Situational information contributes to object categorization and inference.

Three experiments demonstrated that situational information contributes to the categorization of functional object categories, as well as to inferences about these categories. When an object was presented in the context of setting and event information, categorization was more accurate than when the object was presented in isolation. Inferences about the object similarly became more accurate as the amount of situational information present during categorization increased. The benefits of situational information were higher when both setting and event information were available than when only setting information was available. These findings indicate that situational information about settings and events is stored with functional object categories in memory. Categorization and inference become increasingly accurate as the information available during categorization matches situational information stored with the category.

Assessing the causal structure of function.

Theories typically emphasize affordances or intentions as the primary determinant of an object's perceived function. The HIPE theory assumes that people integrate both into causal models that produce functional attributions. In these models, an object's physical structure and an agent's action specify an affordance jointly, constituting the immediate causes of a perceived function. The object's design history and an agent's goal in using it constitute distant causes. When specified fully, the immediate causes are sufficient for determining the perceived function--distant causes have no effect (the causal proximity principle). When the immediate causes are ambiguous or unknown, distant causes produce inferences about the immediate causes, thereby affecting functional attributions indirectly (the causal updating principle). Seven experiments supported HIPE's predictions.