Memory and cognition applied.

UNLABELLED: Gibbs and Moise [Gibbs, R., Moise, J., 1997. Pragmatics in understanding what is said. Cognition 62, 51-74], present experimental results which, they claim, show that people recognize a distinction between what is said and what is implicated. They also claim that these results provide support for theories of utterance interpretation (such as RELEVANCE Theory) which recognize that pragmatic processes are involved not only in understanding what is implicated but also in working out what is said (the 'explicature'). We attempted to replicate some of these experiments and also adapted them. Our results fail to confirm Gibbs and Moise's claims. Most significantly, they show that, under certain conditions, subjects select implicatures when asked to select the paraphrase that best reflects what a speaker has said. We suggest that our results can be explained within the framework of RELEVANCE Theory (Sperber, D., Wilson, D., 1986. RELEVANCE: Communication and Cognition. Blackwell, Oxford) if we assume that subjects select the paraphrase that comes closest to achieving the same set of communicated contextual effects as the original utterance. When an utterance gives rise to a single strong implicature, subjects tend to select this as the paraphrase that best reflects what is said; in other cases (for example in Gibbs and Moise's stimuli) subjects tend to select the explicature.

Cognition↗

PubMed1999

Subjective probability of disjunctive hypotheses: local-weight models for decomposition of evidential support.

When the probability of a single member of a set of mutually exclusive and exhaustive possibilities is judged, its alternatives are evaluated as a composite "residual" hypothesis. Support theory (Rottenstreich & Tversky, 1997; Tversky & Koehler, 1994) implies that the process of packing alternatives together in the residual reduces the perceived evidential support for the set of alternatives and consequently inflates the judged probability of the focal hypothesis. Previous work has investigated the global weights that determine the extent to which the overall evidential support for the alternatives is discounted by this packing operation (Koehler, Brenner, & Tversky, 1997). In the present investigation, we analyze this issue in greater detail, examining the local weights that measure the specific contribution of each component hypothesis included implicitly in the residual. We describe a procedure for estimating local weights and introduce a set of plausible properties that impose systematic ordinal relationships among local weights. Results from four experiments testing these properties are reported, and a local-weight model is developed that accounts for nearly all of the variance in the probability judgments in these empirical tests. Local weights appear to be sensitive both to the individual component with which they are associated and to the residual hypothesis in which the component resides.

Cognition↗