Inference and Explanation: Assessing the Likelihood of Conjunctive Events

Abstract

This study examined the effect of increasing the salience of alternatives in the use of inference and explanation sets when evaluating the likelihood of conjunctive events. Response mode (ranking or rating of events) was used to manipulate the salience of alternatives in a professional judgment context using a standard conjunction task. Participants were 196 experienced professionals and 192 undergraduate students. There was a significant interaction for attribution set x response mode. The different in conjunction effects between an inference and an explanation set was not observed when subjects were asked to rank events rather than to rate their likelihood. This finding provides evidence that a model of causal reasoning should include evaluating the strength of alternatives as well as the necessity and sufficiency of a possible cause.