We examine the problem of generating definite noun phrases that are appropriate referring expressions; that is, noun phrases that (a) successfully identify the intended referent to the hearer whilst (b) not conveying to him or her any false conversational implicatures (Grice, 1975). We review several possible computational interpretations of the conversational implicature maxims, with different computational costs, and argue that the simplest may be the best, because it seems to be closest to what human speakers do. We describe our recommended (...) algorithm in detail, along with a specification of the resources a host system must provide in order to make use of the algorithm, and an implementation used in the natural language generation component of the IDAS system. (shrink)

This article introduces the topic ‘‘Production of Referring Expressions: Bridging the Gap between Computational and Empirical Approaches to Reference’’ of the journal Topics in Cognitive Science. We argue that computational and psycholinguistic approaches to reference production can benefit from closer interaction, and that this is likely to result in the construction of algorithms that differ markedly from the ones currently known in the computational literature. We focus particularly on determinism, the feature of existing algorithms that is perhaps most clearly at (...) odds with psycholinguistic results, discussing how future algorithms might include non-determinism, and how new psycholinguistic experiments could inform the development of such algorithms. (shrink)

Grice's notion of conversational implicature requires that speaker meaning be calculable on the basis of sentence meaning, and presumptions about the speaker's adherence to cooperative principles of conversation and the ability of the hearer to work out the speaker's meaning. However, the actual real‐time consideration of cooperative principles by both the hearer and speaker runs up against severe temporal constraints during language processing. This article considers the role of language processing research in the shaping of a theory of implicature, and (...) provides an empirical overview of pertinent current work in real‐time language production and comprehension. (shrink)

We investigated the coupling between a speaker's and a listener's eye movements. Some participants talked extemporaneously about a television show whose cast members they were viewing on a screen in front of them. Later, other participants listened to these monologues while viewing the same screen. Eye movements were recorded for all speakers and listeners. According to cross-recurrence analysis, a listener's eye movements most closely matched a speaker's eye movements at a delay of 2 sec. Indeed, the more closely a listener's (...) eye movements were coupled with a speaker's, the better the listener did on a comprehension test. In a second experiment, low-level visual cues were used to manipulate the listeners' eye movements, and these, in turn, influenced their latencies to comprehension questions. Just as eye movements reflect the mental state of an individual, the coupling between a speaker's and a listener's eye movements reflects the success of their communication. (shrink)

This study investigates to what extent the amount of variation in a visual scene causes speakers to mention the attribute color in their definite target descriptions, focusing on scenes in which this attribute is not needed for identification of the target. The results of our three experiments show that speakers are more likely to redundantly include a color attribute when the scene variation is high as compared with when this variation is low (even if this leads to overspecified descriptions). We (...) argue that these findings are problematic for existing algorithms that aim to automatically generate psychologically realistic target descriptions, such as the Incremental Algorithm, as these algorithms make use of a fixed preference order per domain and do not take visual scene variation into account. (shrink)

The notion of common ground is important for the production of referring expressions: In order for a referring expression to be felicitous, it has to be based on shared information. But determining what information is shared and what information is privileged may require gathering information from multiple sources, and constantly coordinating and updating them, which might be computationally too intensive to affect the earliest moments of production. Previous work has found that speakers produce overinformative referring expressions, which include privileged names, (...) violating Grice’s Maxims, and concluded that this is because they do not mark the distinction between shared and privileged information. We demonstrate that speakers are in fact quite effective in marking this distinction in the form of their utterances. Nonetheless, under certain circumstances, speakers choose to overspecify privileged names. (shrink)

In order to investigate whether addressees can make immediate use of speaker‐based constraints during reference resolution, participant addressees' eye movements were monitored as they helped a confederate cook follow a recipe. Objects were located in the helper's area, which the cook could not reach, and the cook's area, which both could reach. Critical referring expressions matched one object (helper's area) or two objects (helper's and cook's areas), and were produced when the cook's hands were empty or full, which defined the (...) cook's reaching ability constraints. Helper's first and total fixations showed that they restricted their domain of interpretation to their own objects when the cook's hands were empty, and widened it to include the cook's objects only when the cook's hands were full. These results demonstrate that addressees can quickly take into account task‐relevant constraints to restrict their referential domain to referents that are plausible given the speaker's goals and constraints. (shrink)

Utterances can convey more information than they explicitly encode, and speakers exploit communicative conventions in order to say more with less. However, the burden this places on perceivers is not well understood. This chapter examines the effect of speaker-specific information on pragmatic inferences using data from an experiment which investigated the time course of the use of pragmatic information in language comprehension. Previous evidence suggests that comprehenders who encounter a referential form, including a modifier that commonly indicates contrastiveness, assume that (...) the referential form is being used contrastively. Thus, they consequently look to the relevant object in the scene very early when processing the referential expression. In this case, people appear to be implicitly following H. P. Grice’s maxim of quantity. This chapter demonstrates that comprehenders stop using contrastive information early in resolving reference when speakers consistently do not use contrastive elements appropriately, consistent with a pragmatic explanation of referential contrast effects. (shrink)

This article offers a survey of computational research on referring expressions generation (REG). It introduces the REG problem and describes early work in this area, discussing what basic assumptions lie behind it, and showing how its remit has widened in recent years. We discuss computational frameworks underlying REG, and demonstrate a recent trend that seeks to link up REG algorithms with well-established Knowledge Representation traditions. Considerable attention is given to recent efforts at evaluating REG algorithms and the lessons that they (...) allow us to learn. The article concludes with a discussion of the way forward in REG, focussing on references in larger and more realistic settings. (shrink)