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 format is a lossless compression file format, which makes it a common choice for use on the Web. PNG is a good choice for storing line drawings, text, and iconic graphics at a small file size. JPG format is a lossy compressed file format. This makes it useful for storing photographs at a smaller size than a BMP. JPG is a common choice for use on the Web because it is compressed. For storing line drawings, text, and iconic graphics at a smaller file size, GIF or PNG are better choices because they are lossless. JPEGs are for photographs and realistic images. PNGs are for line art, text-heavy images, and images with few colors.