Applies to: StatTools 6.x and Up

How StatTools Computes Autocorrelation

StatTools calculates autocorrelation using the standard statistical formula for a lagged series, which differs slightly from a simple correlation of a manually lagged copy. For details, see:

• Correlation formula: NIST Correlation

• Autocorrelation formula: NIST Autocorrelation

Using Excel’s CORREL() on a lagged series will often give slightly different results because it doesn’t account for mean-centering and sample-size adjustments that StatTools applies.