An Improved Algorithm for Crossdating Tree-Ring Series

Abstract

The CROS algorithm for crossdating tree-ring series has proved useful. Because it uses Student's t to test correlations which are not independent between autocorrelated tree-ring series, it does not give a good measure of the relative significance of high correlations. It can be improved by transforming the correlation coefficients to normally distributed values, and giving a conservative estimate of the significance of the highest of these by a revised t, derived from its studentized deviation from the mean value. The improved algorithm should help any dendrochronologist who routinely dates oak timbers.