PsiSpearmanRho (cell1, cell2)
PsiSpearmanRho returns a non-parametric measure (based on trial ranks). This function measures the correlation between two uncertain variables or functions, cell1 and cell2. This statistic can be used to determine how (if at all) the two uncertain variables or functions are correlated.
The Spearman correlation between two variables is equal to the Pearson correlation between the rank values of those two variables; while Pearson's correlation assesses linear relationships, Spearman's correlation assesses monotonic relationships (whether linear or not). If there are no repeated data values, a perfect Spearman correlation of +1 or −1 occurs when each of the variables is a perfect monotone function of the other.
The Spearman correlation between two variables will be high when observations have a similar rank between the two variables or functions, and low when observations have a dissimilar rank between the two variables or functions.