Correlation of miRNA fluctuation with mean fluctuation. Each point represents a single sample in the study. The x-value of the point is the difference of the sample mean from the overall mean and the y-value is the difference between the expression of an miRNA in that sample and the mean expression of that miRNA across all samples. The slope of the line quantifies the sensitivity of fluctuations in the miRNA's value to fluctuations in the overall mean. This plot is presented as an example for a single microRNA; all miRNAs were plotted in this fashion.