A Concordance Based Comparison of Dow Jones Industrial Average Charts

Analysis of concordance between distinct segments of DJIA history were performed using Kendall´s Tau, Spearman´s Rho, and Gini´s Mean Difference. In response to published concerns regarding similarities between 2013/14 and historical DJIA behaviors, specific concordance cross-comparisons were performed between the period leading into February 2014 and periods involving market crashes, as well as between lead-up periods to selected crashes, plus selected alternative periods, and all historical DJIA behavior. The conclusion drawn is that the periods leading up to the extreme market events of 1929 and 1987 crashes are not best-fits for behavior leading up to February 2014, nor with each other. Analysis of selected base periods using the selected metrics versus all other periods reveals good statistical matches are readily obtained for each (when extreme events themselves are excluded), as well as statistically better matches for crash lead-in periods and the period up to February 2014.