Z-Transform Method for Pairwise Osteometric Pair-matching

A new pairwise osteometric pair-matching approach based on the Z-transform method is presented. In contrast to previous methods that perform a global t-test on the summed skeletal element pair measurement distances, this approach performs t-tests on each individual distance, facilitating the capture of measurement-specific variation. This new approach is compared to published pairwise sorting methods using a standard reference dataset of postcranial remains maintained by the Defense POW/MIA Accounting Agency. Receiver operating characteristic curve analysis indicates significantly improved performance for the clavicle and radius over all previous methods (p < 0.01). The z-transform method weighted by the effect size outperformed the t-test (Byrd and Adams) and the mean t-test (Lynch) for all elements (p < 0.01). The method performed better than the absolute value t-test (Lynch) for five elements (p < 0.01) and performed at least as well for the remainder. To facilitate usability all methods are available at: https://github.com/spawaskar-cora/z-transform-method.