Predicting conjunction typicalities by component typicalities

Abstract

In two studies, we investigated to what extent typicalities in conjunctive concepts phrased as relative clauses-such as pets that are also birds-ean be predicted from simple functions of constituent typicalities and from extensions of such functions. In a first study, analyses of a large aggregated data set, based on seven different experiments, showed that a calibrated minimum rule model and some extensions of this model accounted for a very large part of the variance in the conjunction typicalities. The same models can also account for the so-called guppy effect. A psychological explanation is presented, which states that typicalitiesin contrast categories, likepets that are not birds and birds that are not pets, further improve the prediction of conjunction typicalities. This hypothesis is tested in a second study.One of the central questions about conceptual combinations is what happens to constituent concepts that are combined into a complex concept. Different types ofconceptual combinations have been distinguished: adjectivenoun combinations, such as sour wine (see, e.g., Murphy, 1988;Smith & Osherson, 1984;Smith, Osherson, Rips, & Keane, 1988), noun-noun combinations, such as pocket knife (Wisniewski, 1997;Wisniewski & Gentner, 1991), and relative clause descriptions, such as pets that are also birds (Hampton, 1987(Hampton, , 1988Storms, De Boeck, Van Mechelen, & Geeraerts, 1993;Storms, Van Mechelen, & De Boeck, 1994). In adjective-noun and nounnoun combinations, a considerable ambiguity may be present, in that a variety of relations can be implied. Ocean boat, ocean drive, and ocean book, for instance, all activate different relations between the head noun and the modifier ofthe compound (Murphy, 1988;Wisniewski, 1997). Relative clause descriptions of the form XS that are also YS differ from noun-noun and adjective-noun combinations in that this sort of conceptual combination implies a clear type of relation between the complex concept and its constituents-namely, a which are also relation.

The instantiation principle re-evaluated

“…The empirically obtained values, though, come from typicality ratings on a scale with a fixed range (from 1 to 10). It is quite likely that subjects in a rating task attempt to distribute their ratings as much as possible, thereby using the whole range of the scale (see, e.g., Jones, 1982;Storms, De Boeck, Hampton, & Van Mechelen, 1999). As a consequence, the decreasing correlations for increasing numbers of instantiated exemplars might be an artefact due to restriction of range.…”

The Role of Contrast Categories in Natural Language Concepts

“…However, information about related categories may be important as well in making category-related decisions (Goldstone, 1996;Storms, De Boeck, Hampton, & Van Mechelen, 1999). Categories that are believed to play a role in a concept's representation are called contrast categories.…”

Quantum structure in cognition

“…Hampton identified a guppy-like effect for the membership weights of items with respect to pairs of concepts and their conjunction (Hampton, 1988a), and equally so for the membership weights of items with respect to pairs of concepts and their disjunction (Hampton, 1988b). Many experiments and analyses of effects due to combining concepts in general have since been conducted (Hampton, 1987(Hampton, , 1988a(Hampton, ,b, 1991(Hampton, , 1996(Hampton, , 1997aOsherson & Smith, 1981Rips, 1995;Smith & Osherson, 1984;Smith, Osherson, Rips & Keane, 1988;Springer & Murphy, 1992;Storms, De Boeck, Van Mechelen & Geeraerts, 1993;Storms, De Boeck, Hampton & van Mechelen, 1999). However, none of the currently existing concept theories provides a satisfactory description and/or explanation of such effect for concept combinations.…”