Can the MIT license be applied to music?

Question: If not, are there any other good options for me to effectively allow use by everyone for almost any reason? I'd prefer to take a hands-off approach as opposed to attempting to place anything in the public domain, which seems to be quite painful and controversial.
Comment: @Graham, perhaps the fact that many jurisdictions don't seem to permit doing so - CC0 seeks to do something equivalent, but it deals explicitly with that problem.
Comment: What's painful and controversial about public domain? Surely that's the easiest solution of all, since anyone can do anything with the music and neither you nor anyone else has to supervise usage.
Comment: @TobySpeight That's not really true though. Some places may not actively let you relinquish rights, sure. But those are rights, not responsibilities. There is nowhere where you *have* to do anything as a creator. Someone using this work could have issues, of course, if you did a bait-and-switch on them. Then they'd have to follow whatever local rules for showing you intended it to be placed in the public domain, and that's the purpose of CC0. But you yourself - not at all, anywhere, ever.
Comment: Yes, agreed - just speculating on the claim "seems to be painful", which is probably misunderstanding by OP rather than something that's factually true.
Answer: Can it be applied? Yes. But it would seem unhelpful to make anybody using the music to repeat the contents of the MIT license which makes multiple references to "Software"; that is at best going to confuse anybody receiving the work.
Fortunately, there are licenses designed for more general creative works; the best known of these are the Creative Commons licenses. You likely want either the Creative Commons Attribution license (commonly known as CC-BY) if you want to keep the MIT-like behaviour of requiring attribution, or potentially the Creation Commons Public Domain Dedication (slightly less commonly known as CC0) if you're not concerned about receiving attribution.
Comment: @CemKalyoncu: Meh, nobody puts DRM on music these days anyway. Also, CC-BY only imposes DRM restrictions on the original, not on "Adapted Material" (derivative works).
Comment: CC-BY has DRM restrictions, Op might want to relax them if they want to be as close to MIT as possible.
Comment: I just wanted to point it out, a difference is a difference and most people has no idea about the DRM clause on CC-By.
Comment: What does "DRM restrictions" mean in this context (a license)?
Comment: @R..GitHubSTOPHELPINGICE Defined in Section 1(d) of the license ("Effective Technological Measures")
Comment: @PhilipKendall: AFAICT all CC-BY does is waive any right to legacy enforcement against removing DRM. It doesn't assert validity of DRM.
Comment: @R..GitHubSTOPHELPINGICE Philip probably meant to refer to section 2(a)(5)(B), which prohibits the application of Effective Technological Measures (as defined in 1(d)) to others' CC BY material. If Bob gets a CC BY work from Alice, Bob may not redistribute that work under a DRM-encumbered format. To answer your question directly about what DRM has to do with a license: in this case the license forbids the introduction of DRM onto the work by downstream distributors. In this way it differs from the X11/Expat license, etc.
Comment: @apsillers: Does it forbid encoding in a format with DRM, or just declare that the DRM can't be a ETM (i.e. that it can't enjoy the protection of law from someone RE'ing and stripping it)?
Comment: @R..GitHubSTOPHELPINGICE The language does indeed only apply to DRM mechanisms that satisfy the license's definition of an ETM, but to my layman reading, it seems that it outright forbids the application of ETMs, rather than attempts to nullify any legal protection they enjoy. As I read that section, it would still be illegal to crack ETM applied to CC BY work, but it is also true that the application of the ETM is a violation of license terms. Could you create DRM that operates exactly like some existing ETM but says essentially "it's legal to crack this" and avoid it being an ETM? Probably?
Comment: @apsillers: My interpretation would be that, if someone argues your cracking of the DRM is unlawful as a bypass of an ETM, they've admitted that they're infringing copyright of the work by having copied it in a manner they weren't licensed to do. As such, the reasonable thing for them to do would be to declare that the DRM isn't an ETM in this context, just an artifact of the format, and that you're welcome to remove it.
Answer: You certainly could use the MIT license for a piece of music, but it's probably not a good idea.  Software licenses are very different than licenses for so-called "cultural works" (things like art, music, or literature).  In the early days of free software, these differences caused problems for several software projects who used licenses that were designed for cultural works and did not provide the same freedoms/protections when applied to software.  I'm not aware of any specific cases the other way around, but you'd be much better off selecting a license that was designed specifically for cultural works.
The MIT license includes a long section that talks about how the software has no warranty, etc.  That entire paragraph doesn't really mean anything in the context of a piece of music and would simply be confusing.  It's also a significant portion of the license text.  If you removed that paragraph you could also remove the clause that requires the disclaimer to be reproduced in any copies of the work.  By the time you removed all the irrelevant content, you'd end up with a very different license.
You have a number of available licenses that you can use that are designed for cultural works - not software - and should give you better protection with fewer hidden gotchas.  Select one based on your specific needs.
GPL-style licenses (derivative works must use a similar license):

Free Art License - Analagous to the GPL, but designed for artistic works.
CC BY-SA - Requires attribution and derivative works must use the same license.

MIT-style licenses:

CC BY - Requires attribution only.
MirOS License - Variation of the MIT license designed to be more broadly applicable (refers to generic "works", not programs). Specifically worded to meet certain European legal requirements but should also work elsewhere.
WTFPL - Absurdly simple license.  Grants the most rights in the fewest possible words.
Unnamed GNU license for support files - This is what the GNU project uses for small non-code files (READMEs, etc). It's two sentences, and essentially what you'd get if you removed all the software-specific stuff from the MIT license. Unlike the other GNU licenses, this one is not viral.

Free use, but no derivative works:

GNU Verbatim Copying License - Extremely simple license that allows free use and copying, but does not permit changes.  If you roll your own license, this is a good starting point.

Public domain equivalents (grants all permissions, while also forfeiting your own rights):

CC0 - Releases the work into the public domain in locales where such a thing is possible. In other areas, it provides the legalese necessary to have the same effect.  Some locales won't let you give up certain rights, but CC0 ensures that won't limit what others can do with the work.
The Unlicense - Same concept as CC0 but with simpler wording.  Specifically references software, but change the word "software" to "work" and the first three paragraphs should be all you need.

If you decide to use one of the Creative Commons licenses, make sure you use one that has the "approved for free cultural works" badge.
For cultural works, I recommend one of the MIT-style licenses (the unnamed GNU license in particular) over a public domain style license.  They give users the same permissions, but you avoid giving up any of your own rights as the creator.  Those rights might be important later if (for instance) someone wants to publish your work as part of a compilation and needs an explicit authorization from the copyright owner.  They also help ensure that you are properly credited as the creator, which is an important tradition in the music world.
Comment: Might help to note that The Unlicense is illegal in some countries, limiting audience reach.
Comment: @aggregate1166877 Illegal as in "using it is a criminal offense", or as in "doesn't provide all the protections that you need"?
Comment: Illegal as in "cannot be applied" in some countries. See: https://softwareengineering.stackexchange.com/questions/147111/what-is-wrong-with-the-unlicense
Comment: But to give a real example: in countries like Germany it is explicitly illegal to relinquish all rights, which is exactly what the Unlicense attempts to do.
Answer: The MIT License is generally used to absolve the creator of any potential liability, offering the software/product for use "as-is". While music (esp vocals/lyrics) can be viewed as controversial or harmful by some listeners, depending on the country & its laws, artists/creators may be protected from prosecution (First Amendment protections, in a US context).
However, just like various US cases where music creators were challenged under obscenity laws, separate from any intellectual-property claims, I don't think any license you use actually protects you from listeners' potential claims of harm down the line.
The best you can reasonably do, is to choose a license that restricts type/scope of use (Creative Commons has several, here's their license chooser), and add your own additional clause requesting that users ask you for permission for any uses beyond that. Such an approach doesn't free you from liability, but at least gives you more control over how your music will be used, so you can hopefully avoid any problematic applications.
Answer: You can as well make your music royalty free while still retaining all copyrights and rights to be known as the author. It would not be impossible to have there be exception if you want. If you are Ok with your music being used on YouTube but don't want it used in a porno for instance.


Number of possible unique patterns of $5$ points on an $8\times 8$ grid.

Question: I'm after a specific answer and workings/formula for the number of possible unique patterns that $5$ points can have on an $8\times 8$ grid. The pattern must be unique and not match another pattern when it's rotated or mirrored. Can the workings be explained in laymans terms? Thanks
Comment: Are there $64$ or $81$ possible locations for the points? (In other words, do I place the pieces like in chess or like in go?)
Comment: As well as that, can more than one point occupy a grid space?
Comment: Hey Parcly, its 64 like chess. only 1 point per slot. 64 available positions
Answer: We solve the case of the points going into the slots between the grid,
so there are  $64$ slots. We put  at most one point into  one slot. We
use  the Polya  Enumeration Theorem  (PET), which  requires the  cycle
index of the action of the symmetries on the slots. Supposing the grid
is $n\times  n$ with  $n$ even  we get for  the rotations,  first, the
identity:
$$a_1^{n^2}.$$
Next, two rotations by $90$ degrees and $270$ degrees:
$$2 a_4^{n^2/4}.$$
The rotation by $180$ degrees:
$$a_2^{n^2/2}.$$
For reflections there is the horizontal and the vertical reflection:
$$2 a_2^{n^2/2}$$
and the reflection in the two diagonals:
$$2 a_1^n a_2^{(n^2-n)/2}.$$
We get the cycle index
$$Z(G) = \frac{1}{8}
\left(a_1^{n^2} + 2 a_4^{n^2/4} + a_2^{n^2/2}
+ 2 a_2^{n^2/2} + 2 a_1^n a_2^{(n^2-n)/2}\right)$$
or
$$\bbox[5px,border:2px solid #00A000]{Z(G) = \frac{1}{8}
\left(a_1^{n^2} + 2 a_4^{n^2/4}
+ 3 a_2^{n^2/2} + 2 a_1^n a_2^{(n^2-n)/2}\right).}$$
For an odd number of points call is $m$ we thus have
$$[z^m] Z(G; 1+z) \\=
[z^m] \frac{1}{8}
\left((1+z)^{n^2} + 2 (1+z^4)^{n^2/4}
+ 3 (1+z^2)^{n^2/2} + 2 (1+z)^n (1+z^2)^{(n^2-n)/2}\right)
\\ = [z^m] \frac{1}{8}
\left((1+z)^{n^2} + 2 (1+z)^n (1+z^2)^{(n^2-n)/2}\right).$$
This is
$$\bbox[5px,border:2px solid #00A000]{\frac{1}{8} {n^2\choose m}
+ \frac{1}{4} \sum_{k=0}^{n/2-1}
{n\choose 2k+1} {(n^2-n)/2\choose (m-2k-1)/2}}$$
where $n$ is even and $m$ is odd.
 We get for $n=8$ and $m=5$ the answer
$$\bbox[5px,border:2px solid #00A000]{954226.}$$
Comment: Awesome thanks Marko!
Comment: Hey Marko, sorry but 1 adjustment to add a layer of complexity, what if in 2 opposing corners 2 of the points are allocated so the other 3 are left to occupy the remaining 62 positions. is it possible to work out the unique arrangements of those remaining 3 points?
Comment: These are diagonally opposed corners?


Similar LMs, very different results. Possible causes?

Question: First I ran the following model:
$$y = \beta_1 x_1 + \beta_2 x_2 + ...$$
And I tested (t-test) if $\beta_1>0$ and $\beta_2>0$, which is true for both.
Then I split $x_1$ in two, such that $x_{1a}+x_{1b}=x_1$:
$$y = \beta_{1a} x_{1a} +  \beta_{1b} x_{1b} + \beta_{2} x_{2} + ...$$
Then I ran the t-tests to check which coefficients were positive. Only $\beta_{1b}$ was.
What are the possible reasons for $\beta_2$ no longer being positive after splitting the first regressor in two? I tried to run different models, for instance, deleting $x_{1a}$ and $x_{1b}$ from the model or deleting only one of them, but still $\beta_2$ isn't positive. How can it be that it only works in the first model? Any insights are appreciated. Please note that there are many other regressors in the model, so that could be the problem.
I should also add that I'm simplifying the problem. I'm fitting this model to several data sets, then checking if the mean $\beta_2$ is positive. I don't know if that makes any difference.
And to give it even more context, there are two sets of points I'm trying to predict, set 1 and set 2, which importantly overlap somewhat. $x_1$ tries to predict both set 1 and set 2, while $x_2$ tries to predict only set 2 (but this isn't clear cut because as I mentioned the sets overlap). The issue here is that set 2 is easy to predict. Set 1 is where it's at. So when I got the first results, they suggest that $x_2$ explains set 1, but we don't know if $\beta_1>0$ because $x_1$ is a good predictor set 1 or  set 2 or both. It should be a good predictor of set 2, so it's possible that it doesn't predict set 1 at all. So I split $x_1$ into two, with $x_{1a}$ trying to predict set 1 and $x_{1b}$ trying to predict set 2. So $\beta_{1b}$ was very highly statistically significant, which surprises no one as set 2 is easy to model.
The surprising part is that neither $\beta_{1a}>0$ nor $\beta_2>0$ in the second model! It's like the first model can explain set 1 but the second cannot. But how can that be true? The second model has the same information as the first but more terms. If anything, it overfits the data. It cannot possibly fit the data set any worse. It cannot possibly fit the set 1 points any worse! And yet it seems unable to say anything about set 1. It's important for my research to know why. Does $x_2$ suck as a regressor? Or is there a trivial (unrelated to $x_1$) explanation for its failure within the second model?
Answer: The answer is that $x_{1a}$ and $x_2$ are negatively correlated and not correlated at all with $y$. Because $x_{1b}$ is positively correlated with $y$, when I sum $x_{1a} + x_{1b}$, the coefficient for the sum ends up being positive, but also for $x_2$, because $\beta_2 x_2$ partially cancels out $\beta_1 x_{1a}$.


Why small planets are not attracted by larger planets due to gravitational force?

Question: Gravitational force means"the force experienced between two heavenly bodies".A body falls on any planet due to gravitational force.But smaller planets are not attracted by larger planets or stars(sun) due to this force. What is the reason for this?
Comment: Possible duplicate of [Why doesn't the Moon fall upon Earth?](http://physics.stackexchange.com/q/9049/)
Comment: This is a new question, and has a simple answer :  the earth and the sun and all the planets  move about the center of mass of the solar system. Everything moves!.
Comment: Please do not make edits that change your question entirely, especially after answers have been given, but [ask a new question](http://physics.stackexchange.com/questions/ask) instead
Comment: Duplicate #2: http://physics.stackexchange.com/q/312492/
Comment: Hi DARYL JOSEPH G, Welcome to Phys.SE. Echoing what @ACuriousMind said I roll back the question to v2. Oh, he already did it.
Answer: Tie a weight to a string.
Pull on the string. The weight hits you. You are doing to the weight what gravity does.
Now swing the weight in a circle. You are still pulling the weight toward you, doing what gravity does.
Answer: Newton was the first to connect "falling motion" and the motion of "heavenly bodies". He said these two motions had the same origin: the gravitational force. But to explain how the Earth and other heavenly bodies do not fall, while the apple does, he needed to define how motion works and what quantities are involved. In what are now known as Newton's laws (because they seem to hold for all bodies) he said that bodies can and will move in a straight line with constant velocity if no forces are present, and the effect of forces acting simultaneously is such as if only  one force was acting, equal to their sum. Whatever the force, its effect is a change in the motion of the body, possibly in both direction and magnitude. Finally he stated that if a body exerts a force upon another, it will in turn be subjected to an equal and opposite force. These elements, expressed mathematically, allow to describe exactly the motions of the falling apple and the heavenly bodies under their respective conditions.
But to answer your question maybe math is not necessary if we think of similar examples. While a force changes motion, it cannot avoid the inertia of the body, its tendency to "go as it was going". So a force applied sideways to the direction of motion will make it turn (slower or faster depending on how strong the force is compared to how fast the initial motion was). But by the time the turn happens, the body has moved forward a bit. Similarly when turning on a car, the friction of the street on the side of the wheel pushes it sideways, but does not make it turn in place, unless the force is strong enough. In such a way, the Earth is moving away from the Sun  whose force acts sideways to the motion, but it can only make it turn a bit every time the Earth moves forward. Unlike the car, the Earth is moving in a frictionless space and loses almost no energy in its motion, so unlike the car, its forward motion is sustained for extremely long time.
Answer: As Earth has tangential velocity it will not be pulled into the Sun, but will go into orbit. If it had little or no tangential velocity then it would be pulled into the Sun.


Is there a better criteria for meaninglessness than what the positivists came up with?

Question: I think the positivists came up with the idea that a statement is meaningless if it cannot be proven. But obviously this isn't true: there are a lot of scientific theories that cannot be proven yet, and some theories that may never be able to be proven, so this cannot be true. So is there a better criteria someone came up with or not? Because the claim that a statement is meaningless if it cannot be proven cannot be proven either.
Comment: This is not the criterion positivists came up with, their criterion of meaningfulness was contribution to making predictions (and even what they classified as "meaningless" could still have meaning in a more broad sense, on their conception, expressing emotions, for example). And no, general meaning turned out to be far too versatile and elusive for any kind of tractable criteria. Even the more restricted problem of [demarcating scientific from non-scientific statements](https://plato.stanford.edu/entries/pseudo-science/#AltDemCri) remains without a non-controversial solution.
Comment: Your definition of the terms sentence, statement & proposition are likely wrong or poorly defined which is why you think the way you do here. A statement does not have to be either true or false first off. Perhaps you heard that & belived it from math. This is false. Next you claimed something without proof is meaningless which again you are taking from math which is wrong. Axioms & definituons would all be meaningless under your thinking. Meaningless as defined correctly means a statement that ascribes a quality impossible to have would fail to Express something true or false..
Comment: You might be interested to read this discussion 'According to the major theories of concepts, where do meanings come from?'  https://philosophy.stackexchange.com/questions/77261/according-to-the-major-theories-of-concepts-where-do-meanings-come-from/77284#77284
Comment: Also, a ground-up version of 'true' https://philosophy.stackexchange.com/questions/81655/why-is-a-measured-true-value-true/81664#81664
Comment: what you are referring to is the popular notion of 'theory' and not the scientific definition of 'theory'. Scientific hypotheses are unproven, scientific theories are proven.
Answer: First of all logical positivists criterion for meaningfulness of a propositional statement or hypothesis is called verification principle, thus it's all about empirical verifiability not any form of provability or derivability wished in a complete strong deductive system since provability can be achieved without empirical verification like in logic and math and is regarded as mere semantic language convention (a tool) at best if not meaningless tautology at worst per positivists.

Verificationism, also known as the verification principle or the verifiability criterion of meaning, is the philosophical doctrine which maintains that only statements that are empirically verifiable (i.e. verifiable through the senses) are cognitively meaningful, or else they are truths of logic (tautologies)

As you intuited, this principle itself cannot be empirically verified since many scientific theories and hypotheses cannot be conclusively verified exhaustively, so later Carnap advocated confirmation instead of verification.

Logical positivists within the Vienna Circle recognized quickly that the verifiability criterion was too stringent. Notably, all universal generalizations are empirically unverifiable, such that, under verificationism, vast domains of science and reason, such as scientific hypothesis, would be rendered meaningless... Hahn argued that the verifiability criterion should accede to less-than-conclusive verifiability...

In 1936, Carnap sought a switch from verification to confirmation. Carnap's confirmability criterion (confirmationism) would not require conclusive verification (thus accommodating for universal generalizations) but allow for partial testability to establish "degrees of confirmation" on a probabilistic basis. Carnap never succeeded in formalizing his thesis despite employing abundant logical and mathematical tools for this purpose.

Later Popper's falsificationsim inherited the logical empiricism nature while changed verification or confirmation to his famous falsification.

Karl Popper's The Logic of Scientific Discovery proposed falsificationism as a criterion under which scientific hypothesis would be tenable. Falsificationism would allow hypotheses expressed as universal generalizations, such as "all swans are white", to be provisionally true until falsified by evidence, in contrast to verificationism under which they would be disqualified immediately as meaningless.

Below is the the summary judgement of falsification within philosophy and science circles from the same reference.

Although Karl Popper's falsificationism has been widely criticized by philosophers, Popper is often praised by many scientists. Verificationists, in contrast, have been likened to economists of the 19th century who took circuitous, protracted measures to refuse refutation of their preconceived principles.
Comment: What you describe has already been attributed to all sciences before logical positivism.  Why would this definition be created by logical positivism when all scientific evidence prior to this required empirical evidence or aka the verification principle.  The word proof alone implies there is SOME VERIFICATION involved. Show me a proof without some kind of verification   Just to be clear what verification MEANS is that a human must rely on at least one of the famous five senses: sight, smell, touch, taste & listening.  There is no science without verification !!!
Comment: @Logikal Thx for your critique. Your common intuition about science makes sense and is similar in spirit as the summary above judging positivists as circuitous, protracted. However, the stake here of verificationism is related to philosophy in general, not science. Positivists holding a Quine-like naturalistic epistemology wanted philosophy subsumed into science with same verification criterion of science (your point above). This would render many traditional metaphysical questions like "Do all existences precede essences (existentialism)?" meaningless since no way to verify such proposition..
Comment: I think the view represented Is not complete or accurate. Philosophers know that science is NOT Philosophy & Philosophy is not science. The notion here is about the definition of what is a STATEMENT & how all statements cannot be PROPOSITIONS.   Many people today have the poor definition of a proposition is a STATEMENT & these same people hold all STATEMENTS must be either true or false. Hence propositions must be true or false. Meaningful statements can be verified.  By meaningful they mean literally & physical in reality. Thus we cannot speak about unicorns as they are not literal.
Comment: The terminology is what is being attacked not whether the verification principle is valid in Philosophy. All statements are NOT propositions is what this amounts to. We also have multiple classifications of  STATEMENTS: meaningful & meaningless. Positivists hold all literally meaningful statements are those that Express propositions-- not the other kinds of statements. What is a statement then? A statement can be letters, a word, a signal, an action that communicates something to another human being. It doesn't HAVE TO BE true or false. Thus all statements are not propositions & vice versa.
Comment: @Logikal Of course strictly speaking propositions are just truth-valued formulas requiring interpretation of appropriate statements in a certain natural or formal language for its semantics, and there's confusion in many places. The OP title is mainly concerned about criterion for meaningfulness from positivists POV and beyond, so my answer just addresses this aspect. You're welcome to answer OP from your POV of difference of statements and propositions in general...
Answer: If you want to know whether a statement is likely to be meaningful, look at the process that generated the statement.  Look at the selection pressure that this process imposes on statements to filter out the "wrong" ones and keep the "right" ones.  Is it strong selection pressure, or weak?  Is it systematic and impersonal, or informal and social?  Is it based in fact or opinion?  Do influential parties in the process have a strong reason to lie or exaggerate, and how strongly does the process punish them for doing so?
If the process involves systematic, impersonal, formal, fact-based strong selection of ideas, then statements coming out of that process are more trustworthy.  Mathematics, hard sciences, engineering, chess, and sports are areas where if you fail, you fail objectively.  Therefore, statements in these fields tend to be more grounded.
If the process involves informal, social, opinion-based, weak selection of ideas, then statements coming out of that process are less trustworthy, and may not be meaningful.  Statements made in advertising, political lobbying, entertainment, fashion, and alternative medicine tend to succeed or fail based on whether people subjectively like them, while being fairly detached from hard evidence.
Ultimately, a statement is meaningful if it makes some significant difference to us whether it's true or false, beyond just how we feel about the statement.

Does it propose some state of affairs in the physical universe?  Then it is meaningful, although sometimes it may be hard to verify, and just because it is meaningful does not make it true.
Does it describe some property of a formal, rigorous system, such as mathematics?  Then it is meaningful.
Can we see how we might translate it into one of the above?  Then maybe it is meaningful.
Is it so vague that we can't even sketch out how it relates to a physical state of affairs or a formal system?  Then perhaps it is not meaningful, or needs more development to become meaningful.

We can ask, of a statement P, "What other propositions would hold as a result of P being true, and what would be the impact of those other propositions being true?"
However, in philosophy we may deal with "precursors" to meaning - statements whose meaning we are still uncertain of.  And just because we might not have pinned down the precise meaning yet, does not mean there is none.  "X is moral" or "X is conscious" come to mind in this category.
Answer: I start from the assumption that it is statements and words that can be said to be meaningful or meaningless.
A statement or a word will be meaningful for anyone who has a meaning in mind to associate to it. Thus, meaningfulness is a personal and subjective fact. Different persons will inevitably disagree as to whether particular statements are meaningful or not. Most conspicuously, the Chinese tend to be able to make sense of statements in Chinese only while the Germans tend to be able to make sense of statements in German only.
There is an interesting distinction between statements and words in this respect. We learn the words with our mother tongue and even when learning a foreign language. Mostly, people have zero problem associating a meaning to most words in the language they know.
While meaning often involves some interaction of the subject with the particular concrete objects referred to by words, this is apparently not a necessary condition at least for words best described as abstract. The concept of God for example shows that we are able to arrive at a meaning through abstraction. Essentially, the concept of God is arrived at as a logical conjunction of predicates whose meaning originally came from concrete objects. In this instance, God is essentially abstracted from humans themselves and understood as a sort of super-human.
The concept of God is also a social construct, but it is clear that individuals can work out their own private menagerie of quirky concepts they may or may not then publicise for the benefit of others, and we can think of philosophers like Hegel and Kant in this respect.
Statements are clearly different from words in terms of their meaning. A meaningful statement first requires that the words it is made of be themselves meaningful as per the above. But, this is not sufficient. It is also necessary that there be no contradiction between the different words involved. Thus, statements need to be logical.
This leads to distinguish between two levels of meaningfulness. First, what I would call "literal meaningfulness", which is obtained once all the words in the statement are meaningful. And then what I would call "semantic meaningfulness" when there is no contradiction between the words involved in the statement. Both levels of meaningfulness are necessary to achieve statement meaningfulness.
Thus, there is no hard connection between meaningfulness and the reality of the world, but there is nonetheless a loose connection with our experience of the world, both as individuals and as a collective. Individuals can make sense of their own personal experience, but the connection to a linguistic community will dramatically increase the number and range of the abstraction we can understand as individuals.
Logical positivism should be seen as essentially an ideological moment in philosophy, a logical absurdity, historically dated, at a time where the conflict between idealism and materialism climaxed.
Common sense is good enough to specify what meaningfulness means to most people. And only common sense is good enough, by logical necessity. And it works. Mankind has survived thousands of years on this basis. Logical positivism should have been debunked as illogical from the start.
This also shows that people can make statements which are illogical, including intellectuals. The reason is that our philosophical views can be quite sprawling and complex, to the point where the absurdity of them is lost to us. We continue to make claims which are absurd until it is pointed out to us that they are absurd. We can contradict ourselves. This implies that our theories are collections of statements, and that at any one time we can only entertain some of these statements, which leaves room for theories or views involving statements that will be individually meaningful but collectively meaningless.


Is 2h 20min layover in Alicante airport (Spain) enough?

Question: I am coming from non-EU/non-Schengen and going to Helsinki, Finland. The layover in Alicante airport is 2h 20min and the flight is self-transfer (Vueling, then Norwegian or Finnair).
Do I have enough time to check out my luggage and check it in to the next flight?
Comment: Could be tight, especially if your inbound flight is delayed. From https://www.aeropuertoalicante-elche.com/eng/checkin-alicante.htm *"The passenger should be at the check-in counter at least with 3 hours prior the departure scheduled time for No Schengen flights and 2 hours for Schengen and domestic flights."* When are you travelling?
Comment: When it comes to flights, I like to have ample margins when possible. I don't mind spending a little more time at the airport, I would definitely dislike missing the following flight. Why play with fire?
Comment: I understand. I'm travelling on the 1st of September.
Answer: The check-in deadline for both Norwegian and Finnair is 45 minutes. So that means, if your incoming flight is on time, you actually only have 1h35 to:

deplane
get to immigration, queue and get through
reclaim your bags
go through customs
get to the departures area and the check-in area for your outgoing flight
queue and check-in there

There are most likely also some COVID-related checks somewhere, though I wouldn't know where.
Now, given that a majority of gates at that airport are not sky bridges, that is likely to mean a bus from the aircraft to the terminal, which easily takes a good 15-20 minutes in most airports.
All in all, it is possible you may be able to do it with time to spare if everything goes smoothly. Whether you will actually do it is a matter for the stars. Given the risk associated (missing your flight most likely means having to buy a new ticket at last minute prices on the next available flight, possibly the next day or even later), I would definitely not recommend it, especially these days.
Comment: @dezkev I just hate people who (try to) jump queues because they can't plan ahead and have enough margin. Jump the queue because your flight is delayed, not because you originally didn't plan enough time.
Comment: The OP does't mention whether they're an EU citizen or not, which can be a significant difference, in terms of probability of immigration issues or additional checks.
In a similar situation, on a non-EU to EU flight to Madrid, I almost lost the following flight because the person who was traveling with me was non-EU. I breezed through immigration, she was stopped for additional questioning. We made it, but barely.
Comment: Request people before you in the immigration queue to allow you to jump the queue as you have a connecting flight in an hour or so.
Comment: Most departures that don't use a skybridge have the passengers walk to the aircraft from the terminal. The remote stands are actually pretty close to the terminal building.
Comment: @jcaron perhaps not always, but often, when your flight is delayed and it's the airline's fault, their personnel escorts you and helps expedite your luggage and your transfer to the next gate. So, it is likely that people trying to jump queues with no escort didn't plan enough time.
Answer: No one knows.
If things go well, then yes, if there are any issues (delayed flight, Corona test, baggage slow, long line at immigration, extra doc checks, long check in lines), then no.
For a self transfer you carry the full risk of missing the second flight. Personally I do not do self transfers with less than 4 hours and sometimes more if there are extra risk factors.
I would not book this.
Answer: Alicante Airport is not large, with only one terminal, and almost all flights end on a finger. Without any setback, it is more than enough time.
Comment: Hoe often have you done a non-Schengen to Schengen tranfer on that airport and how often on two separate tickets?
Comment: Walking from one end of the departure lounge to the other can take quite a while and there are no passenger conveyors. It's not a very large airport, but it's not set up well for transfers.
Comment: @jwenting Been through Alicante a number of times myself. Bagage handling can be VERY slow there as well. Having to wait for 50-60 minutes for your bags to show up on the belt. 2.20 is silly risky for Alicante.
Comment: @Tonny it can be, I've been there quite a few times myself and waiting times for baggage can indeed vary wildly.


How to set iPod tracks to remember playback position

Question: I've tried using Banshee, Amarok, and Rhythmbox, and so far I've been unable to set the "Remember Playback Position" property of some files.  In iTunes this was done through the "Get Info" menu but I don't see any way to do this in the aforementioned programs.  How can I do this with Ubuntu?
Answer: You probably will have to use iTunes to use this specific feature for an iPod. The feature isnt available through the apps you have mentioned.
This isnt the same as setting "Remember Playback Position" for every individual track as can be done via iTunes, but the following SU link discusses creating a python script to remember a specific point in a playlist: https://superuser.com/questions/249565/music-player-for-linux-which-remembers-the-playback-position


How to pronounce a name you see for the first time?

Question: Could you please tell me how to pronounce a name (interpreted from other languages) for the first time you see it? In English I find it difficult to do so because of the flexible pronunciation of letters and different stress on syllables. For example, like the name Powhatan (I see it in a story).
Comment: FWIW, [Wikipedia](https://en.wikipedia.org/wiki/Powhatan) gives two options: /paʊhəˈtæn/ or /paʊˈhætən/.
Comment: Even native speakers don't always know, unless the writer provides a pronunciation guide.
Answer: Ask a person how their name is pronounced if you're not sure.
Simply put, names are one of those areas where words are imported into English from many different languages and are often simply transliterated, and may not follow standard English pronunciation rules. Additionally, there are some individuals who give their children "unique" names with unpredictable pronunciations. As such, if you see a person's name and you're not sure how to pronounce it, the best thing to do is simply to ask how it's pronounced.
If you're reading a book and you're not sure how a character's name is pronounced, just use standard English pronunciation in your head, but be aware that you might be wrong, especially if it's a "foreign" name.
Comment: Agreed. English has no *rules/ guidelines* for pronouncing names. Names are pronounced the way the person does.


Packet transfer from one host to another

Question:
I was reading about how a packet is send from one host to another. I am confused about entries that will be made in layer-3 switch routing table. Does it contain the entries for layer two switches or does it contain the entries for all the hosts (A,B,C,D ... etc).
Answer: A routing table will have entries for the directly connected networks, any static routes you have configured, and any routes learned through routing protocols that you may be running to exchange routes with other routers.
The routing table entries for each network will include the interface to which traffic destined for that network should be sent.
Based on you drawing: You could have three routes for the directly connected networks. You probably have a statically configured default route for the Internet, or you may be running BGP with the ISP router to which your layer-3 switch connects, in which case, you may have other routes learned from the ISP router.
Comment: Thanks, for the reply. But i'm still confused about Layer-3 switch routing table. Layer-3 switch routing has details (Network id, netmask, next hop, Interface) for an entry. But layer two switch has no IP address. And Host A,B,C are in one subnet and hosts D,E,F,G are in other subnet. So i'm also confused about who is managing networks layer-2 switch or layer-3 switch.
Comment: Layer-2 switches are only concerned with layer-2, and they know nothing about layer-3 networks. A layer-3 switch is a layer-2 switch, but it has a routing module. Layer-3 and layer-2 really know nothing about the other. There are many layer-2 protocols which can each carry a variety of layer-3 protocols. The layer-2 protocol doesn't really care what layer-3 protocol it encapsulates, nor does the layer-3 protocol care in which layer-2 protocol it is carried. Layer-2 simply knows nothing about routes, it delivers frames based on the layer-2 address on a flat layer-2 network.
Answer: Layer2 won't understand ip address , layer2 switch will only forward traffic on basis of  mac-addres table
Let have example
Packet forwarding to  host A from layer3 switch
Once the packet reaches layer3 switch as host A as destination  , layer3 devices process this packet by varyfying routing table , in routing table it found that this network was directly connected networks .hence packet is forwarded on interfàce where network is connected so in this case packet is forwarded to access-switch layer2 Switch1 from this switch frame is forwarded to correct destionation based on mac -address table present in Switch1.


Creating a emission plane and hiding it in Blender 2.81

Question: How do I create emission material and then hide the plane that emits the light in Blender 2.81?
Comment: Are you trying to get the same effect as an *Area Light?* You can press Shift+A, *Light* > *Area* to add one of those.
Answer: Use the Light Path node to make the material appearance different from its influence.
From Add > Input > Light Path use the Is Camera socket to mix between your Emission Shader and a Transparent Shader.


How do i find the path of a linux program?

Question: i need to find the complete path of a given Linux executeable?
How can i do this?
For example the real path of cat is /bin/cat
Answer: Use which or locate:
$ which cat
/bin/cat

Answer: You can use the which command:
$ which ifconfig
/sbin/ifconfig

Answer: which program or whereis program
$  whatis which
which                (1)  - shows the full path of (shell) commands

$  whatis whereis
whereis              (1)  - locate the binary, source, and manual page files for a command


Why no right to a jury trial in Espionage Act trials?

Question: Why are defendants in trials for alleged criminal violations of the 1917 US Espionage Act, -- as, say, Julian Assange would be if extradited to the US -- not afforded the same right to an open and public jury trial that all other defendants in criminal cases are allowed?  Is this patent violation of the defendant's Sixth Amendment right to a jury trial written into the Espionage Act itself,or is it justified by arguments from other legal precedents?
Comment: What makes you believe there is no such right?  As far as I know, this right exists and applies to the Espionage Act just as to all other crimes.  For instance, I believe the [Rosenbergs](https://en.wikipedia.org/wiki/Julius_and_Ethel_Rosenberg) [received a jury trial](https://famous-trials.com/rosenberg/2226-verdict) on their espionage charges
Comment: You can read the entire text of the Espionage Act as amended at [18 USC 791-799](https://www.law.cornell.edu/uscode/text/18/part-I/chapter-37); it's not that long.  I see nothing at all about jury trials, so there's certainly no ban "written into" the Act - and even if there were, it would be unconstitutional and void under the Sixth Amendment which contains no exceptions.
Comment: Likely due to the classified nature of the evidence.
Comment: It's true that jury trials *rarely* occur in espionage cases, but AFAIK that's just because the government tries very hard to plea-bargain to avoid a trial where classified evidence might have to be disclosed.  I imagine it is not hard to strike a bargain when the government offers a sentence of twenty years, if the other option is going to trial with the death penalty on the table.
Comment: There is a right to a jury trial. The right to have that jury trial conducted in public can yield in whole or in part to other considerations, however.
Answer: There is no exception arising from the Espionage Act, indeed in Gorin v. US, 312 U.S. 19, one of the holdings is that "In a prosecution under §§ 1(b) and 2 of the Espionage Act, the jury determines whether the acts of the defendants were connected with or related to the national defense under proper tests laid down by the instructions". This does not mean that the prosecution will not be eager to avoid the possibility of jury nullification and may hope for a bench trial. Here is the transcript of the jury verdict in the trial of the Rosenbergs, and another report of an espionage conviction in a trial by jury. There is no evidence that Assange "would not be afforded a trial by jury" if he requested it.
Answer: Here is an article explaining how difficult it is to defend oneself in a whistleblower or leaker trial setting under the Espionage Act. That means that one's chances of receiving an acquittal if one goes to trial rather than accept a plea deal drop close to 0. In fact the Eastern VA District Court has NEVER acquitted anyone brought to trial for a whistleblower offense. Thus the de facto conclusion is that a jury trial is for all intents and purposes not an option for such defendants. https://freedom.press/news/if-snowden-returned-to-us-for-trial-all-whistleblower-evidence-would-likely-be-inadmissible/


Challenges when trying to build a telescope using two lenses

Question: I have some lenses - a 10 cm and 7 cm convex lense and a 4 cm and 1 cm concave lenses. I am trying to make a telescope by combining one of convex and concave lenses, but I am struggeling to do so. The picture that is created using these two lenses doesn't show anything other than the thing that can be seen by eyes. Is it possible to make simple telescope using these lenses?
PS: All of numbers are lense diameters.
Answer: Diameter is important, but if you're trying to get any magnification out of that system, you need to look at the focal length.
If you have a very distant light source, like the Sun, focused through a convex lens, until the image of the source is as small and as clear as possible, then the focal length is the distance between the lens and the image you're creating. Like when you burn paper with the lens, focal length is the lens-paper distance.
For concave lenses focal length is a little more tricky to define, but they do have a focal length anyway.
If F is the focal length of the forward lens (the objective), and f is the focal length of the lens near your eye (the ocular, or the eyepiece), then the magnification of the instrument is:
M = F / f
So you need an objective with a long focal length, and an eyepiece with a short focal length.
Both the objective and the eyepiece could be convex actually. It's just that the image will be reversed. If the eyepiece is concave, the image will be straight-up, but the field of view of the telescope will be narrow (like looking through a peephole).
If you use both convex lenses, the distance between them need to be close to the sum of their focal lengths, F + f. Start there and adjust it slightly for best results.

If you use a concave lens for the eyepiece, then the distance between lenses needs to be the difference of their focal lengths, F - f.

Both lenses need to be perpendicular on their common axis, to minimize aberrations.
It helps if they are mounted in a tube, to reduce glare, but it's not absolutely necessary. They could simply be attached to a long rod or something - but you'll get a lot of glare into the eyepiece that way.
Do not necessarily try to get very high magnification. If the diameter of the objective is D, measured in mm, then the maximum usable magnification is 2D. So an objective 100 mm in diameter could never provide more than 200x magnification - I mean it could, but the image would be blurry. Even then, this is a theoretical limit, and in practice the image will get pretty bad long before you reach the limit, unless you use high quality lenses designed specifically for telescopes, etc. Also, at high magnification it's difficult to hold the scope steady, and the image is jumping all over the place.
Try and make a 5x ... 8x instrument first, see how that goes. A lot of binoculars are in this range.
I've built several refractor telescopes from lenses when I was in high school. It's totally doable. It just takes some patience to figure out how to solve all problems.
Comment: Don't forget the Galilean configuration using the negative lenses for the eyepiece; https://en.wikipedia.org/wiki/Refracting_telescope#Galileo.27s_telescope One advantage is that it gives an erect image.
Comment: the f of 10cm convex lens is 30 cm and for 1cm concave lens is 20 cm. so M is 1.5 that I think is too low. should I provide other lenses?
Comment: @user123 - Yes, try and find a lens with a focal length around 4 ... 6 cm and see how that goes. I believe regular magnifying glasses have focal lengths in that range, usually.
Comment: Another thing that would work is an eyepiece (ocular) recovered from an old, broken telescope, microscope or binoculars. Typical focal lengths vary in the 4 mm ... 55 mm range, so see if you can find an eyepiece on the longer side of the interval (a.k.a. "weaker" eyepiece). Then there are lenses used by people who do miniature work, such as watchmakers; one of those should work too. Finally, the lens assembly from an old photo or video camera might do the trick; perhaps it will work as-is, or perhaps you can extract the individual lenses and see which one is right for you.
Comment: focal length of 4cm is enough? I thought that it should be around 1 meter.
Comment: 1 meter would be great for the objective. For the ocular (eyepiece) you need something in the centimeters range.
Comment: i founnd some lenses with magnification of 40x, 30x,60x, 10x,4x, 5x, .. which is better?
Comment: For objective you want a lens with a long focal length, or smaller magnification. For the ocular (eyepiece) you want a lens with a short focal length, or higher magnification.


Check if feature is selected (Openlayers)

Question: I wonder if there is a way to check whether a pointfeature (OpenLayers.Feature.Vector) is selected. I read the API, but didn't find any solution. Any idea?
Comment: See http://openlayers.org/dev/examples/select-feature.html
Answer: After a feature is selected, it's added to the vector layer's selectedFeatures array (and removed after it's deselected)

You can test it in your browser: http://openlayers.org/en/latest/examples/select-features.html

Draw a polygon
Open JS console (i.e. Firebug or Chrome dev tools)
Type:

var vectorLayer = map.getLayersByName("Vector Layer")[0];
var feature = vectorLayer.features[0];
vectorLayer.selectedFeatures.indexOf(feature);

=>  -1 // (i.e. not selected)

Select the polygon and check again:

vectorLayer.selectedFeatures.indexOf(feature)

=>  0 // (i.e. the polygon is selected)
Answer: For newer Openlayers 3 the array is not kept in the Layer any longer. You can get by the interaction.select itself:
//get features as collection
var features=interaction_select.getFeatures();
//get length (.length doesnot work in my case)
var int_features=features.getLength();
//or access by numeric index like any collection
var first_item=features.item(0);

If you want to read more about interaction or the collection then just begin there: http://openlayers.org/en/v3.7.0/apidoc/ol.interaction.Select.html#getFeatures


Logs, Risk/Issue Log

Question: How does one create a Log of various discussion points on SharePoint?  How does another user add comments to a specific point on the Log?  Is there a Template for SharePoint users to upload that is a Log format?
Answer: There are no list templates from Microsoft for this purpose. Various products (free or paid) provide this functionality. I prefer creating a custom list and add a column 'Comments' with type 'Multiple lines of text' (set the option 'Append Changes to Existing Text' to 'Yes'). You need to enable versioning for this list otherwise this field will only capture the last comment.

Logs, Risk/Issue Log


How do you reduce the size of a folder's index file in NTFS?

Question: I have a folder in NTFS that contains tens of thousands of files. I've deleted all files in that folder, save 1. I ran contig.exe to defragment that folder so now it's in 1 fragment only. However, the size of that folder is still 8MB in size. This implies that there's a lot of gap in the index. Why is that? If I delete that one file, the size of the index automatically goes to zero. My guess is because it gets collapsed into the MFT. Is there any way to get NTFS to truly defragment the index file by defragmenting it based on the content of the file? Any API that you're aware of? Contig.exe only defragment the physical file.
Answer: I guess this is one way in which NTFS is just like almost every other FS - none of them seem to like shrinking directories.
So you should apply a high-tech method that involves using that advanced language, "BAT" :)
collapse.bat
<code>REM Invoke as "collapse dirname"
ren dirname dirname.old
mkdir dirname
cd dirname.old
move * ../dirname/
cd ..
rmdir dirname.old
</code>
Comment: that is disgusting. but pretty damn clever :)
Answer: There is slack in the index, but not a gap.  I make the distinction to imply that there is technically wasted space, but it's not like NTFS has to parse the 8MB in order to enumerate/query/whatever the index.  It knows where the root of its tree is, and it just happens to have a lot of extra allocation leftover.  Probably too detailed a response, given how unhelpful it is.
Fragmentation is likely a separate issue altogether.
Answer: Take a look at the accepted answer to this question: NTFS performance and large volumes of files and directories
The author provided some otherwise undocumented information about file index fragmentation, which he received from Microsoft Tech Support during an incident. The short version is, DEFRAG does not defragment the folder index, only the files in that folder. If you want to defragment the file index, you have to use SysInternals' CONTIG tool, which is now owned and distributed (free) by Microsoft. The answer gives a link to CONTIG.


USB OTG: Possible to perform emulation of slave device on master with drivers recognized?

Question: I'm planning to build a device using either a Raspberry Pi A or Radxa board with the aim of emulating a slave device (unified keyboard and mouse) via commands sent by the board (possibly by a slave device to the board? or a network protocol). As I understand from the specifications of the two boards, there are USB OTG ports that allow for acting as a slave device, however from my knowledge, USB OTG only allows a fixed set of functions as a slave device. Is it possible to make the specific USB port I wish to perform emulation from slave-only considering it is an OTG port? Also, how do I handle driver recognition in this case? Where is the firmware embedded for USB OTG?
Comment: I think you misunderstood USB OTG. OTG is slave to slave connection and slave emulates host.
Comment: OTG is when a device which is normally a slave becomes a (limited function) master. Do you just want to build a slave device (a composite keyboard / mouse)?
Comment: @user1448742 Hello, thank you for the answers. Yes, I appears I've misunderstood that USB OTG is not a host emulating a slave but rather the other way around.
Comment: @brhans I want to build an interface that will allow output from one slave device to "pass through" the interface to output on the other end, as a slave device input. The idea may sound stupid (why don't just use a USB extension cable?) but there is a very real reason for this. The interface must thus be able to a) accept input from a slave device, and at the same time b) emulate this output as though it as a slave device.

I may have found a means to do this via software, but how do I implement slave device firmware on the interface device for the host to recognise? OTG seems to be limited...
Answer: Ok, so you need a device with at least 2 USB ports. One of these must be a slave port which you will connect to a host PC and the other port must be a host which you will connect a keyboard/mouse/whatever.
Your device will then enumerate and handle the slave device(s) on its host port, process any information and/or events from these devices, and then forward this data out of its slave port up to the host PC.
So to answer your question simply: yes this is possible.
But, I don't think its going to be possible with either of the boards you're looking at.
The one half would be fairly straightforward. These boards would be quite happy using one of their USB ports to talk to your keyboard/mouse device(s).
The problem comes about when you want to use them to emulate a particular type of slave device to your host PC.
These kind of boards are typically configured to provide a very limited selection of USB profiles to choose from when connecting them to a PC (such as a mass-storage device, serial port emulation, camera or possibly some kind of debugging interface) and you'd find it quite difficult to change this to look like something else - in your case a HID device like a keyboard and/or mouse.
I'm not saying its impossible, but I don't know enough about these boards and its not obvious from their simple overviews that they support this.
This is the kind of application where you will probably need to work at a lower level - more directly with the firmware on a suitable microcontroller or microprocessor.
If I were to try to pull something like this off, I'd be inclined to set up a pair of microcontrollers back-to-back. One of them is the USB OTG host to your keyboard/mouse, the other one acts as a keyboard/mouse compound device to your host PC, and they're connected to each other using SPI.


Late 90's YA Alien Book

Question: Trying to find a book a read in the late 90's. Young Adult fiction story about aliens secretly coming to earth & the main characters trying to stop them. I recall it surrounding TV towers and power lines
Comment: Can you remember anything about the cover?  What is the country of origin?
Comment: And what exactly is surrounding these towers and power lines? The alien? Their ship? The cover art?
Answer: This might be "You Remember Me" by Nicholas Fisk, or it's prequel "Grinny", or a 2-in-1 of both. My memory's a bit hazy, but I read them in the early or mid 90s.
"aliens secretly coming to earth & the main characters trying to stop them." - check. In both books, one alien had arrived in advance, disguised as a human, to start infiltrating society and preparing the humans for obedience. I don't remember if it was the same alien in both. The alien was sufficiently capable of hypnosis to have rendered most of the adults incapable of detecting or doing anything about them - only the children who were the protagonists could.
"surrounding TV towers and power lines" I do know the aliens were scared of electricity. In the first book, the children forced the alien to hold a (live) power cable - this was an unpleasant (traumatic?) enough experience for the alien to flee Earth as soon as they let it go. In the second book, the infiltrating alien had successfully created a mass media persona and was making a lot of TV appearances.

Late 90's YA Alien Book


What temporal resolution for time series significance test?

Question: I need some guidance on the appropriate level of pooling to use for difference of means tests on time series data.  I am concerned about temporal and sacrificial pseudo-replication, which seem to be in tension on this application.  This is in reference to a mensural study rather than a manipulative experiment.
Consider a monitoring exercise:  A system of sensors measures dissolved oxygen (DO) content at many locations across the width and depth of a pond.  Measurements for each sensor are recorded twice daily, as DO is known to vary diurnally.  The two values are averaged to record a daily value.  Once a week, the daily results are aggregated spatially to arrive at a single weekly DO concentration for the whole pond.
Those weekly results are reported periodically, and further aggregated – weekly results are averaged to give a monthly DO concentration for the pond.  The monthly results are averaged to give an annual value.  The annual averages are themselves averaged to report decadal DO concentrations for the pond.
The goal is to answer questions such as:  Was the pond's DO concentration in year X higher, lower, or the same as the concentration in year Y?  Is the average DO concentration of the last ten years different than that of the prior decade?  The DO concentrations in a pond respond to many inputs of large magnitude, and thus vary considerably.  A significance test is needed.  The method is to use a T-test comparison of means.  Given that the decadal values are the mean of the annual values, and the annual values are the mean of the monthly values, this seems appropriate.
Here's the question – you can calculate the decadal means and the T-values of those means from the monthly DO values, or from the annual DO values.  The mean doesn't change of course, but the width of the confidence interval and the T-value does.  Due to the order of magnitude higher N attained by using monthly values, the CI often tightens up considerably if you go that route.  This can give the opposite conclusion vs using the annual values with respect to the statistical significance of an observed difference in the means, using the same test on the same data.  What is the proper interpretation of this discrepancy?
If you use the monthly results to compute the test stats for a difference in decadal means, are you running afoul of temporal pseudoreplication?  If you use the annual results to calc the decadal tests, are you sacrificing information and thus pseudoreplicating?
Comment: You question is rather tricky... I'm thinking in it.
Answer: I believe that you are trying to use statistical methods that are appropriate for independent observations while you have correlated data, both temporarily and spatially. If you have observations say for 5 hours and decide to re-state this as 241 observations taken every minute, you really don't have 240 degrees of freedom in respect to the mean of these 241 values. Autocorrelation potentially yields an overstatement of the size of "N" and thusly creates false uncertainty statements. What you need to do is to find someone/some textbook/some web site/.... to teach you about time series data and it's analysis. One way to start is to GOOGLE "help me understand time series" and start to read/learn. There is a lot of material available on the web. One available  trove of time series information is something I helped create at http://www.autobox.com/AFSUniversity/afsuFrameset.htm . I mention this as I am still associated with this firm and it's products thus my comments are "biased and opinionated" but not solely self-serving.


Do light dimmers save energy and lower your electric bill?

Question: Or do they just capture the incoming energy and turn
it into heat at the unit and save you nothing?
Comment: I'm voting to close this question as off-topic because it is about the features of a device which is unrelated to physics.
Comment: In the old days dimmers were rheostats, adjustable resistors, so they dimmed the lights but did not save any energy. Today they do both, and they are most often implemented via pulse width modulation.
Comment: A light dimmer is not a resistor.  It works by switching the power on and off.  In the the max-brightness setting, the power will be on 100% of the time.  In the min-brightness setting, the power will be on about 50% of the time.
Comment: I think they save energy. A good inductor can reduce current without dissipation of energy, and hence reducing power consumption.
Comment: I understood that pulse width modulation was quite destructive for various sort of light sources (but the regular filament bulb) ?
Answer: Yes, dimmers save energy.  Modern dimmers save more energy than older (rheostat) dimmers, but both save energy.
Modern dimmers use a "triac", which is an inexpensive way of reducing power by pulsing the current.  These pulses result in lower average current going to the bulb, and therefore lower average power.  They are very efficient, so providing current 50% of the time implies using about 50% less current, or 50% less energy overall.
Older dimmers used rheostats, which are basically just resistors.  These are less efficient but reduce energy.  Consider the case of a bulb with resistance $R_B$ in series with a rheostat of variable resistance $R_V$.  The total resistance is then $R = R_B + R_V$, and the total power is $P = {{V^2}\over{R}} = {{V^2}\over{R_B + R_V}}$.  So if the rheostat is set to $0\ \Omega$, then  $P = {{V^2}\over{R_B + R_V}} = {{V^2}\over{R_B}}$, and if it's set to the same value as $R_B$, then $P = {{V^2}\over{R_B + R_V}} = {{V^2}\over{2R_B}}$, or half as much power into the combined resistors.  Note though, that while the total power goes down by two when dimmed (with these values), so dimming uses less power overall, the power to the light goes down by four, because half of the total power is lost in the rheostat... and that's why rheostats are inefficient.
A further complication to this with incandescent bulbs is that they are less efficient at producing visible light when operating out of their designed range since a larger proportion of energy ends up in the infrared range.  That is, if you dim a single bulb to get less light it uses less energy than undimmed; but even with a 100% efficient dimmer, if you combining multiple dimmed bulbs they will use more energy than a single undimmed bulb, for the same amount of visible light.  Or said another way, if you want less light, it's more efficient to use a bulb designed for less light -- and this will always be true due to the usual inefficiencies, but is exaggerated for incandescent bulbs.


Run rate of 20 over Cricket match

Question: In 20 over game.... first team scored 152 all out in 16.2 Over and second team scored 153/6 in 17 over.what is the run rate?
Answer: The team batting first will always have their run rate calculated for the maximum number of overs they can bat irrespective of the number of overs they have managed to play.
As in this case, the first team NRR is  7.6 (152/20).
For the second team NRR is dependent on various scenarios.

Played for 20 overs without getting all out.In this scenario NRR is
calculated for entire 20 overs.
Chased the target with overs remaning. NRR is calculated for only
the played overs.
Got All out before 20 overs. NRR is calculated for entire 20 overs.

Hence in your case the second team NRR is 9 (153/17)

Run rate of 20 over Cricket match


Erlang - Standard location of mnesia database

Question: Is there a standard place to put the mnesia database within erlang? At the moment I am putting it in the priv directory.
Answer: By default, Mnesia will create the schema in a subdirectory called Mnesia.<node name> of the current directory of the emulator process.
If that's not what you want, all you need to do is set Mnesia's dir application variable with something like
application:set_env(mnesia, dir, "/path/to/db").

As for where to place the database: that depends on your deployment scenario. Since application
variables can also be set using release config files or command line arguments, you can delay that
decision until you ship (or install on your own servers). For use in production, a standard directory like /var/lib/<your application>/mnesia-<node name>(on unix) should do.
For playing around, i'd recommend using a dedicated directory under the code root (NOT the priv directory) and setting that location within your application's startup section.
In my pet projects, i often use code such as
Root = filename:absname_join(filename:dirname(?FILE), ".."),
application:set_env(mnesia, dir, filename:join(Root, "db")).

for exactly that purpose.
Answer: As far as I know, when you create the schema every node creates a schema directory in its root directory.
Therefore, I guess that can be considered the default location.
If, for some reason, you have to include a schema together with your application, well, I guess the priv folder should be fine, since it is supposed to be used for application specific files and it's easily accessible via the code:priv_dir/1 function.


Why does my ceiling fan light turn off by itself?

Question: I have a remote-controlled ceiling fan and light.  I don't run the fan, but when I turn the light on sometimes it will stay on for a long time then just go off by itself.  I have tried both kinds of bulbs, but neither works.  What causes this problem.  Do I have to replace the ceiling fan and light, or can it be fixed?
Comment: By "remote," do you mean that it has an infrared remote control, like a TV? How is the fan wired—are there any wall-mounted switches that control the fan? How long does it stay on before it turns itself off? Does that only happen sometimes?
Comment: does the light come back on by itself after it is off for awhile?
Comment: It would be useful to test with the fan on as well, knowing if that turns off at the same time or not will help isolate the problem to the light part (or not).
Comment: Is it overlamped, with a bulb that's a higher wattage than what it's listed to supply? Lots of devices have thermal sensors that kill power to the light if it heats up too much. (A bit of darkness beats a fire.)
Answer: I bought 2 Hunter Exeter model fans and was running into the problem of the lights cutting in and out after about 10-15 minutes of steady light output.  Both fans were having the same problem. The fans are controlled by radio frequency remote controls - which the instructions say are "paired" with the fan when they arrive.  BUT, you can re-pair them and doing so solved my intermittent light problem.  I only re-paired one of the fans and now both fan lights work properly.  My guess is there was some interference between the remotes for the two fans, and re-pairing one eliminated that interference.
Answer: I had a ceiling fan where the light turned off after it heated up, it turns out that the contact that the bulb screws into lost contact due to the expansion of the metal due to the heat. You could try bending the contact out a bit to see if that helps. Clean it as well while you're at it. Make sure the power to the light is off so you don't get a shock.
Another possibility is that the radio control is being activated by interference or someone else using a remote on the same frequency. Many devices like doorbells and garage door remotes use the same radio technology, so changing the radio channel your light uses may fix the problem. Your manual should show how to do that.
Comment: Don't just flip the switch off. Kill power to the entire circuit at the breaker box before bending out the contact. That, or *very carefully* use a listed insulated tool. If someone wired the light wrong (interrupting the white, grounded conductor rather than the black), the socket will still be hot even with the switch off.
Answer: A lot of these ceiling fan lights have a wattage/voltage protectors. If the combined wattage of the bulbs exceed 190 watts, it will shut down the lights. Try using 40 watt bulbs, not 60.  I just had this happen to me
Answer: I installed an outdoor Hunter ceiling fan 8 days ago (lantern model) that came with the 2 dimmable LED bulbs so the bulbs are not overheating.  It also came with the 2032CR watch battery for the remote control.  Occasionally when I use the wall switch to turn the fan & light on and off instead of using the remote control to control the fan and light on and off from it's previous setting I have that problem.
I opened the remote control, pressed the reset button and haven't had the problem the last 3 days.
Answer: I just had the same issue where every time I used the remote to turn on the lights, it would go off the very next second. Fan would stay on and speed can still be adjusted. I took the remote apart thinking maybe the light button got sticky. Then I unplugged the light assembly under the glass covering. None of it helped. Only when I took one bulb out, the other one would stay on. So it is definitely the wrong bulbs being used.
Answer: It's because you have the wrong wattage light bulbs in there. Take one out and it will come on and stay on.


Is it possible to transfer from Sun/Moon to X/Y?

Question: My daughter has the game Sun and Moon, she just got the game X and Y, she is trying to transfer her pokemon from Sun/Moon over with the bank-transfer app but when she goes to move them over it tells her she is unable to move that character, any suggestions please?? Thank you!
Answer: Unfortunately that is not possible.
You can transfer Pokémon from X/Y/OR/AS to Pokémon Sun/Moon through the Pokébank and you can put Pokémon from Sun/Moon on the Pokébank.
Unfortunately, any Pokémon that has been in a Sun or Moon game cannot be transferred to a 6th generation game (Omega Ruby, Alpha Sapphire, X or Y) even if it is the game it originally came from
It's unfortunate but avoids a lot of potential compatibility problems.
This answer to a similar question has the official picture detailing Pokébank capabilities for all the versions starting with the DS games. You should have a look if ever you wish to buy an older game.
Answer: It is possible so long as it has no new data, meaning that as long as it hasn't got any moves, ribbons or any other marking not possible in X/Y/or/as it is entirely possible to re-use it in gen 6.
I've even done so for breeding sake since x/y was much quicker at getting the tedious stages of IV breeding done to then finish off on gen 7 for tournament legality


Blender Python Advanced Panel in 3d Space

Question: Have you got any ideas on how to achieve this kind of interface that pops up at the 3d space?
This image is from the archipack addon.

I've read the script and the panel itself is found on the 3d space UI and wondering how he created this type of panel with layout design and interactive buttons inside the panel.
Answer: You have to draw the interface yourself in a modal operator. See the modal operator template in the text editor, and use the bgl module to do the drawing.
Answer: Archipack's sample may be overkill, as it does override regular preset_loader operator and hide bgl logic behind an abstraction layer.
archipack_presets.py and archipack_gl.py
You may take a look at asset flinger implementation.
Asset flinger github repo
As a side note, bgl module is currently not supported in 2.8 series and a complete rewrite is planed, so this api is likely to change.


HOW do I do performance testing on a web app (manually)?

Question: It is an interview question, and I did not know how to tackle it. do I go to DevTools and check its performance? what kind of tools do I use?
Comment: Performance testing is an umbrella term (and I don't need to say how open "web app" is).
I suggest giving more details about the web app itself described in the interview and what exactly was the testing mission (related to the performance) - What information do you wanted to check? What risks do you want to explore? What metrics do you want to extract?
Answer: Be honest with the interviewer and about knowing your own experiences, skills, and what you are lacking. If you know you have missing skills and can admit it in an interview, this shows self-awareness. Self-awareness is not a weakness, but shows confidence! A lot of people will say "make something up" or "just fake it," but that tends to show with a lack of confidence. And if you get the job and they expect you to do performance testing, then you're playing from behind and still need to own up to not knowing this skill. So, it's best to be honest upfront. Areas where you a lacking, be sure to also answer with how you plan on learning about this skill!
Now, if you have some knowledge, then answer with what you know. You seem to know about performance testing features in the browser dev tools. It seems like your perspective is on the front-end or with web apps. So your answer is:

"While I don't have a lot of experience in performance testing, I do
know it's an important skill to have. What I've done in the past is to open
the browser's DevTools and use the Performance Profiler. I also have
used Google's Lighthouse to perform a comprehensive report. I take the
information I learn and work with the dev team on correcting the
issues found."

You can also give more details on how you work with the dev team. Is it just informal conversations about your findings? Are you writing bugs or stories for these concerns? Are you running a discovery meeting with the team to go over solutions? Explain these details. This is how you give a comprehensive answer that shows your knowledge, skills you're willing to learn, how you work with a team, how you share knowledge, etc. And when you're comprehensive like this, your confidence will come through!
Remember, interviewers aren't necessarily looking for a "perfect" answer, but they do want you to extrapolate on your skills, experience, how you work on a team, how you learn, etc.
Other aspects to this question:
Performance testing can be done at any level of software: web apps/front-end, backend, APIs, databases, etc. So, a more experienced answer should include these areas.
If you have any knowledge of performance testing tools/services, regardless of if you've used them, you can answer with those as well. Something like:

"I don't have a lot of experience, but I do know about tools like
JMeter, K6, etc. There are both local tools and cloud-based tools."

Here, you can give details on the pros/cons of the differences between local/cloud tools. You can also do a cost-benefit analysis of free/open-source tools versus paid tools.
You can also ask the interviewer to clarify what they mean by performance: what level of the stack? Are they looking for stress testing, load testing, soak testing, etc?
Interviewers tend to give broad/general questions, so it's up to you to ask for clarification. Some interviewers ask questions because they are in need of certain skill sets immediately. So, this allows you to pry into what problems they are having. In addition to the above, you can also ask them:

Is the team experiencing performance issues currently? What are they?
Are customers complaining/leaving due to performance issues?
Does the team use any performance testing tools currently?
How is DevOps involved with performance testing? (At some companies, QA doesn't do performance testing, but DevOps will!)
Do you expect performance testing to be done in production or in non-production environments? (This allows you to determine the level of risk they are willing to accept!)
Are you willing to pay for tools to help with performance testing?
Are there any monitoring tools setup to log or alert on performance issues in production?

Hopefully, this helps for next time you encounter this question. And, points you in a direction to learn new skills!
Answer: By using browser developer tools you can only inspect individual requests response times using "Network" tab and get in-depth information on page loading, rendering and scripts execution timings using "Performance" tab. See https://profiler.firefox.com/ for example
It's also possible use 3rd-party solutions like WebPageTest or Lighthouse
All above applies only to frontend, if you need to assess your web app performance under the load (when it's being used by multiple users at the same time) you will need a load testing tool which is capable of simulating real users activities.


migrate drupal site , error occured, the site was down

Question: I migrate my site from WinServer2003 to CentOS ,  with the following step:
1. migrate the database to the CentOS server with .sql files backup.
2.copy all the website root file to the new server.
when i  visited some node an error occured:

according to the message  there was a table or view was missing, but there was no such a table or view in the old system(win2003)
how can i fix the problem, any suggestions are appreciated, Thanks in advanced.
when i do some config (i delete the text format: filter HTML), the site  was completely down.
 when visit it just show an error:

i am really confused.
Answer: I solved the problem,  the link : https://www.drupal.org/node/1882292  i just follow the #11 's method and create the image_dimensions table.


Easiest place to find loot Goliaths and make god-liaths

Question: I've looked at a lot of places all over the place, like Sanctuarys hole and had no luck, except for two Goliaths.  I am a level 18 assassin, mainly use snipers, shotguns, and revolvers on occasion I use SMGs.
Comment: i remember seeing some in frostburn canyon and also on the slab king's initiation quest.
Answer: Loot Goliaths are just rare forms of the standard Goliaths, so the best place to farm them is wherever you find Goliaths.  Tundra Express has several large bandit encampments, and I tend to find them and the slot machine Goliaths regularly on this particular map.  (In fact, I found one just last night right outside Tiny Tina's...)
Since they're rare, you're not going to see them often.  I don't think they're particularly good for farming loot compared to other methods, given their rarity.
Farming a God-Liath requires that you have a somewhat powerful Goliath, and enough enemies to level him completely up.
Good spots to farm these guys balance three factors:

If the Goliath is too weak, he'll lose to the enemies
If there aren't enough enemy spawns, he won't level up enough
If he's too tough, you won't be able to kill him after he maxes out

Again, there are a lot of bandits in Tundra Express.  I don't like Frostburn Canyon for this because the flamethrower nomads tend to make short work of Goliaths.  When I did this for the achievement, I did it twice in Eridium Blight.  There's a fairly large encampment of bandits up on the hill near Grandma's House.
Comment: Thank you I appreciate it and I had a god liath way to high just today he was level 28
Answer: From comments at the Reddit - /r/Borderlands post, "No... DON'T kill the Goliaths!!" (I added the links to the Borderlands wiki):

...I ran into a Loot Goon Goliath at the start of Hunting the Firehawk. I kited him all the way around Frostburn Canyon, all the way up to the entrance to her lair, letting him kill anything that got in our way.
...Frostburn Canyon is a great place for kiting them around to level them up. I always get a God-liath going and let him kill Scorch for me.

and

The best time to make a GOD-liath is the Slab initiation. He literally did all the work. Also, in True Vault Hunter, I did a showdown to see who will become the toughest Goliath.
I love the Once and Future Slab mission. I just pop the tops off all the Goliath's then grab some popcorn and settle in for some mayhem.
Answer: Best place is at the Firehawk area u get a Goliath there they are immune to fire get a corrosive weapon hurt the bigger guy and he will fame the psycho and spiderling like crazy


What does the term Other Revenue mean?

Question: I am looking at Target's recent earnings release which can be found at the following URL:Earnings Release.
On page five it show two types of revenue: sales and other revenue. What does other revenue represent?
Answer: It means revenue from other business activities that aren't substantial enough to warrant their own line items.
Target's latest 10-K provides some detail about what is included:

Other – Includes advertising, Shipt membership and service revenues,
commissions earned on third-party sales through Target.com, rental
income, and other miscellaneous revenues.
Answer: Are you asking "What specifically does Target mean by Other Revenue" or are you asking "What might a company like Target mean by Other Revenue"?  Given that Other Revenue appears to be only 1.5% of Sales, it is unlikely that Target provides a specific breakdown of the types of other revenue they might receive.  Typically, companies would provide more detail in annual reports than in quarterly reports.  So if you go back to the 2021 annual report and go to page 11, there is this paragraph

We also sell merchandise through periodic exclusive design and
creative partnerships, and shop-in-shop experiences, with partners
such as Apple, Disney, Levi's, and Ulta Beauty, and generate revenue
from in-store amenities such as Target Café, Starbucks, and Target
Optical. CVS Pharmacy, Inc. (CVS) operates pharmacies and clinics in
our stores under a perpetual operating agreement from which we
generate annual occupancy income.

At least some of their Other Revenue comes from CVS leasing space in Target stores for pharmacies and clinics.  Realistically, they're also getting revenue from these other partnerships.  In any given quarter, they might recognize revenue from other random sources-- selling land they had purchased, gains on currency hedging transactions, etc.
Comment: I am asking:  "What might a company like Target mean by Other Revenue"?
Answer: Generally, companies talk a lot about their mainline revenue sources, i.e. revenue that derives from the business they are trying to be in.
However, you get incidental revenue from every darn thing. Say you buy a parcel of land for a future distribution center, and the land has a USDA conservation easement (in which USDA pays you a small amount not to farm it).   But, the plans do not pan out that year.  You take the USDA income with a smile, it is 0.002% of your total revenue.
But now, you are writing your annual report to stockholders in which you describe your revenue in a limited number of words.  Are you going to take 3 paragraphs explaining what the USDA program is, which properties benefit from it, state the pittance it earns, and then open the can of worms of why you own farmland and why the distribution center is not being built? Absolutely not in a general report.
Other random income sources are things like easements, sublets (buying a strip mall to get the anchor store location, or CVS at Target), tax abatements or tax credits (say that rooftop solar system you installed in the San Bernadino location), etc.
It's just the random effluvia of being in business, and it isn't worth wasting the stockholders' time to break it all out.  Of course if someone asks, you'll give them chapter and verse.
Comment: Presumably your last sentence depends on the definition of "someone." If someone is an auditor, the authorities investigating tax or compliance matters, an acquirer doing due diligence, then sure, they'd go into detail as required. If someone is a random holder of 5 shares of Target who calls up asking about the details of random transactions, they'll tell them that the information in the report is the most detailed that is available to the public. (Shareholder rights to access books and records do exist, but aren't usually available just to poke around at immaterial stuff for curiosity.)
Comment: @ZachLipton I don't know for sure what would happen if a company tried to deny access to that information to a shareholder.  But I would consider such withholding *unwise and provocative* unless there was an airtight case that the guy has ill-intended motivations toward *the company*.  The problem is, management can never see that, because it's almost guaranteed that the guy has ill intentions *toward management*, and I've never met a management that didn't think they and the company are the exact same thing.

What does the term Other Revenue mean?


Is it a bad idea to allow magento upload SVG file for CMS page?

Question: One of my user request to ask me to make the Magento able to upload svg file to the CMS. I did some research, some say security issue, but didn't tell much what kind of security issue it may happen. Anyone can give me a clear advice? Thanks
Answer: It depends.
So if you let your admin upload it, or say it another way, the trusted users upload it then it's alright, no problem.
Handling that to users who we don't know, therefore, cannot be trusted is dangerous.
I myself haven't implemented the upload svg guard but you may check this answer, it listed several ways to help prevent the risk
https://security.stackexchange.com/a/192736


memory allocation in small memory devices

Question: Some systems such as Symbian insist people to use heap instead of stack when allocating
big objects(such as pathnames, which may be more than 512 bytes). Is there any specific reason for this?
Answer: Generally the stack on an embedded device is fixed to be quite small i.e. 8K is the default stack size on Symbian.
If you consider a maximum length filename is 256bytes, but double that for unicode that's 512bytes already (1/16th of your whole stack) just for 1 filename. So you can imagine that it is quite easy to use up the stack if you're not careful.
Answer: Most Symbian devices do come with an MMU, but, until very recently, do not support paging. This means that physical RAM is committed for every running process. Each thread on Symbian has (usually) a fixed 8KB stack. If each thread has a stack, then increasing the size of this stack from 8KB to, say 32KB, would have a large impact on the memory requirements of the device.
The heap is global. Increasing its size, if you need to do so, has far less impact. So, on Symbian, the stack is for small data items only - allocate larger ones from the heap.
Answer: Embedded devices often have a fixed-sized stack. Since a subroutine call in C only needs to push a few words onto the stack, a few hundred byte may suffice (if you avoid recursive function calls).
Answer: Most embedded devices doesn't come with a memory management unit so there is no way for the OS to grow the stack space automatically, transparent to the programmer. Even assuming a growable stack, you will have to manage it yourself which is no better than heap allocation and defeats the purpose of using a stack in the first place.
Answer: The stack for embedded devices usually resides in a very small amount of high-speed memory. If you allocate large objects on the stack on such a device, you might be facing a stack overflow.
Comment: You mean to say that stacks are generally allocated in cache?


HTML meta keyword/description element, useful or not?

Question: Does filling out HTML meta description/keyword tags matter for SEO?
Answer: This article has some info on it.
A quick summary for keywords is:
Google and Microsoft: No
Yahoo and Ask: Yes
Edit: As noted below, the meta description is used by Google to describe your site to potential visitors (although may not be used for ranking).
Comment: The "description" meta information is used by Google when describing your site, so its not completely pointless.
Comment: Doesn't the description meta used when no DMOZ description (or explicity specified) is available ?!
Answer: Google will use meta tags, but the description, to better summarize your site.  They won't help to increase your page rank.
See:
http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=79812
EDIT: @Petr, are you sure that meta tags influence page rank?  I am pretty sure that they don't, but if you have some references, I'd love to learn more about this.  I have seen this, from the Official Google Webmaster Central Blog, which is what leads me to believe that they don't:

Even though we sometimes use the
  description meta tag for the snippets
  we show, we still don't use the
  description meta tag in our ranking.
Comment: I think he means that if you put a good description users are more likely to click. People clicking your link **does** increase your page rank, because it tells google people are interested. As a **very indirect** effect the person who clicked only because of your great description may link to your website from theirs, therefore increasing your page rank even more.
Comment: It can increase page rank as a secondary effect.
Comment: @Petr, would you care to elaborate?  I have edited my answer with more information as to why I thought that was not true.
Answer: Keywords: Useless
All major search engines don't use them at all.
Description: Useful!
Replaces the default text in search engines if there isn't anything better. Use this to describe the page properly. Not perhaps useful for SEO, but it makes your results look more useful, and will hopefully increase click through rates by users.
Answer: If you want your users to share your content on Facebook, the meta tags actually come in handy, as Facebook will use this information when styling the post.
See Facebook Share Partners for more information.
Edit; whoops, wrong url. Fixed.
Answer: If your pages are part of an intranet then both the keywords and description meta tags can be very useful. If you have access to the search engine crawling your pages (and thus you can specifically look for sepcific tags/markup), they can add tremendous value without costing you too much time and are easy to change.
For pages outside of an intranet, you may have less success with keywords for reasons mentioned above.
Answer: The description meta is important as it is displayed ad-verbatim on Google search results below your site title. The absence of which, Google pulls and shows the first few lines of content on SERPs. The description tag allows you to control what SE users see as a page summary before clicking. This helps in increasing your CTRs from Search.
The keyword meta usefulness is still inconclusive, but SEOers continue to use them. Avoid using more than 5-6 keywords in the tag per page to avoid Google from detecting and penalising due to any suspected keyword dumping.
Answer: The problem with keyword meta tags is they are a completely unreliable source of information for search engines. The temptation for people to alter search results in their favour with misleading keywords is just too great.
Answer: Those are two of the things that are used by search engines.  The exact weight of each changes frequently, they are generally regarded; however, as being fairly important.
One thing to note, care should be taken when entering values.  The more relevant the keywords and description are to the textual content of the site, the more weight may be given to them.  Of course there are no guarantees as nobody outside of the search engine companies really know what algorithms are being used.
This post talks a bit more about some aspects.


Magento2.3: How to send a file to another server?

Question:
I have a requirement that is sending the customer details like their
  wish-list details, address, names, etc., to another server(I have all
  the credentials for that server with me). I want to send that file via
  admin panel so that admin can send it by one click.
In order to do that, what are the things I have to do in Magento 2?
Could anyone please help me with this?
Your help will be greatly appreciated.
Answer:
Add button at backend customer view and create action that will
  connect to external server.
See how can one add button to customer view.
  How to add a button to the Customer Edit Page within the admin?
See how can we connect to server via code.
  https://www.php.net/manual/en/function.ftp-connect.php
If you want to do bulk operation then add new action at customer
  listing mass action. Read here how to do that
  https://webkul.com/blog/adding-custom-mass-action-in-admin-grid-in-magento-2/
You can easily get those customers ID to your action and retrieve
  information you want.
Establish connection to database and you're good to go.
Hope it will help you to get good start.
Comment: Thank you so much. I will try and get back you with comments.