Covariation-based attribution: On the ability to assess multiple covariates of an effect

For logical and normative reasons, attributions have to follow, the covaria tion rule. However, little is known about the cognitive process by which th e covariation of an effect with multiple causes is extracted from empirical observations. Previous research used verbal quantifiers to manipulate cova riation with subjects (consensus), objects (distinctiveness), and time (con sistency). In contrast, the inductive assessment of covariation from a sequ ence of observations was the focus of the present experiments. Empirical fi ndings demonstrate that accurate covariation judgment is usually confined t o one focused factor. The role of the focal factor is augmented rather than discounted when another covarying factor is presents. When attributers can actively search for information, memory for singular observations is stron g, but attributional judgments deteriorate. Experimental search strategies improve event memory but interfere with covariation-based judgments. A unid imensional joint scale model provides a better account of underlying cognit ive processes than the common factorial-design model.