Third (South), in 1948–49 and 1951–52, but they were denied a return to Division Two as only the champions were promoted. The side's moment of cup glory came in 1988 when they won the Simod Cup, beating a number of top-flight sides en route to their Wembley win over Luton Town. Reading were promoted to the Second Division as champions in 1986 under the management of Ian Branfoot, but were relegated back to the Third Division in 1988.


title: Reading F.C.

text: The appointment of Mark McGhee as player-manager, shortly after the takeover by John Madejski, in 1991 saw Reading move forward. They were crowned champions of the new Division Two in 1994. Thirty-five-year-old striker Jimmy Quinn was put in charge of the first team alongside midfielder Mick Gooding and guided Reading to runners-up in the final Division One table – only to be denied automatic promotion because of the streamlining of the Premier League, from 22 teams to 20. In 1995, Reading had eased past Tranmere Rovers in the play-off semi-finals and looked to have booked their place in the Premier League only to lose 4-3 against Bolton Wanderers in the final having been 2-0 up and missed a penalty at half-time. Quinn and Gooding's contracts were not renewed two years later after Reading had slid into the bottom half of Division One. Their successor, Terry Bullivant, lasted less than a season before being sacked in March 1998. Reading were relegated back to Division Two at the end of the 1997-98 season.


title: Reading F.C.

text: The year 1998 also saw Reading move into the new 24,200 all-seater Madejski Stadium, named after chairman John Madejski. Tommy Burns had taken over from Terry Bullivant but lasted just 18 months before being replaced by Alan Pardew, who had previously been reserve team manager before being released. The club finished third in 2000–01 qualifying for the play-offs, losing 2–3 in the final against Walsall at the Millennium Stadium in Cardiff. Reading returned to Division One for 2002–03 after finishing runners-up in Division Two. The following season, they finished fourth in Division One and qualified for the play-offs, where they lost in the semi-final to Wolverhampton Wanderers. Alan Pardew moved to West Ham United the following October and was replaced by Steve Coppell.


title: Reading F.C.

text: Reading won the 2005–06 Championship with a league record 106 points, scoring 99 goals and losing only twice. They were promoted to English football's top division for the first time in their history. The 2006–07 season saw Reading make their first appearance in the top flight of English football. Reading defied pre-season predictions of relegation to finish the season in eighth place with 55 points. Reading turned down the chance to play in the UEFA Intertoto Cup. In the run up to their second season in the Premier League, Reading took part in the 2007 Peace Cup in South Korea. This second season was less successful, however, and Reading were relegated back to the Championship.


title: Reading F.C.

text: Reading started the 2008–09 season with a 15 match unbeaten home run. They finished fourth and qualify for the play-offs, where they lost to Burnley in the semi-final. Manager Steve Coppell resigned just hours after the game, replaced by Brendan Rodgers. Rodgers left the club by mutual consent on 16 December 2009 and Brian McDermott made caretaker manager the same day. In the 2010–11 FA Cup, Reading reached the quarter-final, where they lost 1–0 to Manchester City at Etihad Stadium, Reading eventually finished fifth in the Championship to qualify for the division's play-offs. After beating Cardiff City in the semi-finals, they lost 4–2 to Swansea City in the final at Wembley. In the 2011–12 season, a streak of good form in the second half of the season, ensured promotion to the Premier League on 17 April 2012 with 1–0 home win against Nottingham Forest.


title: Reading F.C.

text: McDermott led Reading to their first Premier League win of the 2012–13 season on 17 November 2012 at their 11th attempt, defeating Everton 2–1 at home. On 11 March 2013, however, he left his position at Reading. Nigel Adkins was then appointed as manager, though he was unable to save them from relegation after drawing Queens Park Rangers 0–0 on 28 April 2013 at Loftus Road.


title: Reading F.C.

text: The following season back in the Championship saw Reading make two high-profile signings in Wayne Bridge and Royston Drenthe in hope of an immediate return to the Premier League. Reading, however, missed out on the playoffs because of a last minute winner from Brighton & Hove Albion's Leonardo Ulloa, which meant the Seagulls made the playoffs at Reading's expense.


title: Reading F.C.

text: The summer before the 2014–15 season saw further arrivals of Jamie Mackie on loan, Oliver Norwood and the return of Simon Cox. The club was under a high threat of administration, causing departures of Sean Morrison and Adam Le Fondre and a Thai consortium taking over the club. A good start to Nigel Adkins' second season in charge was followed by a poor run of results that ended with his sacking after the 6–1 away defeat to Birmingham City with Steve Clarke taking over the next day in the hope of a promotion push. However, a lack of goals and some poor form in the league meant the club faced some fears of relegation to League One, but luckily safety was secured with few games to spare. Nonetheless, during that time, the club embarked on a successful FA Cup journey, reaching the semi-final where they were unlucky to lose 2–1 to Arsenal at Wembley. The following season saw the club bring in many players in the hopes of gaining promotion, however the club would finish in 17th.


title: Reading F.C.

text: In the summer leading up to the 2016–17 season the club announced the departure of Brian McDermott and eventually he was to be replaced by former Manchester United defender Jaap Stam. Under Stam, Reading achieved their highest finish since relegation back to the Championship by finishing third and reaching the play-offs, where they beat Fulham on aggregate before facing Huddersfield Town in the final at Wembley where they lost on penalties following 0–0 draw after extra time. However, the following season was a sharp contrast as the team were languished towards the bottom of the table for most of the season. On 21 March 2018, Stam resigned as manager after a nine-game winless run. Two days later, on 23 March 2018, Paul Clement was appointed as Reading's new manager, who finished the season in 20th place, avoiding relegation by three points.


title: Reading F.C.

text: The following season, Clement was sacked on 6 December 2018 after poor results left the club outside of the relegation zone only on goal difference. He was replaced by José Gomes on 22 December 2018, who steered the club away from relegation to finish 20th again. However, after a slow start to the 2019–20 season, Gomes was dismissed after less than a year in charge with the team in the relegation zone in October 2019. Sporting director Mark Bowen was promoted to the role as his replacement a week later, who lead the team to finish 14th before departing the club in August 2020.


title: Reading F.C.

text: Former Chicago Fire boss Veljko Paunović was appointed manager on 29 August 2020. The team got off to an excellent start to the 2020–21 season, winning seven of their first eight league games. However, the team's form faded after injuries to several key players and they eventually narrowly missed out of the playoffs, finishing seventh.


title: Reading F.C.

text: On 17 November 2021 it was confirmed Reading would be deducted 6 points due to breaching the EFL's profitability and sustainability rules.


title: Reading F.C.

text: Following a 3-2 away victory over Preston North End, Manager Veljko Paunović left his role by mutual consent, with Paul Ince being placed in interim charge of the club alongside Academy Manager Michael Gilkes. On 16 May 2022, Ince was announced as the team's permanent manager, with Mark Bowen also returning to the club in the role of Head of Football Operations.


title: Reading F.C.

text: The first crest to appear on a Reading kit was in 1953, it featured just the letter "R". There was no crest seen again until 1981 when there was a crest featuring three elm trees and the rivers Thames and Kennet; this only lasted two seasons. From 1987 to 1996 the crest used the new kit colours of yellow, sky blue, royal blue and white. A brief return to a design based on the 1981 crest was reintroduced for the 1996–97 and 1997–98 seasons. Commenting on the need for a new crest to coincide with the move to the Madejski Stadium, as well as moving into the new millennium, Sir John Madejski said: "I know some traditionalists will say we should keep the old badge but they should bear in mind the need to move forward." The current crest was first seen on the kits for the 1998–99 season. It is based on the club colours—blue and white—and includes a crown to represent the Royal County of Berkshire and the Maiwand Lion to represent Reading.


title: Reading F.C.

text: The club's home kit for the 2022–23 season saw University of Reading's Ed Hawkins' stripe design included on the sleeves with the stripes representing the average temperature for a single year since Reading's foundation to raise awareness for climate change, the shirt itself being made of recycled plastic bottles.


title: Reading F.C.

text: The club played at Reading Recreation Ground until 1878, before moving on to Reading Cricket Ground (1878–1882), Coley Park (1882–1889) and Caversham Cricket Ground (1889–1896).


title: Reading F.C.

text: In 1889, Reading were unable to continue playing at Coley Park as W B Monck (the local squire) no longer allowed football due to "rowdyism [by] the rougher elements". With club membership exceeding 300 by the time the club went professional in 1895, Reading required a proper ground. A meeting the following year determined that funding would be difficult. £20 was donated by J C Fidler, on the proviso that "no liquors were to be sold" on site. The rest of the cost was financed through donations by wealthy supporters, as well as one large individual donation. A former gravel pit in West Reading was identified as the site. The first game at Elm Park was held on 5 September 1896 between Reading and A Roston Bourke's XI. The visitors were a scratch team from Holloway College. £44 was taken on the gate, with an attendance of approximately 2,500.


title: Reading F.C.

text: In 1908, the club's annual general meeting proposed moving to a new ground near Reading railway station. A board meeting the following year decided that the move would not be possible, as "there was no chance of a move to the ground near to the GWR railway stations due to the actions of the Great Western Railway".


title: Reading F.C.

text: In 1994, the Taylor Report made an all-seater stadium compulsory in the top two divisions (the Premier League and the first division). Reading were champions of the second division in 1994, and were promoted to the first division. Reading became subject to the Taylor requirements, though converting Elm Park to an all-seater stadium would have been impractical. Instead, a location in Smallmead (to the south of the town) was identified as the site for a new stadium. The former council landfill site was bought for £1, with further conditions that the development of the stadium would include part-funding of the A33 relief road. Expansion of the club's home would also allow alternative commercial ventures (particularly leisure facilities) and shared use with other teams (such as rugby union clubs Richmond and London Irish). The last competitive match at Elm Park took place on 3 May 1998 against Norwich City, with Reading losing 1–0. Reading began the 1998–99 season at the Madejski Stadium. It was opened on 22 August 1998 when Luton Town were beaten 3–0. The stadium cost more than £50 million to build. For the first time in its history, Reading Football Club participated in the Premier League in the 2006–07 season. As a result of the sell-out crowds for their first few fixtures of the season, the club announced their intention, in October 2006, to make a planning application to extend the ground to between 37,000 and 38,000 seats. The application was made on 24 January 2007, proposing initially the extension of the East Stand with a further 6,000 seats (raising capacity to around 30,000) and subsequently extension of the North and South Stands to reach the full proposed capacity. On 24 May 2007, it was announced that planning permission had been granted to extend the stadium to a capacity of 36,900. Reading has made plans for a new training ground at Bearwood Golf Club to replace Hogwood park their current training facility.