**Business / Finance / Correlation:** Reverse movement, usually downward, in the price of an individual stock, bond, commodity, or index. If prices have been rising on the market as a whole, and then fall dramatically, this is know as a correction within an upward trend. Antithesis of a technical rally. See: Dip, break.

Science / Spiders / Autocorrelation Function (ACF): the cross-correlation function of an image with itself. The ACF is centrosymmetric, and its highest peak is always in the origin, a shift position where both signal and noise contents of the image ove MORE

Business / Finance / Autocorrelation: The correlation of a variable with itself over successive time intervals. Sometimes called serial correlation. MORE

Science / Spiders / Fourier Shell Correlation (FSC): same as Fourier ring correlation, except that values of the discrete Fourier transforms are compared within corresponding shells, instead of rings [van Heel, 1987b. MORE

Business / Finance / Correlation Coefficient: Statistical measure of the degree to which the movements of two variables (stock/option/convertible prices or returns) are related. See: Correlation coefficient. MORE

Science / Spiders / Fourier Ring Correlation (FRC): a measure of statistical dependency between two averages, computed by comparison of rings in Fourier space [Saxton and Baumeister, 1982]. As the Differential Phase Residual, the FRC is used to establi MORE

Science / Marine Biology / Spatial Autocorrelation: A situation in which some parameter at any location (e.g., population density) can be predicted through a knowledge of the values of the parameter in other locations MORE