Z-Scores and Pearson Correlation: If we have scores that are expressed as standardized scores -- Z-Scores with a mean of zero and a variance of one -- then the formula for the Pearson Correlation becomes particularly simple.
PNG Formats. .PNG files in logo design and when you should use them. PNG is an acronym for Portable Network Graphics. PNGs are bitmpapped (raster/pixel based) image formats that can be used instead of GIF images or JPGs. PNG logo images are superior to other pixel based formats as they employ a âlosslessâ data compression system.
PNG. PNG, which can be pronounced ping or P-N-G, is a compressed raster graphic format. It is commonly used on the Web and is also a popular choice for application graphics. The PNG format was introduced in 1994, after the GIF and JPEG formats had already been around for several years.