Quantifying contingent relations from direct observation data: transitional probability comparisons versus Yule's Q

Measuring contingencies or sequential associations may be applied to a broad range of response-stimulus, stimulus-stimulus, or response-response relations. Within behavior analysis, response-stimulus contingencies have been quantified by comparing 2 transitional probabilities and plotting them in contingency space. Within and outside behavior analysis, Yule's Q has become a recommended statistic used to quantify sequential associations between 2 events. In the current paper, we identify 2 methods of transitional probability comparisons used in the behavior-analytic literature to estimate contingencies in natural settings. We compare each of these methods to the more established Yule's Q statistic and evaluate relations between each pair of indices. Advantages and disadvantages of each method are identified, with recommendations as to which approach may be most appropriate for measuring contingencies.