Assessment of covariation by humans and animals: The joint influence of prior expectations and current situational information.

In this article, we propose a theoretical framework for understanding and integrating people's and animals' covariation assessment. We argue that covariation perception is determined by the interaction between two sources of information: (a) the organism's prior expectations about the covariation between two events and (b) current situational information provided by the environment about the objective contingency between the events. Both accuracies and errors in people's and animals' covariation assessments are analyzed within this interactional theoretical framework. We then review four lines of research in support of this analysis. Finally, we consider the issue of accuracy versus rationality in covariation assessment. A consensus has been forming among learning, clinical, and social psychologists: The ability to detect the relationships or covariations among stimuli, behaviors, and outcomes in one's environment is an important component of adaptive behavior. The covariation between two events may be defined in terms of their co-occurrence (i.e., the degree to which one event occurs more often in the presence than in the absence of the other event). Information about the relationships or covariations between events in the world provides people and animals with a means of explaining the past, controlling the present, and predicting the future, thereby maximizing the likelihood that they can obtain desired outcomes and avoid aversive ones. The concept of covariation provides a cornerstone for a number of substantive areas within psychology. For example, contemporary learning theorists point to the role of ob