Human communication is often thought about in terms of transmitted messages in a conventional code like a language. But communication requires a specialized interactive intelligence. Senders have to be able to perform recipient design, while receivers need to be able to do intention recognition, knowing that recipient design has taken place. To study this interactive intelligence in the lab, we developed a new task that taps directly into the underlying abilities to communicate in the absence of a conventional code. We (...) show that subjects are remarkably successful communicators under these conditions, especially when senders get feedback from receivers. Signaling is accomplished by the manner in which an instrumental action is performed, such that instrumentally dysfunctional components of an action are used to convey communicative intentions. The findings have important implications for the nature of the human communicative infrastructure, and the task opens up a line of experimentation on human communication. (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)

To what extent is the choice of what to say driven by seemingly irrelevant cues in the visual world being described? Among such cues, how does prior description affect how we process spatial scenes? When people describe where objects are located their use of spatial language is often associated with a choice of reference frame. Two experiments employing between-participants designs (N = 490) examined the effects of visual cueing and previous description on reference frame choice as reflected in spatial prepositions (...) (in front of, to the left of, etc.) to describe pictures of object pairs. Experiment 1 examined the effects of visual and linguistic cues on spatial description choice through movement of object(s) in spatial scenes, showing sizeable effects of visual cueing on reference frame choice. Experiment 2 monitored eye movements of participants following a linguistic example description, revealing two findings: eye movement “signatures” associated with distinct reference frames as expressed in language, and transfer of these eye movement patterns just prior to spatial description for different (later) picture descriptions. Both verbal description and visual cueing similarly influence language production choice through manipulation of visual attention, suggesting a unified theory of constraints affecting spatial language choice. (shrink)

We take up issues raised in the commentaries about our proposal that social robots are depictions of social agents. Among these issues are the realism of social agents, experiencing robots, communicating with robots, anthropomorphism, and attributing traits to robots. We end with comments about the future of social robots.

For people to contribute to discourse, they must do more than utter the right sentence at the right time. The basic requirement is that they add to their common ground in an orderly way. To do this, we argue, they try to establish for each utterance the mutual belief that the addressees have understood what the speaker meant well enough for current purposes. This is accomplished by the collective actions of the current contributor and his or her partners, and these (...) result in units of conversation called contributions. We present a model of contributions and show how it accounts for a variety of features of everyday conversations. (shrink)

Clark highlights a neglected issue in research on language use: the process by which speakers and addressees anchor utterances with respect to individual entities in their common ground. In his review, he identifies the challenges linked to investigations of anchoring, but also displays the pitfalls of evading it.

Coordination between speakers in dialogue requires balancing repetition and change, the old and the new. Interlocutors tend to reuse established forms, relying on communicative precedents. Yet linguistic interaction also necessitates adaptation to changing contexts or dynamic tasks, which might favor abandoning existing precedents in favor of better communicative alternatives. We explored this tension using a maze game task in which individual participants and interacting pairs had to describe figures and their positions in one of two possible maze types: a regular (...) maze, in which the grid‐like structure of the maze is highlighted, and an irregular maze, in which specific parts of the maze are salient. Participants repeated this task several times. Both individuals and interacting pairs were affected by the different maze layouts, initially using more idiosyncratic description schemes for irregular mazes and more systematic schemes for regular mazes. Interacting pairs, but not individuals, abandoned their unsystematic initial descriptions in favor of a more systematic approach, which was better adapted for repeated interaction. Our results show communicative conventions are initially shaped by context, but interaction opens up the possibility for change if better alternatives are available. (shrink)

Communication involves a great deal of uncertainty. Prima facie, it is therefore surprising that biological communication systems—from cellular to human—exhibit a high degree of ambiguity and often leave its resolution to contextual cues. This puzzle deepens once we consider that contextual information may diverge between individuals. In the following we lay out a model of ambiguous communication in iterated interactions between subjectively rational agents lacking a common contextual prior. We argue ambiguity’s justification to lie in endowing interlocutors with means to (...) flexibly adapt language use to each other and the context of their interaction to serve their communicative preferences. Linguistic alignment is shown to play an important role in this process; it foments convergence of contextual expectations and thereby leads to agreeing use and interpretation of ambiguous messages. We conclude that ambiguity is ecologically rational when interlocutors’ contextual expectations are generally in line or they interact multiple times in an informative context, enabling for the alignment of their expectations. In light of these results meaning multiplicity can be understood as an opportunistic outcome enabled and shaped by linguistic adaptation and contextual information. 1Meaning Multiplicity in Communication 2Ambiguous Signalling through Pragmatic Inference 2.1Preliminaries 2.2Signalling behaviour 2.3Communicative success 2.4Iterated interactions 3Predictions for Single and Iterated Interactions 3.1Simulations 3.2Exploration and past experience 3.3Preemptive adaptation 4Discussion 5Conclusion Appendix. (shrink)

Communication involves a great deal of uncertainty. Prima facie, it is therefore surprising that biological communication systems—from cellular to human—exhibit a high degree of ambiguity and often leave its resolution to contextual cues. This puzzle deepens once we consider that contextual information may diverge between individuals. In the following we lay out a model of ambiguous communication in iterated interactions between subjectively rational agents lacking a common contextual prior. We argue ambiguity’s justification to lie in endowing interlocutors with means to (...) flexibly adapt language use to each other and the context of their interaction to serve their communicative preferences. Linguistic alignment is shown to play an important role in this process; it foments convergence of contextual expectations and thereby leads to agreeing use and interpretation of ambiguous messages. We conclude that ambiguity is ecologically rational when interlocutors’ contextual expectations are generally in line or they interact multiple times in an informative context, enabling for the alignment of their expectations. In light of these results meaning multiplicity can be understood as an opportunistic outcome enabled and shaped by linguistic adaptation and contextual information. (shrink)

Written memoranda of conversations, or memcons, provide a near‐contemporaneous record of what was said in conversation, and offer important insights into the activities of high‐profile individuals. We assess the impact of writing a memcon on memory for conversation. Pairs of participants engaged in conversation and were asked to recall the contents of that conversation 1 week later. One participant in each pair memorialized the content of the interaction in a memcon shortly after the conversation. Participants who generated memcons recalled more (...) details of the conversations than participants who did not, but the content of recall was equally and largely accurate for both participants. Remarkably, only 4.7% of the details of the conversation were recalled by both of the partners after a week delay. Contemporaneous note‐taking appears to enhance memory for conversation by increasing the amount of information remembered but not the accuracy of that information. These findings have implications for evaluating the testimony of participants on conversations with major political or legal ramifications. (shrink)

During communication, we form assumptions about what our communication partners know and believe. Information that is mutually known between the discourse partners—their common ground—serves as a backdrop for successful communication. Here we present an introduction to the focus of this topic, which is the role of memory in common ground and language use. Two types of questions emerge as central to understanding the relationship between memory and common ground, specifically questions having to do with the representation of common ground in (...) memory, and the use of common ground during language processing. (shrink)

No one denies that people adapt what they say and how they interpret what is said to them, depending on their interactive partners. What is controversial is when and how they do so. Several psycholinguistics research programs have found what appear to be failures to adapt to partners in the early moments of processing and have used this evidence to argue for modularity in the language processing architecture, claiming that the system cannot take into account a partner’s distinct needs or (...) knowledge early in processing. We review the evidence for both early and delayed partner‐specific adaptations, and we identify some challenges and difficulties with interpreting this evidence. We then discuss new analyses from a previously published referential communication experiment (Metzing & Brennan, 2003) demonstrating that partner‐specific effects need not occur late in processing. In contrast to Pickering and Garrod (2004) and Keysar, Barr, and Horton (1998b), we conclude that there is no good evidence that early processing has to be be “egocentric,”“dumb,” or encapsulated from social knowledge or common ground, but that under some circumstances, such as when one partner has made an attribution about another’s knowledge or needs, processing can be nimble enough to adapt quite early to a perspective different from one’s own. (shrink)

The nature of complex concepts has important implications for the computational modelling of the mind, as well as for the cognitive science of concepts. This paper outlines the way in which RVC – a Relational View of Concepts – accommodates a range of complex concepts, cases which have been argued to be non-compositional. RVC attempts to integrate a number of psychological, linguistic and psycholinguistic considerations with the situation-theoretic view that information-carrying relations hold only relative to background situations. The central tenet (...) of RVC is that the content of concepts varies systematically with perspective. The analysis of complex concepts indicates that compositionality too should be considered to be sensitive to perspective. Such a view accords with concepts and mental states being situated and the implications for theories of concepts and for computational models of the mind are discussed. (shrink)

The nature of complex concepts has important implications for the computational modelling of the mind, as well as for the cognitive science of concepts. This paper outlines the way in which RVC – a Relational View of Concepts – accommodates a range of complex concepts, cases which have been argued to be non-compositional. RVC attempts to integrate a number of psychological, linguistic and psycholinguistic considerations with the situation-theoretic view that information-carrying relations hold only relative to background situations. The central tenet (...) of RVC is that the content of concepts varies systematically with perspective. The analysis of complex concepts indicates that compositionality too should be considered to be sensitive to perspective. Such a view accords with concepts and mental states being situated and the implications for theories of concepts and for computational models of the mind are discussed. (shrink)

In team-based tasks, successful communication and mutual understanding are essential to facilitate team coordination and performance. It is well-established that an important component of human conversation is the maintenance of common ground. Maintaining common ground has a number of associated processes in which conversational participants engage. Many of these processes are lacking in current synthetic teammates, and it is unknown to what extent this lack of capabilities affects their ability to contribute during team-based tasks. We focused our research on how (...) teams package information within a conversation, by which we mean specifically whether information is explicitly mentioned or implied, and how multiple pieces of information are ordered both within single communications and across multiple communications. We re-analyzed data collected from a simulated remotely-piloted aerial system task in which team members had to specify speed, altitude, and radius restrictions. The data came from three experiments: the “speech” experiment, the “text” experiment, and the “evaluation” experiment. We asked first whether teams settled on a specific routine for communicating the speed, altitude, and radius restrictions, and whether this process was different if the teams communicated in speech compared to text. We then asked how receiving special communication instructions in the evaluation experiment impacted the way the human teammates package information. We found that teams communicating in either speech or text tended to use a particular order for mentioning the speed, altitude, and radius. Different teams also chose different orders from one another. The teams in the evaluation experiment, however, showed unnaturally little variability in their information ordering and were also more likely to explicitly mention all restrictions even when they did not apply. Teams in the speech and text experiments were more likely to leave unnecessary restrictions unmentioned, and were also more likely to convey the restrictions across multiple communications. The option to converge on different packaging routines may have contributed to improved performance in the text experiment compared some of the conditions in the evaluation experiment. (shrink)

Philosophers are often beholden to a picture of language as a largely static, well-defined structure which is handed over from generation to generation by an arduous process of learning: language, on this view, is something that we are given, and that we can make use of, but which we play no significant role in creating ourselves. This picture is often maintained in conjunction with the idea that several distinctively human cognitive capacities could only develop via the language acquisition process, as (...) thus understood. This paper argues that the phenomenon of homesign, i.e., spontaneous gesture systems devised by deaf children for the purpose of communicating with their non-signing peers, can shed valuable empirical light on these convictions. Contrary to grounding assumptions of Wittgensteinian, Gricean, and Peircean approaches to language, homesign shows how core properties of language—including semantic properties—can be built from the ground up in idiosyncratic ways to serve the communicative needs of individuals. (shrink)

A provocative case for the inherently political nature of language In The Politics of Language, David Beaver and Jason Stanley present a radical new approach to the theory of meaning, offering an account of communication in which political and social identity, affect, and shared practices play as important a role as information. This new view of language, they argue, has dramatic consequences for free speech, democracy, and a range of other areas in which speech plays a central role. Drawing on (...) a wealth of disciplines, The Politics of Language argues that the function of speech—whether in dialogue, larger group interactions, or mass communication—is to attune people to something, be it a shared reality, emotion, or identity. Reconceptualizing the central ideas of pragmatics and semantics, Beaver and Stanley apply their account to a range of phenomena that defy standard frameworks in linguistics and philosophy of language—from dog whistles and covert persuasion to echo chambers and genocidal speech. The authors use their framework to show that speech is inevitably political because all communication is imbued with the resonances of particular ideologies and their normative perspectives on reality. At a time when democracy is under attack, authoritarianism is on the rise, and diversity and equality are being demanded, The Politics of Language offers a powerful new vision of the language of politics, ideology, and protest. (shrink)

In this paper, we defend that demonstratives are expressions of joint attention. Though this idea is not exactly new in the philosophical or linguistic literature, we argue here that their proponents have not yet shown how to incorporate these observations into more traditional theories of demonstratives. Our purpose is then to attempt to fill this gap. We argue that coordinated attentional activities are better integrated into a full account of demonstratives as meta-pragmatic information. Our claim is twofold. First, we claim (...) that pragmatically presupposing salience is a fundamental aspect of using demonstratives. Secondly, we hold that the pragmatics of demonstrating can only be properly understood in relation to meta-pragmatic conditions that have to do with joint attention. We use tests of truth-value gap as evidence for our claim. Our proposal provides us with a complete view of what speakers do and presuppose when engaging in acts of demonstrative reference through language. (shrink)

Dialogue has its origins in joint activities, which it serves to coordinate. Joint activities, in turn, usually emerge in hierarchically nested projects and subprojects. We propose that participants use dialogue to coordinate two kinds of transitions in these joint projects: vertical transitions, or entering and exiting joint projects; and horizontal transitions, or continuing within joint projects. The participants help signal these transitions with project markers, words such as uh-huh, m-hm, yeah, okay, or all right. These words have been studied mainly (...) as signals of listener feedback (back-channel signals) or turn-taking devices (acknowledgment tokens). We present evidence from several types of well-defined tasks that they are also part of a system of contrasts specialized for navigating joint projects. Uh-huh, m-hm and yeah are used for horizontal transitions, and okay and all right for vertical transitions. (shrink)

In an ordinary interaction, communicants have various, mostly unconscious goals which reflect their interactional, social and personal needs. In these interactions, people’s minds try to find a balance between reaching these goals and consuming cognitive energy. If a speaker puts too little effort into speech production, she risks not achieving her communicative goals. This is especially typical when the atmosphere is relaxed, a good example of which is family discourse. An analysis of recorded conversations shows that there are certain regular (...) manifestations of risk-taking in family discourse, such as expressing immature thoughts, raising a large variety of topics and overguessing. A substantial amount of risk-taking in family discourse is in one way or another connected with false confidence in the interlocutors’ common ground. Family members know each other well, which results in an overestimation of the similarity of their understanding of words and objects. This attitude leads them to use cryptic, hard-to-comprehend speech. Quick, everyday interactions are mostly automated, and the speakers do not recognise that their speech is full of implicitness and underdeterminacy. (shrink)

Many human cultural traits become increasingly beneficial as they are repeatedly transmitted, thanks to an accumulation of modifications made by successive generations. But how do later generations typically avoid modifications which revert traits to less beneficial forms already sampled and rejected by earlier generations? And how can later generations do so without direct exposure to their predecessors' behavior? One possibility is that learners are sensitive to cues of non‐random production in others' behavior, and that particular variants (e.g., those containing structural (...) regularities unlikely to occur spontaneously) have been produced deliberately and with some effort. If this non‐random behavior is attributed to an informed strategy, then the learner may infer that apparent avoidance of certain possibilities indicates that these have already been sampled and rejected. This could potentially prevent performance plateaus resulting from learners modifying inherited behaviors randomly. We test this hypothesis in four experiments in which participants, either individually or in interacting dyads, attempt to locate rewards in a search grid, guided by partial information about another individual's experience of the task. We find that in some contexts, valid inferences about another's behavior can be made from partial information, and these inferences can be used in a way which facilitates trait adaptation. However, the benefit of these inferences appears to be limited, and in many contexts—including some which have the potential to make inferring the experience of another individual easier—there appears to be no benefit at all. We suggest that inferring previous behavior from partial social information plays a minimal role in the adaptation of cultural traits. (shrink)

In this paper we want to examine how the mutual understanding of speakers is reached during a conversation through collaborative processes, and what role is played by abductive inference (in the Peircean sense) in these processes. We do this by bringing together contributions coming from a variety of disciplines, such as logic, philosophy of language and psychology. When speakers are engaged in a conversation, they refer to a supposed common ground: every participant ascribes to the others some knowledge, belief, opinion (...) etc. on which to rely in order to reach mutual understanding. As the conversation unfolds, this common ground is continually corrected and reshaped by the interchanges. An abductive reasoning takes place, in a collaborative setting, in order to build new possible theories about the common ground. In reconstructing this process through the use of a working example, we argue that the integration of a collaborative perspective within the Peircean theory of abduction can help to solve some of the drawbacks that the critics of the latter have outlined, for example its permissivity and non generativity. (shrink)

In this article we present the bases for a computational theory of the cognitive processes underlying human communication. The core of the article is devoted to the analysis of the phases in which the process of comprehension of a communicative act can be logically divided: (1) literal meaning, where the reconstruction of the mental states literally expressed by the actor takes place: (2) speaker's meaning, where the partner reconstructs the communicative intentions of the actor; (3) communicative effect, where the partner (...) possibly modifies his own beliefs and intentions; (4) reaction, where the intentions for the generation of the response are produced; and (5) response, where an overt response is constructed. The model appears to be compatible with relevant facts about human behavior. Our hypothesis is that, through communication, an actor tries to exploit the motivational structures of a partner so that the desired goal is generated. A second point is that social behavior requires that cooperation be maintained at some level. In the case of communication, cooperation is, in general, pursued even when the partner does not adhere to the actor's goals, and therefore no cooperation occurs at the behavioral level. This important distinction is reflected in the two kinds of game we introduce to account for communication. The main concept implied in communication is that two agents overtly reach a situation of shared mental states. Our model deals with sharedness through two primitives: shared beliefs and communicative intentions. (shrink)

This paper compares two explanations of the process by which human communication systems evolve: iterated learning and social collaboration. It then reports an experiment testing the social collaboration account. Participants engaged in a graphical communication task either as a member of a community, where they interacted with seven different partners drawn from the same pool, or as a member of an isolated pair, where they interacted with the same partner across the same number of games. Participants’ horizontal, pair‐wise interactions led (...) “bottom up” to the creation of an effective and efficient shared sign system in the community condition. Furthermore, the community‐evolved sign systems were as effective and efficient as the local sign systems developed by isolated pairs. Finally, and as predicted by a social collaboration account, and not by an iterated learning account, interaction was critical to the creation of shared sign systems, with different isolated pairs establishing different local sign systems and different communities establishing different global sign systems. (shrink)

This chapter develops an account of the meaning and use of various types of legal claims, and uses this account to inform debates about the nature and normativity of law. The account draws on a general framework for implementing a contextualist theory, called 'Discourse Contextualism' (Silk 2016). The aim of Discourse Contextualism is to derive the apparent normativity of claims of law from a particular contextualist interpretation of a standard semantics for modals, along with general principles of interpretation and conversation. (...) Though the semantics is descriptivist, it avoids Dworkin’s influential criticism of so-called “semantic theories of law,” and elucidates the nature of “theoretical disagreements” about the criteria of legal validity. The account sheds light on the social, interpersonal function of normative uses of language in legal discourse. It also gives precise expression to Hart’s and Raz’s intuitive distinctions among types of legal claims (internal/external, committed/detached), while giving them a uniform type of analysis. The proposed semantics and pragmatics of legal claims provides a fruitful framework for further theorizing about the nature and metaphysics of law, the relation between law and morality, and the apparent practical character of legal language and judgment. Discourse Contextualism provides a solid linguistic basis for a broader account of legal discourse and practice. (shrink)

Speech disfluencies can signal that a speaker is about to refer to something difficult to name. In two experiments, we found evidence that 4-year-olds, like adults, flexibly interpret a particular partner’s disfluency based on their estimate of that partner’s knowledge, derived from the preceding conversation. In entrainment trials, children established partner-specific shared knowledge of names for tangram pictures with one or two adult interlocutors. In each test trial, an adult named one of two visible tangrams either fluently or disfluently while (...) children’s eye-movements were monitored. We manipulated speaker knowledge in the test trials. In Experiment 1, the test-trial speaker was the same speaker from entrainment or a naïve experimenter; in Experiment 2, the test-trial speaker had been one of the child’s partners in entrainment and had seen half of the tangrams. When hearing disfluent expressions, children looked more at a tangram that was unfamiliar from the speaker’s perspective; this systematic disfluency effect disappeared in Experiment 1 when the speaker was entirely naïve, and depended on each speaker’s entrainment experience in Experiment 2. These findings show that 4-year-olds can keep track of two different partners’ knowledge states, and use this information to determine what should be difficult for a particular partner to name, doing so efficiently enough to guide online interpretation of disfluent speech. (shrink)

The way we refer to things in the world is shaped by the immediate physical context as well as the discourse history. But what part of the discourse history is relevant to language use in the present? In four experiments, we combine the study of task‐based conversation with measures of recognition memory to examine the role of physical contextual cues that shape what speakers perceive to be a part of the relevant discourse history. Our studies leverage the differentiation effect, a (...) phenomenon in which speakers are more likely to use a modified expression to refer to an object (e.g., dotted sock) if they had previously described a similar object (e.g., striped sock) than when they had not described a similar object. Two physical cues—the background that framed the to‐be‐described pictures and the position of the pictures in the display—were manipulated to alter perceptions about the relevant discourse context. We measured the rate with which speakers modify referring expressions to differentiate current from past referents. Recognition memory measures following the conversation probed what was and was not remembered about past discourse referents and contexts. Analysis of modification rates indicated that these contextual grouping cues shaped perceptions about the relevant discourse context. The contextual cues did not affect memory for the referents, but the memory for past referents was better for speakers than for listeners. Our findings show that perceptions about the relevant discourse history are a key determinant of how language is used in the moment but also that conversational partners form asymmetric representations of the discourse history. (shrink)

How do speakers design what they say in order to communicate effectively with groups of addressees who vary in their background knowledge of the topic at hand? Prior findings indicate that when a speaker addresses a pair of listeners with discrepant knowledge, that speakers Aim Low, designing their utterances for the least knowledgeable of the two addressees. Here, we test the hypothesis that speakers will depart from an Aim Low approach in order to efficiently communicate with larger groups of interacting (...) partners. Further, we ask whether the cognitive demands of tracking multiple conversational partners' perspectives places limitations on successful audience design. We find that speakers can successfully track information about what up to four of their partners do and do not know in conversation. When addressing groups of 3–4 addressees at once, speakers design language based on the combined knowledge of the group. These findings point to an audience design process that simultaneously represents the perspectives of multiple other individuals and combines these representations in order to design utterances that strike a balance between the different needs of the individuals within the group. (shrink)

Communicating with multiple addressees poses a problem for speakers: Each addressee necessarily comes to the conversation with a different perspective—different knowledge, different beliefs, and a distinct physical context. Despite the ubiquity of multiparty conversation in everyday life, little is known about the processes by which speakers design language in multiparty conversation. While prior evidence demonstrates that speakers design utterances to accommodate addressee knowledge in multiparty conversation, it is unknown if and how speakers encode and combine different types of perspective information. (...) Here we test whether speakers encode the perspective of multiple addressees, and then simultaneously consider their knowledge and physical context during referential design in a three‐party conversation. Analyses of referential form—expression length, disfluency, and elaboration rate—in an interactive multiparty conversation demonstrate that speakers do take into consideration both addressee knowledge and physical context when designing utterances, consistent with a knowledge‐scene integration view. These findings point to an audience design process that takes as input multiple types of representations about the perspectives of multiple addressees, and that bases the informational content of the to‐be‐designed utterance on a combination of the perspectives of the intended addressees. (shrink)

Spatial communications are essential to the survival and social interaction of human beings. In science fiction and the near future, robots are supposed to be able to understand spatial languages to collaborate and cooperate with humans. However, it remains unknown whether human speakers regard robots as human-like social partners. In this study, human speakers describe target locations to an imaginary human or robot addressee under various scenarios varying in relative speaker–addressee cognitive burden. Speakers made equivalent perspective choices to human and (...) robot addressees, which consistently shifted according to the relative speaker–addressee cognitive burden. However, speakers’ perspective choice was only significantly correlated to their social skills when the addressees were humans but not robots. These results suggested that people generally assume robots and humans with equal capabilities in understanding spatial descriptions but do not regard robots as human-like social partners. (shrink)

It makes sense that the more information people share, the better they communicate. To evaluate the effect of knowledge overlap on the effectiveness of communication, participants played a communication game where the “director” identified objects to the “addressee”. Pairs either shared information about most objects' names (high overlap), or about the minority of objects' names (low overlap). We found that high-overlap directors tended to use more names than low overlap directors. High overlap directors also used more names with objects whose (...) names only they knew, thereby confusing their addressees more often than low-overlap directors. We conclude that while sharing more knowledge can be beneficial to communication overall, it can cause communication to be locally ineffective. Sharing more information reduces communication effectiveness precisely when there is an opportunity to inform—when people communicate information only they themselves know. (shrink)