Tourtouri, Elli; Delogu, Francesca; Crocker, Matthew W.

Overspecification and uniform reduction of visual entropy facilitate referential processing

XPrag2017, Cologne, Germany, 2017.

Over-specifications (OS) are expressions that provide more information than minimally required for the identification of a referent, thereby violating Grice’s 2nd Quantity Maxim [1]. In Figure 1, for example, the expression “Find the blue ball” identifies exactly one object in all panels, but only in the top displays is the adjective required to disambiguate the target. In recent years, psycholinguistic research has tried to test the empirical validity of Grice’s Maxim, resulting in conflicting findings. That is, there is evidence both that OS hinders [2,3] and that it facilitates [4,5] referential processing. The current study investigates the influence of OS on visually-situated processing, when the context allows both a minimally-specified (MS) and an OS interpretation of pre-nominal adjectives (cf. Fig.1). Additionally, as the utterance unfolds over time, incoming words incrementally restrict the search space. In this sense, information on “blue” and “ball” is determined not only by their probability to occur in this context, but also by the amount of uncertainty about the target they reduce — in information theoretic terms [6]. A greater reduction of the referential set size on the adjective (A&C) results in a more uniform reduction profile (Uniform Reduction, UR), as the adjective reduces entropy by 1.58 bits and the noun by 1 bit. On the other hand, a moderate reduction of the set size on the adjective (B&D) results in a less uniform reduction profile (Nonuniform Reduction, NR): the adjective reduces entropy by .58 bits and the noun by 2 bits. This study examines whether, above and beyond any effects of specificity, the rate at which incoming words reduce visual entropy also affects referential processing.