Rating causal relations: Role of probability in judgments of response-outcome contingency.

Investigated the possible role of the conditional probabilities of an outcome given a response P(O/R) and of an outcome given the absence of a response P(O/NoR) in mediating college students' judgments of response–outcome contingency. A total of 150 Ss in 3 experiments were asked to describe the effect that telegraph key tapping had on the brief illumination of a lamp. Ss' ratings along a prevent–cause scale closely approximated the scheduled contingencies between response (R?=?key tapping) and outcome (O?=?lamp illumination), as measured by the delta coefficient δP?=?P(O/R)?–?P(O/NoR) (Exps 1 and 3). Ss also sensitively rated the conditional probabilities of an outcome when they tapped the key and when they refrained from doing so (Exps 2 and 3). Nevertheless, the evidence failed to support the hypothesis that causal ratings were mediated by subjective judgments of P(O/R) and P(O/NoR) because the errors made in judging the conditional probabilities were not consistent with the errors made judging δP. The authors suggest that an associative explanation derived from a model devised by R. A. Rescorla and A. R. Wagner (1972) might account for these and other results. (PsycINFO Database Record (c) 2010 APA, all rights reserved)