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(Portable Network Graphics) file format is regarded, and was made, as the free and open-source successor to the GIF file format. The PNG file format supports true color(16 million colors) whereas the GIF file format only allows 256 colors. PNG excels when the image has large areas of uniform color.