Starts by showing that semantic complexity is not as such a barrier to being a referring expression, using the example of compound names. Goes on to consider whether definite descriptions, at least in some uses, should be counted as referring expressions and concludes that they should be, even if one endorses Russellian truth conditions for sentences containing definite descriptions.

Definite referring expressions have been studied almost exclusively with respect to their ability to uniquely identify objects. Based on examples of NPs with the drawn from naturally occurring texts, I argue that definite referring expressions serve other functions, as well — they indicate the prominence of a referent, the referent's status as a role function or the viewpoint from which the referent is presented. All of this information contributes to the construction of discourse referents and is (...) therefore part of the speech act of referring. In general, speakers do not talk about objects in a neutral fashion, but rather attempt to induce addressees to accept them into the discourse under different guises. Thus, the notion of a successful reference cannot be restricted to cases in which an object is uniquely identified. (shrink)

This paper presents two cognitive models that simulate the production of referring expressions in the iMAP task—a task-oriented dialog. One general model is based on Dale and Reiter’s (1995)incremental algorithm, and the other is a simple template model that has a higher correlation with the data but is specifically geared toward the properties of the iMAP task. The property of the iMAP task environment that is modeled here is that the color feature is unreliable for identifying referents while (...) other features are reliable. The low computational cost of the incremental algorithm for generating referring expressions makes it an interesting starting point for a cognitive model. However, its explanatory power is limited, because it generates uniquely distinguishing referring expressions and because it considers features for inclusion in the referring expression in a fixed order. The first model extends the original incremental algorithm by an ability to adapt to feedback of whether a referring expression was used successfully, but it seems to overpredict the frequency with which distinguishing expressions are made and underpredict the frequency of overspecified referring expressions. The second model produces features for referring expressions purely based on its current estimate of a feature’s utility. Both models predict the observed human behavior of decreasing use of color terms and increasing use of useful feature terms. (shrink)

This is a book about the pragmatics of reference. When we communicate through language we inevitably talk about things. Those things might be people, places or objects, or they might be thoughts, ideas, emotions or abstract concepts. To talk about things, we need to refer to things, and this book is about how we refer to things.

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)

In referential communication, Grice's Maxim of Quantity is thought to imply that utterances conveying unnecessary information should incur comprehension difficulties. There is, however, considerable evidence that speakers frequently encode redundant information in their referring expressions, raising the question as to whether such overspecifications hinder listeners’ processing. Evidence from previous work is inconclusive, and mostly comes from offline studies. In this article, we present two event‐related potential (ERP) experiments, investigating the real‐time comprehension of referring expressions that contain (...) redundant adjectives in complex visual contexts. Our findings provide support for both Gricean and bounded‐rational accounts. We argue that these seemingly incompatible results can be reconciled if common ground is taken into account. We propose a bounded‐rational account of overspecification, according to which even redundant words can be beneficial to comprehension to the extent that they facilitate the reduction of listeners’ uncertainty regarding the target referent. (shrink)

The tradeoff hypothesis in the speech–gesture relationship claims that (a) when gesturing gets harder, speakers will rely relatively more on speech, and (b) when speaking gets harder, speakers will rely relatively more on gestures. We tested the second part of this hypothesis in an experimental collaborative referring paradigm where pairs of participants (directors and matchers) identified targets to each other from an array visible to both of them. We manipulated two factors known to affect the difficulty of speaking to (...) assess their effects on the gesture rate per 100 words. The first factor, codability, is the ease with which targets can be described. The second factor, repetition, is whether the targets are old or new (having been already described once or twice). We also manipulated a third factor, mutual visibility, because it is known to affect the rate and type of gesture produced. None of the manipulations systematically affected the gesture rate. Our data are thus mostly inconsistent with the tradeoff hypothesis. However, the gesture rate was sensitive to concurrent features of referring expressions, suggesting that gesture parallels aspects of speech. We argue that the redundancy between speech and gesture is communicatively motivated. (shrink)

Children often refer to things ambiguously but learn not to from responding to clarification requests. We review and explore this learning process here. In Study 1, eighty-four 2- and 4-year-olds were tested for their ability to request stickers from either (a) a small array with one dissimilar distracter or (b) a large array containing similar distracters. When children made ambiguous requests, they received either general feedback or specific questions about which of two options they wanted. With training, children learned to (...) produce more complex object descriptions and did so faster in the specific feedback condition. They also tended to provide more information when requesting stickers from large arrays. In Study 2, we varied only distracter similarity during training and then varied array size in a generalization test. Children found it harder to learn in this case. In the generalization test, 4-year-olds were more likely to provide information (a) when it was needed because distracters were similar to the target and (b) when the array size was greater (regardless of need for information). We discuss how clear cues to potential ambiguity are needed for children to learn to tailor their referring expression to context and how several cues of heuristic value (e.g., more distracters > say more) can promote the efficiency of communication while language is developing. Finally, we consider whether it would be worthwhile drawing on the human learning process when developing algorithms for the production of referring expressions. (shrink)

A substantial amount of recent work in natural language generation has focused on the generation of ‘‘one-shot’’ referring expressions whose only aim is to identify a target referent. Dale and Reiter's Incremental Algorithm (IA) is often thought to be the best algorithm for maximizing the similarity to referring expressions produced by people. We test this hypothesis by eliciting referring expressions from human subjects and computing the similarity between the expressions elicited and the ones (...) generated by algorithms. It turns out that the success of the IA depends substantially on the ‘‘preference order’’ (PO) employed by the IA, particularly in complex domains. While some POs cause the IA to produce referring expressions that are very similar to expressions produced by human subjects, others cause the IA to perform worse than its main competitors; moreover, it turns out to be difficult to predict the success of a PO on the basis of existing psycholinguistic findings or frequencies in corpora. We also examine the computational complexity of the algorithms in question and argue that there are no compelling reasons for preferring the IA over some of its main competitors on these grounds. We conclude that future research on the generation of referring expressions should explore alternatives to the IA, focusing on algorithms, inspired by the Greedy Algorithm, which do not work with a fixed PO. (shrink)

Human instructors often refer to objects and actions involved in a task description using both linguistic and non-linguistic means of communication. Hence, for robots to engage in natural human-robot interactions, we need to better understand the various relevant aspects of human multi-modal task descriptions. We analyse reference resolution to objects in a data collection comprising two object manipulation tasks and find that 78.76% of all referring expressions to the objects relevant in Task 1 are verbally underspecified and 88.64% (...) of all referring expressions are verbally underspecified in Task 2. The data strongly suggests that a language processing module for robots must be genuinely multi-modal, allowing for seamless integration of information transmitted in the verbal and the visual channel, whereby tracking the speaker’s eye gaze and gestures as well as object recognition are necessary preconditions. (shrink)

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)

A fundamental part of the process of referring to an entity is to categorise it (for instance, as the woman). Where multiple categorisations exist, this implicitly involves the adoption of a conceptual perspective. A challenge for the automatic Generation of Referring Expressions is to identify a set of referents coherently, adopting the same conceptual perspective. We describe and evaluate an algorithm to achieve this. The design of the algorithm is motivated by the results of psycholinguistic experiments.

Speakers’ perception of a visual scene influences the language they use to describe it—which objects they choose to mention and how they characterize the relationships between them. We show that visual complexity can either delay or facilitate description generation, depending on how much disambiguating information is required and how useful the scene's complexity can be in providing, for example, helpful landmarks. To do so, we measure speech onset times, eye gaze, and utterance content in a reference production experiment in which (...) the target object is either unique or non-unique in a visual scene of varying size and complexity. Speakers delay speech onset if the target object is non-unique and requires disambiguation, and we argue that this reflects the cost of deciding on a high-level strategy for describing it. The eye-tracking data demonstrate that these delays increase when speakers are able to conduct an extensive early visual search, implying that when speakers scan too little of the scene early on, they may decide to begin speaking before becoming aware that their description is underspecified. Speakers’ content choices reflect the visual makeup of the scene—the number of distractors present and the availability of useful landmarks. Our results highlight the complex role of visual perception in reference production, showing that speakers can make good use of complexity in ways that reflect their visual processing of the scene. (shrink)

The aim of this article is to investigate whether choosing the appropriate referring expression requires taking into account the hearer’s perspective, as is predicted under some versions of bidirectional Optimality Theory but is unexpected under other versions. We did this by comparing the results of 25 young and 25 elderly adults on an elicitation task based on eight different picture stories, and a comprehension task based on eight similar written stories. With respect to the elicitation task, we found that (...) elderly adults produce pronouns significantly more often than young adults when referring to the old topic in the presence of a new topic. With respect to the comprehension task, no significant differences were found between elderly and young adults. These results support the hypothesis that speakers optimize bidirectionally and take into account hearers when selecting a referring expression. If the use of a pronoun will lead to an unintended interpretation by the hearer, the speaker will use an unambiguous definite noun phrase instead. Because elderly adults are more limited in their processing capacities, as is indicated by their smaller working memory capacity, as speakers they will not always be able to reason about the hearer’s choices. As a result, they frequently produce non-recoverable pronouns. (shrink)

We report on two experiments investigating the effect of an increased cognitive load for speakers on the choice of referring expressions. Speakers produced story continuations to addressees, in which they referred to characters that were either salient or non-salient in the discourse. In Experiment 1, referents that were salient for the speaker were non-salient for the addressee, and vice versa. In Experiment 2, all discourse information was shared between speaker and addressee. Cognitive load was manipulated by the presence (...) or absence of a secondary task for the speaker. The results show that speakers under load are more likely to produce pronouns, at least when referring to less salient referents. We take this finding as evidence that speakers under load have more difficulties taking discourse salience into account, resulting in the use of expressions that are more economical for themselves. (shrink)

This book describes the repertoire and uses of referring expressions by French-speaking children and their interlocutors in naturally occurring dialogues at home and at school, in a wide-range of communicative situations and activities. Through the lens of an interactionist and dialogical perspective, it highlights the interaction between the formal aspects of the acquisition of grammatical morphemes, the discourse-pragmatic dimension, and socio-discursive, interactional and dialogical factors. Drawing on this multidimensional theoretical and methodological framework, the first part of the book (...) deals with the relation between reference and grammar, while the second part is devoted to the role of the communicative experience. Progressively, a set of arguments is brought out in favor of a dialogical and interactionist account of children's referential development. This theoretical stance is further discussed in relation to other approaches of reference acquisition. Thus, this volume provides researchers and students with new perspectives and methods for the study of referring expressions in children. (shrink)

The term 'referring expression' is often used without definition, and models of referring usually ignore the question of how NP's are recognized as referring expressions in discourse. In this paper, I review some relevant distinctions from the research in generics and, on that basis, provide a definition of referring expressions as specific and non-kind-referring noun phrases. I discuss some complications to the definition. Using Kronfeld's model of referring as my framework, I discuss (...) the interaction of the recognition of referring expressions and the recognition of relevant identification criteria. I propose that all present suggestions for identification constraints fall into three groups, and argue that the recognition of referring expressions always depends on the recognition of some identification constraints. On this basis, I extend the framework with procedural information. (shrink)

This paper presents a Conceptual Graph (CG) framework to the Generation of Referring Expressions (GRE). Employing Conceptual Graphs as the underlying formalism allows a rigorous, semantically rich, approach to GRE. A number of advantages over existing work are discussed. The new framework is also used to revisit existing complexity results in a fully rigorous way, showing that the expressive power of CGs does not increase the theoretical complexity of GRE.

Following Neale, I call the notion that there can be no such thing as a structured referring expression ‘structure skepticism’. The specific aim of this paper is to defuse some putative counterexamples to structure skepticism. The general aim is to bolster the case in favor of the thesis that lack of structure—in a sense to be made precise—is essential to reference.

In this paper we consider the potential role of metarepresentation—the representation of another representation, or as commonly considered within cognitive science, the mental representation of another individual's knowledge and beliefs—in mediating definite reference and common ground in conversation. Using dialogues from a referential communication study in which speakers conversed in succession with two different addressees, we highlight ways in which interlocutors work together to successfully refer to objects, and achieve shared conceptualizations. We briefly review accounts of how such shared conceptualizations (...) could be represented in memory, from simple associations between label and referent, to “triple co-presence” representations that track interlocutors in an episode of referring, to more elaborate metarepresentations that invoke theory of mind, mutual knowledge, or a model of a conversational partner. We consider how some forms of metarepresentation, once created and activated, could account for definite reference in conversation by appealing to ordinary processes in memory. We conclude that any representations that capture information about others' perspectives are likely to be relatively simple and subject to the same kinds of constraints on attention and memory that influence other kinds of cognitive representations. (shrink)

RESUMO Este artigo tem como objetivo ilustrar a contribuição do dialogismo para o campo de aquisição da linguagem. De acordo com as abordagens dialógicas, as crianças não experienciam unidades e estruturas linguísticas per se; elas experienciam a linguagem em contextos significativos. Mais especificamente, gêneros do discurso, atividades e situações de interação aparecem como mediadores entre o discurso individual, os usos sociais e uma linguagem particular. Para ilustrar as implicações de uma abordagem dialógica, este artigo apresenta uma pesquisa sobre a aquisição (...) de expressões referenciais (projeto DIAREF). As expressões referenciais são particularmente relevantes, já que seu domínio envolve tanto aspectos formais quanto funcionais da língua. Os resultados mostram que os usos de substantivos, pronomes pessoais, pronomes demonstrativos e deslocamentos realizados pelas crianças são determinados em conjunto com os fatores pragmático-discursivos, tais como a posição nos encadeamentos referenciais, e fatores sócio discursivos, tais como gêneros do discurso, atividades e situações interacionais. (shrink)

A fundamental part of the process of referring to an entity is to categorise it (for instance, as the woman). Where multiple categorisations exist, this implicitly involves the adoption of a conceptual perspective. A challenge for the automatic Generation of Referring Expressions is to identify a set of referents coherently, adopting the same conceptual perspective. We describe and evaluate an algorithm to achieve this. The design of the algorithm is motivated by the results of psycholinguistic experiments.

Word order variation in Mandarin Chinese results in two constructions consisting of a noun phrase, a cluster of a demonstrative and a classifier, and a relative clause : the OMN with the RC+DM+NP order and the IMN with DM+RC+NP order. This study used corpus data to show correlational patterns of constructional choices. Specifically, OMN is associated with new and inanimate NPs serving the grammatical role of object in the relative clause that serves the discourse function of identification. By contrast, for (...) IMN, the head NP tends to carry given information, tends to be an animate entity, tends to serve the grammatical role of subject in the relative clause, and tends to have an RC that serves the discourse function of characterization. We suggest that the usage patterns can be interpreted in terms of the cognitive and communicative principles of relevance. (shrink)

Psycholinguistic studies often look at the production of referring expressions in interactive settings, but so far few referring expression generation algorithms have been developed that are sensitive to earlier references in an interaction. Rather, such algorithms tend to rely on domain-dependent preferences for both content selection and linguistic realization. We present three experiments showing that humans may opt for dispreferred attributes and dispreferred modifier orderings when these were primed in a preceding interaction (without speakers being consciously aware (...) of this). In addition, we show that speakers are more likely to produce overspecified references, including dispreferred attributes (although minimal descriptions with preferred attributes would suffice), when these were similarly primed. (shrink)

Theoretical accounts of negative expressives such as damn have ascribed two main properties to this type of adjective, namely that they are typically speaker-oriented, and that they can be flexible with regard to their syntactic attachment. However, it is not clear what this means during online sentence processing. For example, is it effortful for comprehenders to derive the speaker's negative attitude conveyed by an expressive adjective, or is it a rapid, automatic process? And do comprehenders understand the speaker's attitude regardless (...) of the expressive's syntactic position? The current work provides the first evidence supporting theoretical claims by investigating the incremental processing of Italian negative expressive adjectives. In an eye-tracking study, we show that expressive content is rapidly integrated with information about the speaker's attitude, resulting in the anticipation of an upcoming referent, regardless of the expressive's syntactic realization. We argue that comprehenders use expressives as an ostensive cue that allows for automatic retrieval of the speaker's negative attitude. (shrink)

Two eye-tracking experiments investigated how and when pointing gestures and location descriptions affect target identification. The experiments investigated the effect of gestures and referring expressions on the time course of fixations to the target, using videos of human gestures and human voice, and animated gestures and synthesized speech. Ambiguous, yet informative pointing gestures elicited attention and facilitated target identification, akin to verbal location descriptions. Moreover, target identification was superior when both pointing gestures and verbal location descriptions were used. (...) These findings suggest that gesture not only operates as a context to verbal descriptions, or that verbal descriptions operate as a context to gesture, but that they complement one another in reference resolution. (shrink)

Whether a predicate is a referential expression depends upon what reference is conceived to be. Even if it is granted that reference is a relation between words and worldly items, the referents of expressions being the items to which they are so related, this still leaves considerable scope for disagreement about whether predicates refer. One of Frege's great contributions to the philosophy of language was to introduce an especially liberal conception of reference relative to which it is unproblematic to (...) suppose that predicates are referring expressions. According to this liberal conception, each significant expression in a language has its own distinctive semantic role or power, a power to effect the truth-value of the sentences in which it occurs. (shrink)

Putnam’s model-theoretic arguments for the indeterminacy of reference have been taken to pose a special problem for mathematical languages. In this paper, I argue that if one accepts that there are theory-external constraints on the reference of at least some expressions of ordinary language, then Putnam’s model-theoretic arguments for mathematical languages don’t go through. In particular, I argue for a kind of descriptivism about mathematical expressions according to which their reference is “anchored” in the reference of expressions (...) of ordinary language. These anchors add enough to the content of mathematical expressions to forestall the radical kind of indeterminacy that model-theoretic arguments are purported to show, while still leaving room for a plausible, moderate kind of indeterminacy. (shrink)

It has often been observed that color is a highly preferred attribute for use in distinguishing descriptions, that is, referring expressions produced with the purpose of identifying an object within a visual scene. However, most of these observations were based on visual displays containing only colors that were maximally different in hue and for which the language of experimentation possessed basic color terms. The experiments described in this paper investigate whether speakers’ preference for color is reduced if the (...) color of the target referent is similar to that of the distractors. Because colors that look similar are often also harder to distinguish linguistically, we also examine the impact of the codability of color values. As a third factor, we investigate the salience of available alternative attributes and its impact on the use of color. The results of our experiments show that, while speakers are indeed less likely to use color when the colors in a display are similar, this effect is mostly due to the difficulty in naming similar colors. Color use for color with a basic color term is affected only when the colors of target and distractors are very similar (yet still distinguishable). The salience of our alternative attribute size, manipulated by varying the difference in size between target and distractors, had no impact on the use of color. (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)

This paper provides a new solution to the concept horse paradox. Frege argued no name co-refers with a predicate because no name can be inter-substituted with a predicate. This led Frege to embrace the paradox of the concept horse. But Frege got it wrong because predicates are impurely referring expressions and we shouldn’t expect impurely referring expressions to be intersubstitutable even if they co-refer, because the contexts in which they occur are sensitive to the extra information (...) they carry about their referents. (shrink)

While speakers have been shown to adapt to the knowledge state of their addressee in choosing referring expressions, they often also show some egocentric tendencies. The current paper aims to provide an explanation for this “mixed” behavior by presenting a model that derives such patterns from the probabilistic combination of both the speaker's and the addressee's perspectives. To test our model, we conducted a language production experiment, in which participants had to refer to objects in a context that (...) also included a visually misleading object whose function was either known to both partners, or known just to the speaker but not the addressee. Modeling results indicate that the experimental findings cannot be explained by assuming that speakers tailor a referring expression solely to their own perspective or to the perspective of their addressee. Instead, accounting for the behavioral pattern requires an approach where both perspectives influence the choice of referring expressions. Nevertheless, in our situation, speakers consider their partner's perspective more than their own. (shrink)

It has often been observed that color is a highly preferred attribute for use in distinguishing descriptions, that is, referring expressions produced with the purpose of identifying an object within a visual scene. However, most of these observations were based on visual displays containing only colors that were maximally different in hue and for which the language of experimentation possessed basic color terms. The experiments described in this paper investigate whether speakers’ preference for color is reduced if the (...) color of the target referent is similar to that of the distractors. Because colors that look similar are often also harder to distinguish linguistically, we also examine the impact of the codability of color values. As a third factor, we investigate the salience of available alternative attributes and its impact on the use of color. The results of our experiments show that, while speakers are indeed less likely to use color when the colors in a display are similar, this effect is mostly due to the difficulty in naming similar colors. Color use for color with a basic color term is affected only when the colors of target and distractors are very similar. The salience of our alternative attribute size, manipulated by varying the difference in size between target and distractors, had no impact on the use of color. (shrink)

Whether a predicate is a referential expression depends upon what reference is conceived to be. Even if it is granted that reference is a relation between words and worldly items, the referents of expressions being the items to which they are so related, this still leaves considerable scope for disagreement about whether predicates refer. One of Frege's great contributions to the philosophy of language was to introduce an especially liberal conception of reference relative to which it is unproblematic to (...) suppose that predicates are referring expressions. According to this liberal conception, each significant expression in a language has its own distinctive semantic role or power, a power to effect the truth-value of the sentences in which it occurs. (shrink)