Overextension of conjunctive concepts: Evidence for a unitary model of concept typicality and class inclusion.

Four experiments investigated how people judge both the typicality and membership of items in conjunctive concepts such as school furniture or sports which are games. Judgments of membership in conjunctions were overextended, and there was asymmetry between the constituent concepts in their influence on relative conjunctive concept membership. The results are discussed in the light of recent theoretical disputes about the modeling of concept representations and the process of forming