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Although many neuroimaging studies have investigated adolescent risk taking, few studies have dissociated between decision-making under risk (known probabilities) and ambiguity (unknown probabilities). Furthermore, which brain regions are sensitive to individual differences in task-related and self-reported risk taking remains elusive. We presented 198 adolescents (11–24 years, an age-range in which individual differences in risk taking are prominent) with an fMRI paradigm that separated decision-making (choosing to gamble or not) and reward outcome processing (gains, no gains) under risky and ambiguous conditions, and related this to task-related and self-reported risk taking. We observed distinct neural mechanisms underlying risky and ambiguous gambling, with risk more prominently associated with activation in parietal cortex, and ambiguity more prominently with dorsolateral prefrontal cortex (PFC), as well as medial PFC during outcome processing. Individual differences in task-related risk taking were positively associated with ventral striatum activation in the decision phase, specifically for risk, and negatively associated with insula and dorsomedial PFC activation, specifically for ambiguity. Moreover, dorsolateral PFC activation in the outcome phase seemed a prominent marker for individual differences in task-related risk taking under ambiguity as well as self-reported daily-life risk taking, in which greater risk taking was associated with reduced activation in dorsolateral PFC. Together, this study demonstrates the importance of considering multiple risk-taking measures, and contextual moderators, in understanding the neural mechanisms underlying adolescent risk taking. [ABSTRACT FROM AUTHOR]

People take longer to categorize racially ambiguous individuals, but does this perceptual complexity also affect social interactions? In Study 1, White participants interacted with a racially ambiguous confederate who was either labeled as biracial Black/White, monoracial Black, or given no racial label. White participants in the biracial condition were significantly less cognitively depleted, less essentialist in their thoughts about race, and exhibited more accurate face memory for their partners than when partner race remained unspecified or was labeled as monoracial Black. Confederate reports and nonverbal behavior in the biracial condition were also more positive. In Study 2, White participants perceived more similarity with a biracial Black/White labeled interaction partner compared to a Black-specified or race-unspecified partner, highlighting for the first time how racial ambiguity and racial labeling affect behavioral outcomes in social interactions. [ABSTRACT FROM AUTHOR]

We introduce linguistic ambiguity into a principal–agent contracting framework. Contracts are drafted in a common language. Nevertheless, the principal and the agent may ultimately disagree about the terms of the contract that apply ex post . We presume that both parties are ambiguity averse and for tractability reasons that their preferences take a recursive constant absolute risk averse (RCARA) form. We consider various dispute resolution regimes and analyze how the optimal dispute resolution regime depends on the ambiguity attitudes of the parties. We also provide an axiomatization of the class of RCARA preferences. [ABSTRACT FROM AUTHOR]

Verb bias-the co-occurrence frequencies between a verb and the syntactic structures it may appear with-is a critical and reliable linguistic cue for online sentence processing. In particular, listeners use this information to disambiguate sentences with multiple potential syntactic parses (e.g., Feel the frog with the feather.). Further, listeners dynamically update their representations of specific verbs in the face of new evidence about verb-structure co-occurrence. Yet, little is known about the biological memory systems that support the use and dynamic updating of verb bias. We propose that hippocampal-dependent declarative (relational) memory represents a likely candidate system because it has been implicated in the flexible binding of relational co-occurrences and in statistical learning. We explore this question by testing patients with severe and selective deficits in declarative memory (anterograde amnesia), and demographically matched healthy participants, in their on-line interpretation of ambiguous sentences and the ability to update their verb bias with experience. We find that (1) patients and their healthy counterparts use existing verb bias to successfully interpret on-line ambiguity, however (2) unlike healthy young adults, neither group updated these biases in response to recent exposure. These findings demonstrate that using existing representations of verb bias does not necessitate involvement of the declarative memory system, but leave open the question of whether the ability to update representations of verb-specific biases requires hippocampal engagement. [ABSTRACT FROM AUTHOR]

An MEG study investigated the role of context in semantic interpretation by examining the comprehension of ambiguous words in contexts leading to different interpretations. We compared high-ambiguity words in minimally different contexts (to bowl, the bowl) to low-ambiguity counterparts (the tray, to flog). Whole brain beamforming revealed the engagement of left inferior frontal gyrus (LIFG) and posterior middle temporal gyrus (LPMTG). Points of interest analyses showed that both these sites showed a stronger response to verb-contexts by 200 ms post-stimulus and displayed overlapping ambiguity effects that were sustained from 300 ms onwards. The effect of context was stronger for high-ambiguity words than for low-ambiguity words at several different time points, including within the first 100 ms post-stimulus. Unlike LIFG, LPMTG also showed stronger responses to verb than noun contexts in low-ambiguity trials. We argue that different functional roles previously attributed to LIFG and LPMTG are in fact played out at different periods during processing. [ABSTRACT FROM AUTHOR]

Speech carries accent information relevant to determining the speaker’s linguistic and social background. A series of web-based experiments demonstrate that accent cues can modulate access to word meaning. In Experiments 1–3, British participants were more likely to retrieve the American dominant meaning (e.g., hat meaning of “bonnet”) in a word association task if they heard the words in an American than a British accent. In addition, results from a speeded semantic decision task (Experiment 4) and sentence comprehension task (Experiment 5) confirm that accent modulates on-line meaning retrieval such that comprehension of ambiguous words is easier when the relevant word meaning is dominant in the speaker’s dialect. Critically, neutral-accent speech items, created by morphing British- and American-accented recordings, were interpreted in a similar way to accented words when embedded in a context of accented words (Experiment 2). This finding indicates that listeners do not use accent to guide meaning retrieval on a word-by-word basis; instead they use accent information to determine the dialectic identity of a speaker and then use their experience of that dialect to guide meaning access for all words spoken by that person. These results motivate a speaker-model account of spoken word recognition in which comprehenders determine key characteristics of their interlocutor and use this knowledge to guide word meaning access. [ABSTRACT FROM AUTHOR]

Computer-based dreams content analysis relies on word frequencies within predefined categories in order to identify different elements in text. As a complementary approach, we explored the capabilities and limitations of word-embedding techniques to identify word usage patterns among dream reports. These tools allow us to quantify words associations in text and to identify the meaning of target words. Word-embeddings have been extensively studied in large datasets, but only a few studies analyze semantic representations in small corpora. To fill this gap, we compared Skip-gram and Latent Semantic Analysis (LSA) capabilities to extract semantic associations from dream reports. LSA showed better performance than Skip-gram in small size corpora in two tests. Furthermore, LSA captured relevant word associations in dream collection, even in cases with low-frequency words or small numbers of dreams. Word associations in dreams reports can thus be quantified by LSA, which opens new avenues for dream interpretation and decoding. [ABSTRACT FROM AUTHOR]

In this work, we exploit the power of finite ambiguity for the complementation problem of Büchi automata by using reduced run directed acyclic graphs (DAGs) over infinite words, in which each vertex has at most one predecessor; these reduced run DAGs have only a finite number of infinite runs, thus obtaining the finite ambiguity in Büchi complementation. We show how to use this type of reduced run DAGs as a unified tool to optimize both rank-based and slice-based complementation constructions for Büchi automata with a finite degree of ambiguity. As a result, given a Büchi automaton with n states and a finite degree of ambiguity, the number of states in the complementary Büchi automaton constructed by the classical rank-based and slice-based complementation constructions can be improved from 2 O (n log ⁡ n) and O ((3 n) n) to O (6 n) ⊆ 2 O (n) and O (4 n) , respectively. We further show how to construct such reduced run DAGs for limit deterministic Büchi automata and obtain a specialized complementation algorithm, thus demonstrating the generality of the power of finite ambiguity. [ABSTRACT FROM AUTHOR]

The paper demonstrates the non-closure of the family of unambiguous linear languages (that is, those defined by unambiguous linear context-free grammars) under complementation. To be precise, a particular unambiguous linear grammar is presented, and it is proved that the complement of this language is not defined by any context-free grammar. This also constitutes an alternative proof for the result of Hibbard and Ullian ("The independence of inherent ambiguity from complementedness among context-free languages", JACM , 1966) on the non-closure of the unambiguous languages under complementation. [ABSTRACT FROM AUTHOR]

• Patients who have gone through FLR show difficulties with decision-making under ambiguity. • They fail to learn from feedback throughout the Iowa Gambling Task. • Decision-making under ambiguity was not correlated to results in executive tasks. Decision-making is crucial to daily life and can impact our society as well as economic conditions. Although the frontal lobes have been identified as important for decision-making, this capacity has only been studied to a limited extent in frontal lobe epilepsy and not at all after frontal lobe resection (FLR) for epilepsy. This study aimed to explore decision-making under ambiguity after FLR for epilepsy. Fourteen patients having undergone FLR for epilepsy completed the Iowa Gambling Task (IGT) which is a widely used tool to measure decision-making under ambiguity. Iowa Gambling Task scores included in the analysis were: total net score, separate scores from five blocks across the test, and a change score (last block of IGT minus first block). A group of healthy controls (n = 30) was used as a comparison. Associations between IGT and standardized neuropsychological methods for assessment of executive functions, self-rating questionnaires of mental health, fatigue, and behavior linked to frontal lobe dysfunction were also investigated. The patient group performed inferior to controls at the final block of the IGT (p =.001). A group difference in IGT change scores was found (p =.005), reflecting the absence of a positive change in performance over time for the FLR group compared to the control group. Correlations with tests of executive functions as well as self-rating scales were mainly statistically nonsignificant. This study shows that patients having undergone FLR for epilepsy have difficulties with decision-making under ambiguity. The performance illustrated a failure to learn throughout the task. Executive as well as emotional deficits may impact decision-making processes in this patient group and need to be considered in further studies. Prospective studies with larger cohorts are needed. [ABSTRACT FROM AUTHOR]

We obtain exact formulas for the differential spectrum, deficiency and ambiguity of all normalized permutation polynomials of degree up to six over finite fields. [ABSTRACT FROM AUTHOR]

People often make decisions in the face of ambiguous information, but it remains unclear how ambiguity is represented in the brain. We used three types of ambiguous stimuli and combined EEG and fMRI to examine the neural representation of perceptual decisions under ambiguity. We identified a late positive potential, the LPP, which differentiated levels of ambiguity, and which was specifically associated with behavioral judgments about choices that were ambiguous, rather than passive perception of ambiguous stimuli. Mediation analyses together with two further control experiments confirmed that the LPP was generated only when decisions are made (not during mere perception of ambiguous stimuli), and only when those decisions involved choices on a dimension that is ambiguous. A further control experiment showed that a stronger LPP arose in the presence of ambiguous stimuli compared to when only unambiguous stimuli were present. Source modeling suggested that the LPP originated from multiple loci in cingulate cortex, a finding we further confirmed using fMRI and fMRI-guided ERP source prediction. Taken together, our findings argue for a role of an LPP originating from cingulate cortex in encoding decisions based on task-relevant perceptual ambiguity, a process that may in turn influence confidence judgment, response conflict, and error correction. [ABSTRACT FROM AUTHOR]

Ambiguity aversion arises when a decision maker prefers risky gambles with known probabilities over equivalent ambiguous gambles with unknown probabilities. This phenomenon has been consistently observed in adults across a large body of empirical work. Evaluating ambiguity aversion in young children, however, has posed methodological challenges because probabilistic representations appropriate for adults might not be understood by young children. Here, we established a novel method for representing risk and ambiguity with physical objects that overcomes previous methodological limitations and allows us to measure ambiguity aversion in young children. We found that individual 5-year-olds exhibited consistent choice preferences and, as a group, exhibited no ambiguity aversion in a task that evokes ambiguity aversion in adults. Across individuals, 5-year-olds exhibited greater variance in ambiguity preferences compared with adults tested under similar conditions. This suggests that ambiguity aversion is absent during early childhood and emerges over the course of development. [ABSTRACT FROM AUTHOR]

I study the implications of Wald's (1947) complete class theorem for decision making under Knightian uncertainty (or ambiguity). Suppose we call someone who uses Wald's approach to statistical decision making a Waldian. A Waldian may then have preferences over acts that are not in agreement with subjective expected utility but always chooses as if she was a subjective expected utility maximizer. In particular, even Wald's (1945) minmax decision rule is consistent with subjective expected utility. [ABSTRACT FROM AUTHOR]

We study cheap talk communication in a simple two actions-two states model featuring an ambiguous state distribution. Equilibrium behavior of both sender (S) and receiver (R) features mixing and we relate each agent's randomization to a specific mode of ambiguous communication. For sufficiently high ambiguity, implementing the S-optimal decision rule with only two messages is impossible if R has aligned preferences. This may in contrast be possible if R has misaligned preferences. Adding a little ambiguity may generate influential communication that is unambiguously advantageous to S. [ABSTRACT FROM AUTHOR]

Scholars have long recognized status and reputation as pervasive forces reproducing comparative advantage in social and economic systems. Yet, due in part to methodological challenges, relatively few studies have examined how status and reputation interact. We use data from an online market for peer-to-peer lending to study independent and joint effects of status and reputation on borrowers’ success at obtaining loans. First, we find a positive main effect of status, even when reputational signals are reliable and abundant. Second, we find that status matters the most for borrowers with moderate (rather than high or low) reputations, suggesting a curvilinear effect of status x reputation on loans. These results support the idea that status matters not only under conditions of too little information that creates information asymmetry, as typically assumed, but also under conditions of abundant information and too many choices that creates ambiguity about how to evaluate candidates. [ABSTRACT FROM AUTHOR]

Based on a model where deviations from equilibrium play are assumed to identify irrational players who are characterized by ambiguous set-valued strategies, this paper introduces an equilibrium notion for extensive games with ambiguity averse players that yields a precise interpretation for the counterfactual reasoning usually associated with backward induction. The resulting equilibria are always Nash equilibria, but may not satisfy the conditions required for various refinements of Nash equilibrium, including those for subgame perfection. Existence of such equilibria is proved for all two-player games, and for N -player games with perfect information. [ABSTRACT FROM AUTHOR]

To successfully comprehend a sentence that contains a homonym, readers must select the ambiguous word's context-appropriate meaning. The outcome of this process is influenced both by top-down contextual support and bottom-up, word-specific characteristics. We examined how these factors jointly affect the neural signatures of lexical ambiguity resolution. We measured the similarity between multi-voxel patterns evoked by the same homonym in two distinct linguistic contexts: once after subjects read sentences that biased interpretation toward each homonym's most frequent, dominant meaning, and again after interpretation was biased toward a weaker, subordinate meaning. We predicted that, following a subordinate-biasing context, the dominant yet inappropriate meaning would nevertheless compete for activation, manifesting in increased similarity between the neural patterns evoked by the two word meanings. In left anterior temporal lobe (ATL), degree of within-word pattern similarity was positively predicted by the association strength of each homonym's dominant meaning. Further, within-word pattern similarity in left ATL was negatively predicted by item-specific responses in a region of left ventrolateral prefrontal cortex (VLPFC) sensitive to semantic conflict. These findings have implications for psycholinguistic models of lexical ambiguity resolution, and for the role of left VLPFC function during this process. Moreover, these findings demonstrate the utility of item-level, similarity-based analyses of fMRI data for our understanding of competition between co-activated word meanings during language comprehension. [ABSTRACT FROM AUTHOR]

This paper examines climate-change benefit-cost analysis in the presence of scientific uncertainty in the form of ambiguity. The specific issue addressed is the robustness of benefit-cost analyses of climate-change policy alternatives to relaxation of Savage's original axioms. Two alternatives to subjective expected utility (SEU) are considered: maximin expected utility (MEU) and incomplete expected utility (IEU). Among other results, it is demonstrated that polar opposite recommendations can emerge in an ambiguous decision setting even if all agree on Society's rate of time preference, Society's risk attitudes, the degree of ambiguity faced, and the scientific primitives. We show that, for a simple numerical simulation of our model, an MEU decision maker favors policies which immediately tackle climate change while an IEU decision prefers “business as usual”.“Each agency shall assess the costs and benefits of the intended regulation, and recognizing that some costs and benefits are difficult to quantify, propose or adopt a regulation only upon a reasoned determination that the benefits of the intended regulation justify its cost.” Executive Order 12866 of the US President. [ABSTRACT FROM AUTHOR]

A crucial challenge regarding the single image deraining task is to completely remove rain streaks while still preserving explicit image details. Due to the inherent overlapping between rain streaks and background scenes, the texture details could be inevitably lost when clearing rain away from the degraded image, making the two purposes contradictory. Existing deep learning based approaches endeavor to resolve the two issues successively in a cascaded framework or to treat them as independent tasks in a parallel structure. However, none of the models explores a proper interaction between rain distributions and hidden feature responses, which intuitively would provide more clues to facilitate the procedures of rain streak removal as well as detail restoration. In this paper, we investigate the impact of rain streak detection for single image deraining and propose a novel deep network with dual stimulations, namely, DSDNet. The proposed DSDNet utilizes a dual-stream pipeline to separately estimate rain streaks and a loss of details, and more importantly, an additional mask that indicates both location and intensity of rains is jointly predicted. In particular, the rain mask is involved in a tailored stimulation strategy that is deployed into each stream of the proposed model, serving as guidance for allowing the network to focus on rain removal and detail recovery in rain regions rather than non-rain areas. Moreover, we incorporate a self-paced semi-curriculum learning design to alleviate the learning ambiguity brought by the prediction of the rain mask and thus accelerate the training process. Extensive experiments demonstrate the proposed method outperforms the state-of-the-art methods on several benchmarks, including in both synthetic and real-world scenarios. The effectiveness of the proposed method is also validated via joint single image deraining, detection, and segmentation tasks. • A stimulation strategy that adjusts feature responses for image deraining. • A curriculum learning scheme that mitigates the ambiguity brought by the rain mask. • Superior performance against the sotas in deraining or other downstream applications. [ABSTRACT FROM AUTHOR]

To detect flip ambiguity for range-based three-dimensional nodes localization in wireless sensor networks, we have proposed and proved that flip ambiguity detection for three-dimensional node localization is equivalent to finding the intersecting plane that intersects with all range error spheres of the reference nodes of unknown node in the ideal radio model, which is called the existence of intersecting plane (EIP) problem. To solve EIP problem, we further have proposed two algorithms: common tangent plane algorithm (CTP) and orthogonal projection algorithm (OP). The simulation results demonstrate that the computation complexity of OP is lower than CTP, while the detection results of OP is comparable with CTP. [ABSTRACT FROM AUTHOR]

[Display omitted] • We present the most comprehensive phylogeny for the crab superfamily Xanthoidea. • Results upend conventional morphology-based classification. • 6 xanthoidean families are recognized including revised subfamilial classification. • Diversification in xanthoid crabs is not associated with habitat depth. Maximum likelihood and Bayesian phylogenies for the brachyuran crab superfamily Xanthoidea were estimated based on three mitochondrial and four nuclear genes to infer phylogenetic relationships and inform taxonomy. Habitat data was then used in conjunction with several diversification rates analyses (BAMM, BiSSE, HiSSE, and FiSSE) to test evolutionary hypotheses regarding the diversification of xanthoid crabs. The phylogenies presented are the most comprehensive to date in terms of global diversity as they include all four constituent families (Xanthidae, Panopeidae, Pseudorhombilidae, and Linnaeoxanthidae) spanning all oceans in which xanthoid crabs occur. Six Xanthoidea families are recognised. Panopeidae and Xanthidae sensu stricto are the two largest family-level clades, which are reciprocally monophyletic. Pseudorhombilidae is nested within and is here treated as a subfamily of Panopeidae. Former subfamilies or tribes of Xanthidae sensu lato are basally positioned clades in Xanthoidea and are here assigned family-level ranks: Garthiellidae, Linnaeoxanthidae, Antrocarcinidae, and Nanocassiopidae. The genera Linnaeoxantho and Melybia were recovered in separate clades with Linnaeoxantho being sister to the family Antrocarcinidae, while Melybia was recovered within the family Panopeidae. The existing subfamily classification of Xanthidae and Panopeidae is drastically restructured with 20 xanthid and four panopeid subfamilies provisionally recognised. Diversification-time analyses inferred the origin of Xanthoidea and Garthiellidae in the Eocene, while the other families originated during the Oligocene. The majority of genus- and species-level diversification took place during the Miocene. Ancestral state reconstruction based on depth of occurrence (shallow vs. deep water) shows some ambiguity for the most recent common ancestor of Xanthoidea and Nanocassiopidae. The most recent common ancestors of Antrocarcinidae and Panopeidae were likely deep-water species, while those of Garthiellidae and Xanthidae were probably shallow-water species. Several shifts in net diversification rates were detected but they were not associated with depth-related habitat transitions. [ABSTRACT FROM AUTHOR]

Social group identity plays a central role in political polarization and inter-party conflict. Here, we use ambiguously valenced faces to measure bias in the processing of political ingroup and outgroup faces, while also accounting for inter-party differences in judgments of emotion at baseline. Participants identifying as Democrats and Republicans judged happy, angry, and surprised faces as positive or negative. Whereas happy and angry faces convey positive and negative valence respectively, surprised faces are ambiguous in that they readily convey positive and negative valence. Thus, surprise is a useful tool for characterizing valence bias (i.e., the tendency to judge ambiguous stimuli as negative). Face stimuli were assigned to the participants' political ingroup or outgroup, or a third group with an unspecified affiliation (baseline). We found a significant interaction of facial expression and group membership, such that outgroup faces were judged more negatively than ingroup and baseline, but only for surprise. There was also an interaction of facial expression and political affiliation, with Republicans judging surprise more negatively than Democrats across all group conditions. However, we did not find evidence for party differences in outgroup negativity. Our findings demonstrate the utility of judgments of surprised faces as a measure of intergroup bias, and reinforce the importance of outgroup negativity (relative to ingroup positivity) for explaining inter-party biases. • Republicans and Democrats viewed emotional faces of ingroup and outgroup members. • Emotional ambiguity was associated with a bias towards outgroup negativity. • There was no evidence of ingroup positivity. • Parties differed in their overall tendency to judge surprise as negative (R > D). [ABSTRACT FROM AUTHOR]

A morphism g is ambiguous with respect to a word u if there exists a second morphism h ≠ g such that g (u) = h (u). Otherwise g is unambiguous with respect to u. Thus unambiguous morphisms are those for which the structure of the morphism is preserved in the image. Ambiguity has so far been studied for morphisms of free monoids, where several characterisations exist for the set of words u permitting an (injective) unambiguous morphism. In the present paper, we consider ambiguity of morphisms of free groups, and consider possible analogies to the existing characterisations in the free monoid. While a direct generalisation results in a trivial situation where all morphisms are ambiguous, we discuss some natural and well-motivated reformulations, and provide a characterisation of words in a free group that permit a morphism which is "as unambiguous as possible". [ABSTRACT FROM AUTHOR]

Many recent discussions have focused on the role of replication in psychological science. In this article, we examine three key issues in evaluating the conclusions that follow from results of studies at least partly aimed at replicating previous results: the evaluation and status of exact versus conceptual replications, the statistical evaluation of replications, and the robustness of research findings to potential existing or future “non-replications.” In the first section of the article, we discuss the sources of ambiguity in evaluating failures to replicate in exact as well as conceptual replications. In addressing these ambiguities, we emphasize the key role of psychometric invariance of the independent and dependent variables in evaluations of replications. In the second section of the article, we use a meta-analytic framework to discuss the statistical status of replication attempts. We emphasize meta-analytic tools that have been used too sparingly, especially in evaluation of sets of studies within a single article or focused program of research. In the final section of the article, we extend many of these meta-analytic tools to the evaluation of the robustness of a body of research to potential existing or future failures to replicate previous statistically significant results. [ABSTRACT FROM AUTHOR]

Workplace incivility is a widespread phenomenon that silently damages many organizations and people working within them. To better understand moderators of the relationship between experienced incivility and employees' decision to leave, we conducted a two-wave study that examined a sample of 618 nurses working in a public research hospital. Whereas previous research has focused on preventing and eradicating uncivil behaviors, our study investigates factors that enhance or buffer the negative consequences of incivility. Building on theories of job resources and job demands, we show that (a) certain structural demands (i.e., role ambiguity and working in the night shift) increase the relationship of workplace incivility with turnover intentions, while (b) organization-provided resources (i.e., team-building and personal management interviews) help organizations reduce the association of incivility with turnover intentions. [ABSTRACT FROM AUTHOR]

Many participatory processes fail to generate social change and collaborative outcomes. This failure can partly be explained by how divergent stakeholders' frames are handled. This paper builds on the framing and participation literature to explain how facilitators can manage frame diversity and foster collaborative outcomes. It suggests two pragmatic steps: identifying frames and managing frames. The two steps are applied to a participatory process for natural resource management in Fogera, Ethiopia. Effectiveness of facilitators’ strategies to manage frame diversity in the Fogera case is discussed. Two main elements challenging effectiveness are identified: counter-strategies used by facilitators and most-powerful stakeholders, and the constraining factors knowledge, champions and frame sponsorship. We argue that these elements need to be taken into account by participatory process facilitators when managing frame diversity. [ABSTRACT FROM AUTHOR]

Quantifier words like each , every , all and three are among the most abstract words in language. Unlike nouns, verbs and adjectives, the meanings of quantifiers are not related to a referent out in the world. Rather, quantifiers specify what relationships hold between the sets of entities, events and properties denoted by other words. When two quantifiers are in the same clause, they create a systematic ambiguity. “ Every kid climbed a tree ” could mean that there was only one tree, climbed by all, or many different trees, one per climbing kid. In the present study, participants chose a picture to indicate their preferred reading of different ambiguous sentences – those containing every , as well as the other three quantifiers. In Experiment 1, we found large systematic differences in preference, depending on the quantifier word. In Experiment 2, we then manipulated the choice of a particular reading of one sentence, and tested how this affected participants’ reading preference on a subsequent target sentence. We found a priming effect for all quantifiers, but only when the prime and target sentences contained the same quantifier. For example, all-a sentences prime other all-a sentences, while each-a primes each-a , but sentences with each do not prime sentences with all or vice versa. In Experiment 3, we ask whether the lack of priming across quantifiers could be due to the two sentences sharing one fewer word. We find that changing the verb between the prime and target sentence does not reduce the priming effect. In Experiment 4, we discover one case where there is priming across quantifiers – when one number (e.g. three ) is in the prime, and a different one (e.g. four ) is in the target. We discuss how these findings relate to linguistic theories of quantifier meaning and what they tell us about the division of labor between conceptual content and combinatorial semantics, as well as the mental representations of quantification and of the abstract logical structure of language. [ABSTRACT FROM AUTHOR]

While the first individuals to discover and maintain territories are generally respected as owners, under some conditions there may be ambiguity as to who got there first. Here we attempt to understand the evolutionary consequences of this ambiguity by developing a pair of game-theoretic models in which we explicitly consider rival residency-based claims to ownership. Following earlier qualitative explanations for residency effects, we assume that either the value of the territory (Model A) or an interloper׳s self-belief that it is the owner (Model B) increases with duration of residency. Model A clearly demonstrates that if the value of a territory increases to a resident over time, so should its motivation to fight in terms of the effort it invests in fighting. Indeed, only a small increase in territory value with residency duration can be sufficient for longer established residents to win disputes, even without any arbitrary convention or other form of priority effect. Likewise, Model B shows that the observed increase in fighting persistence with residency duration can be readily explained as a consequence of increasing confidence on behalf of the interloper that it is the rightful owner. Collectively, the models help to explain some general findings long observed by empiricists, and shed light on the nature of conflicts that can arise when individuals do not have complete information about rival claims to ownership. [ABSTRACT FROM AUTHOR]

The brain is capable of producing coordinated fast changing neural dynamics across multiple brain regions in order to adapt to rapidly changing environments. However, it is non-trivial to identify multiregion dynamics at fast sub-second time-scales in electrophysiological data. We propose a method that, with no knowledge of any task timings, can simultaneously identify and describe fast transient multiregion dynamics in terms of their temporal, spectral and spatial properties. The approach models brain activity using a discrete set of sequential states, with each state distinguished by its own multiregion spectral properties. This can identify potentially very short-lived visits to a brain state, at the same time as inferring the state's properties, by pooling over many repeated visits to that state. We show how this can be used to compute state-specific measures such as power spectra and coherence. We demonstrate that this can be used to identify short-lived transient brain states with distinct power and functional connectivity (e.g., coherence) properties in an MEG data set collected during a volitional motor task. [ABSTRACT FROM AUTHOR]

Strong social and legal norms in the United States discourage the overt expression of bias against ethnic and racial minorities, increasing the attributional ambiguity of Whites' positive behavior to ethnic minorities. Minorities who suspect that Whites' positive overtures toward minorities are motivated more by their fear of appearing racist than by egalitarian attitudes may regard positive feedback they receive from Whites as disingenuous. This may lead them to react to such feedback with feelings of uncertainty and threat. Three studies examined how suspicion of motives relates to ethnic minorities' responses to receiving positive feedback from a White peer or same-ethnicity peer (Experiment 1), to receiving feedback from a White peer that was positive or negative (Experiment 2), and to receiving positive feedback from a White peer who did or did not know their ethnicity (Experiment 3). As predicted, the more suspicious Latinas were of Whites' motives for behaving positively toward minorities in general, the more they regarded positive feedback from a White peer who knew their ethnicity as disingenuous and the more they reacted with cardiovascular reactivity characteristic of threat/avoidance, increased feelings of stress, heightened uncertainty, and decreased self-esteem. We discuss the implications for intergroup interactions of perceptions of Whites' motives for nonprejudiced behavior. [ABSTRACT FROM AUTHOR]

As a result of prevalent pressure to inhibit prejudice, racial minorities may wonder whether White people's nonprejudiced behavior is primarily motivated by personal commitments to egalitarianism (i.e., internal motivation) or superficial efforts to appear nonprejudiced (i.e., external motivation). The present work investigated whether minority group members chronically suspicious of White people's motives (i.e., those who believe White people are more externally than internally motivated), are more accurate than those who are less suspicious in detecting the motives behind White individuals' pleasant behavior toward minorities. Minority participants viewed four videos of White targets engaging in dyadic interracial interactions with a Black peer and evaluated the White targets' motivations. Compared to those low in suspicion, those high in suspicion were more accurate at assessing White targets' actual levels of external motivation. Hence, suspicion seems to carry some functional benefit as it attunes minority-group members to Whites' externally motivated positivity. [ABSTRACT FROM AUTHOR]

Certain built environments can decrease aesthetic appeal. For humans and objects, deviation from typical appearances leads to nonlinear appraisal characterized as the uncanny valley. The first time, it was explored whether an uncanny valley can be found for built environments. In Experiment 1, a cubic N -shaped function of uncanniness plotted against realism of built environments was found, indicating an uncanny valley. Quantitative and qualitative data indicate an association between uncanniness and structural anomalies. Experiment 2 explored distortions leading to uncanniness of indoor places. In Experiment 3, human presence decreased uncanniness of distorted indoor public places but increased uncanniness of private rooms. Taken together, the evidence indicates that deviations from familiar configural patterns drive uncanniness of built physical places. Thus, strong deviations from a built environment's predictable pattern decreases its aesthetic appeal. • Place uncanniness and realism is best explained by an "uncanny valley" function. • Structural deviations predict place uncanniness. • Social presence reduces uncanniness of public, but increases it in private places. [ABSTRACT FROM AUTHOR]

The vector type of interaction of the Thirring–Wess model was replaced by the chiral type and a new model was presented which was termed as chiral Thirring–Wess model in Rahaman (2015). The model was studied there with a Faddeevian class of regularization. Few ambiguity parameters were allowed there with the apprehension that unitarity might be threatened like the chiral generation of the Schwinger model. In the present work it has been shown that no counter term containing the regularization ambiguity is needed for this model to be physically sensible. So the chiral Thirring–Wess model is studied here without the presence of any ambiguity parameter and it has been found that the model not only remains exactly solvable but also does not lose the unitarity like the chiral generation of the Schwinger model. The phase space structure and the theoretical spectrum of this new model have been determined in the present scenario. The theoretical spectrum is found to contain a massive boson with ambiguity free mass and a massless boson. [ABSTRACT FROM AUTHOR]

Individuals differ in their ability to attribute actions to self or other. This variance is thought to explain, in part, the experience of voice-hearing. Misattribution can also be context-driven. For example, causal ambiguity can arise when the actions of two or more individuals are coordinated and produce similar effects (e.g., music-making). Experience in such challenging contexts may refine skills of action attribution. Forty participants completed a novel finger-tapping task which parametrically manipulated the proportion of control that ‘self’ versus ‘other’ possessed over resulting auditory tones. Results showed that action misattribution peaked in the middle of the self-to-other continuum and was biased towards other. This pattern was related to both high hallucination-proneness and to low musical-experience. Findings suggest not only that causal ambiguity plays a key role in agency but also that action attribution abilities may improve with practice, potentially providing an avenue for remediation of the positive symptoms of schizophrenia. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate how 3- to 5-year-old children ( N = 150) identify an object when they are confronted with conflicting evidence, notably when the available perceptual evidence is contradicted by the testimony of either a lone informant or a three-informant consensus. Results showed that (a) 5-year-olds were more likely than 3- or 4-year-olds to rely on the perceptual evidence, ignoring claims made by the informants; (b) the three-informant consensus had more impact than a single informant for all age groups; and (c) children were more likely to make a perception-based response if the stimulus was perceptually unambiguous rather than equivocal with respect to its identity. Moreover, when children’s task was to identify equivocal stimuli, they endorsed the three-informant consensus more than the lone informant. In contrast, when they needed to identify unambiguous stimuli, the number of informants did not influence children’s responses. Taken together, the results show that the tendency to resist testimony on the basis of perceptual evidence increases with age. Moreover, preschoolers monitor both the characteristics of their informants and the relative ambiguity of the perceptual stimuli when they need to weigh verbal testimony against perceptual evidence. [ABSTRACT FROM AUTHOR]

This paper describes an efficient implementation of triplet-based measures of stability, in the program TNT. The only available implementations of such measures are much slower than the present one, either because of an inefficient implementation (Phyutility, Thor) or because the stability is evaluated with quartets (RogueNaRok, requiring O ( t 4 ), instead of the O ( t 3 ) possible for triplets). The method to quickly calculate triplets is applied to solving IterPCR (Pol and Escapa, 2009). It is shown that, in some cases, IterPCR or other algorithms in the program TNT (e.g. commands prunnelsen , prunmajor , or chkmoves ) produce more informative results than analysis with RogueNaRok. [ABSTRACT FROM AUTHOR]

In the context of continuing uncertainty, ambiguity and ignorance in impact assessment (IA) prediction, the case is made that existing IA processes are based on false ‘normal’ assumptions that science can solve problems and transfer knowledge into policy. Instead, a ‘post-normal science’ approach is needed that acknowledges the limits of current levels of scientific understanding. We argue that this can be achieved through embedding evolutionary resilience into IA; using participatory workshops; and emphasising adaptive management. The goal is an IA process capable of informing policy choices in the face of uncertain influences acting on socio-ecological systems. We propose a specific set of process steps to operationalise this post-normal science approach which draws on work undertaken by the Resilience Alliance. This process differs significantly from current models of IA, as it has a far greater focus on avoidance of, or adaptation to (through incorporating adaptive management subsequent to decisions), unwanted future scenarios rather than a focus on the identification of the implications of a single preferred vision. Implementing such a process would represent a culture change in IA practice as a lack of knowledge is assumed and explicit, and forms the basis of future planning activity, rather than being ignored. [ABSTRACT FROM AUTHOR]

Standard economic models cannot capture the fact that information is often ambiguous , and is interpreted in multiple ways. Using a framework that distinguishes between the language in which statements are made and the interpretation of statements, we demonstrate that, unlike in the case where there is no ambiguity, players may come to have different beliefs starting from a common prior, even if they have received exactly the same information, unless the information is common knowledge. [ABSTRACT FROM AUTHOR]

Sporadic Alzheimer’s disease (AD) accounts for a high proportion of AD cases. Therefore, it is of importance to investigate other factors that contribute to the etiology and progression of AD. AD is characterized by decreased cholinergic tone, tau hyperphosphorylation and beta-amyloid (Aβ) accumulation. In addition to the hallmark pathology, other factors have been identified that increase the risk of AD, including stroke. This study examined the combined effects of beta-amyloid administration and unilateral stroke in an animal model of AD. Adult rats were given a sham surgery, bilateral intraventricular infusion of 10 μL of 50 nmol Aβ 25–35 , a unilateral injection of endothelin-1 into the right striatum, or Aβ and endothelin-1 administration in combination. Following a recovery period, rats were tested in the 1-trial place learning variant of the Morris water task followed by an ambiguous discriminative fear-conditioning to context task. After behavioural assessment, rats were euthanized, and representative sections of the medial septum were analyzed for differences in choline-acetyltransferase (ChAT) immunohistochemistry. No differences were observed in spatial working memory, but the combined effect of Aβ and stroke resulted in deficits in the discriminative fear-conditioning to context task. A trend towards decreased ChAT-positive staining in the medial septum was observed. This study indicates that Aβ and stroke in combination produce worse functional consequences than when experienced alone, furthering the concept of AD as a disease with multiple and complex etiologies. [ABSTRACT FROM AUTHOR]

Psycholinguistic research demonstrates that representational distance between meanings influences recognition of ambiguous words. Our goal was to investigate whether the neural correlates of ambiguity are also modulated by representational distance as a function of syntactic similarity (i.e., grammatical class) and meaning dominance. In an event-related fMRI experiment, participants completed a visual lexical decision task that included balanced and unbalanced noun–noun and noun–verb homonyms, unambiguous words, and nonwords. Syntactic similarity effects were observed in left inferior frontal regions, with greater activation for noun–verb than noun–noun homonyms. Meaning dominance effects were observed in left middle and superior temporal regions, with greater activation for balanced than unbalanced homonyms. These findings indicate that the behavioral cost associated with processing ambiguous word meanings, modulated by syntactic similarity and meaning dominance, is reflected in the neural systems underlying ambiguity processing, as frontal and temporal regions are recruited by increased competition as a function of representational distance. [ABSTRACT FROM AUTHOR]

Many have investigated how organisms detect and learn about the patterned sequences of stimuli that they regularly encounter. In some cases, a sequence of stimuli may be structurally ambiguous. That is, more than one rule might be generated in attempts to describe or organize the sequence in a meaningful way. Past studies exploring learning of such sequences have indicated that while subjects can learn about the rules describing such sequences, they often make errors in learning consistent with holding multiple representations of the sequence. Here, we examined the ability of humans and rats to perform runs and trills sequences over the same spatial locations in a pattern production task using a touchscreen (humans) or a circular operant chamber array (rats). One of two signals, presented immediately prior to the start of each trial, indicated which sequence to perform. The results indicated that both species were able to learn to produce runs and trills sequences at levels exceeding chance, which provides additional evidence that humans and rats may hold multiple representations of structurally ambiguous sequences. [ABSTRACT FROM AUTHOR]

We argue that different formulations of hydrodynamics are related to uncertainties in the definitions of local thermodynamic and hydrodynamic variables. We show that this ambiguity can be resolved by viewing different formulations of hydrodynamics as particular "gauge choices" which lead to the same physical behavior of the system. Using the example of bulk viscosity, we show that Bemfica–Disconzi–Noronha–Kovtun (BDNK) and Israel–Stewart hydrodynamics are particular "gauge choices" of this type, related by a well-defined transformation of thermodynamic and hydrodynamic variables. We argue that this gauge ambiguity is necessary to ascertain the causality of stochastic hydrodynamic evolution and conjecture that it could explain the applicability of hydrodynamics outside its expected regime of validity since far from equilibrium and close to equilibrium may be related through transformations of this type. The paper discusses the role of microscopic statistical mechanics within hydrodynamics with arbitrary frame redefinition. [ABSTRACT FROM AUTHOR]

Our research centers the underexamined perspective of Black Americans regarding allyship behaviors and investigates their perceptions and experience of a White ally who confronts a White perpetrator of prejudice. In two experimental studies (N = 1176), we found that Black participants reported higher levels of self-esteem after a White ally confronted a White perpetrator of racial prejudice compared to no confrontation. Additionally, we found that White ally confrontations that signaled intrinsic motivations (i.e., driven by personal values) were perceived as less suspicious in motive than those that signaled extrinsic motivations (i.e., driven by image concerns), which related to more target self-esteem. We discuss implications for research on allyship and confrontation as well as practical considerations. Our results strongly suggest that advantaged group members cannot allow overt prejudice to stand unchecked and should consider the motivations they convey in their actions. [ABSTRACT FROM AUTHOR]

Cross-situational statistical word learning (CSWL) refers to the process whereby participants learn new words by tracking ambiguous word-object co-occurrences across time. This study used event-related potentials to explore the acquisition of novel word meanings via CSWL in healthy adults. After learning to associate novel auditory words (e.g., 'ket') with familiar objects (e.g., sword), participants performed a semantic judgement task where the learned novel words were paired with a familiar word belonging to either the same (e.g., dagger) or a different (e.g., harp) semantic category. As a comparison, the task also included word pairs comprising two familiar words. The analyses revealed that the unrelated novel word pairs elicited a similar N400 to that of the unrelated familiar word pairs, but with a different hemispheric distribution (left hemisphere for novel words, right hemisphere for familiar words). These findings demonstrate rapid meaning acquisition via CSWL, which is reflected at a neurophysiological level. [ABSTRACT FROM AUTHOR]