Archive Electronique - Institut Jean Nicod
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1997 research outputs found
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Risk-seeking or impatient? Disentangling variance and time in hazardous behaviors
No full textInternational audienceIndividual observations of risky behaviors present a paradox: individuals who take the most risks in terms of hazards (smoking, speeding, risky sexual behaviors) are also less likely to take risks when it comes to innovation, financial risks or entrepreneurship. Existing theories of risk-preferences do not explain these patterns. From a simple model, we argue that many decisions involving risk have a temporal dimension, and that this dimension is often the main determinant of individual choices. In many real life instances, risk taking amounts to damaging the individual's capital (whether embodied capital, financial capital, social reputation, etc.), which would affect her over a long period of time after the risky decision. In evolutionary terms, the marginal cost of this type of risky behavior depends on the relative importance of the future in the individual's fitness (e.g. her time horizon). Individuals with short time horizons will give less importance to a degradation of their capital because this degradation will be paid effectively for a shorter period of time. This approach explains patterns of behaviors observed across socioeconomic groups and puts forward new approaches to prevent hazardous behaviors such as smoking
Nature and determinants of social actions during a mass shooting
No full textInternational audienceReactions to danger have been depicted as antisocial but research has shown that supportive behaviors (e.g., helping injured others, giving information or reassuring others) prevail in life-threatening circumstances. Why is it so? Previous accounts have put the emphasis on the role of psychosocial factors, such as the maintenance of social norms or the degree of identification between hostages. Other determinants, such as the possibility to escape and distance to danger may also greatly contribute to shaping people's reactions to deadly danger. To examine the role of those specific physical constraints, we interviewed 32 survivors of the attacks at 'Le Bataclan' (on the evening of 13-11-2015 in Paris, France). Consistent with previous findings, supportive behaviors were frequently reported. We also found that impossibility to egress, minimal protection from danger and interpersonal closeness with other crowd members were associated with higher report of supportive behaviors. As we delved into the motives behind reported supportive behaviors, we found that they were mostly described as manifesting cooperative (benefits for both interactants) or altruistic (benefits for other(s) at cost for oneself) tendencies, rather than individualistic (benefits for oneself at cost for other(s)) ones. Our results show that supportive behaviors occur during mass shootings, particularly if people cannot escape, are under minimal protection from the danger, and feel interpersonal closeness with others. Crucially, supportive behaviors underpin a diversity of motives. This last finding calls for a clear-cut distinction between the social strategies people use when exposed to deadly danger, and the psychological motivations underlying them
Ballot Ontology
No full textInternational audienceThe US Presidential Election of 2000 was crucially decided in Florida. And, in Florida, the election might have been decided crucially by the question: is a dimple a hole? “Yes, it is”, so dimpled ballots are valid and ought to be counted. “No it isn’t”, and dimpled ballots must be rejected as invalid. If only one knew the answer! Where were the hole experts when we needed them? Eventually the manual recount was stopped by the Supreme Court. But we did learn something. We learned that even the destiny of a Presidential Election, if not more, might ultimately depend on one’s criteria for identifying holes—not their material surroundings, which everyone could detect, but the holes themselves
The Predictable Evolution of Letter Shapes: An Emergent Script of West Africa Recapitulates Historical Changein Writing Systems
No full textInternational audienceA familiar story about the evolution of alphabets is that individual letters originated in iconic representations of real things. Over time, these naturalistic pictures became simplified into abstract forms. Thus, the iconic ox's head of Egyptian hieroglyphics transformed into the Phoenician and eventually the Roman letter A. In this vein, attempts to theorize the evolution of writing have tended to propose variations on a model of unilinear and unidirectional progression. According to this progressivist formula, pictorial scripts will tend to become more schematic while their systems will target smaller linguistic units. Objections to this theory point to absent, fragmentary, or contrary paleographic evidence, especially for predicted transitions in the underlying grammatical systems of writing. However, the forms of individual signs, such as the letter A, are nonetheless observed to change incrementally over time. We claim that such changes are predictable and that scripts will in fact become visually simpler in the course of their use, a hypothesis regularly confirmed in transmission chain experiments that use graphic stimuli. To test the wider validity of this finding, we turn to the Vai script of Liberia, a syllabic writing system invented in relative isolation by nonliterates in ca. 1833. Unlike the earliest systems of the ancient world, Vai has the advantage of having been systematically documented from its earliest beginnings until the present day. Using established methods for quantifying visual complexity, we find that the Vai script has become increasingly compressed over the first 171 years of its history, complementing earlier claims and partial evidence that similar processes were at work in early writing systems. As predicted, letters simplified to a greater extent when their initial complexity was higher
Choix officiels et choix réels dans les politiques linguistiques israéliennes
No full textInternational audienceL’arabe a perdu son statut de langue officielle en Israël en juillet 2018. C’est l’occasion de s’interroger sur les rapports, complexes, entre le statut officiel d’une langue, la réalité des politiques linguistiques – en particulier dans la sphère éducative – et les pratiques et attentes effectives des locuteurs. Dans le cas qui nous intéresse, la perte du statut de langue officielle ne change pas la situation, déjà ambiguë, dans laquelle se trouvait l’arabe depuis le mandat britannique ; ce qui peut expliquer le peu de mobilisation des premiers intéressés – les arabes israéliens – en opposition à cette perte symbolique de statut. Car, dans les faits, la vitalité de l’arabe israélien dépend de deux facteurs : un bilinguisme asymétrique généralisé (au sens où la population arabe parle hébreu dans une proportion et à un niveau de compétence bien plus élevé que la population juive israélienne ne parle arabe), et des efforts privés non négligeables, en marge du système éducatif, pour favoriser une éducation bilingue réellement symétrique. Dans un pays aussi segmenté, idéologiquement et linguistiquement, qu’Israël, il est intéressant de constater que la vitalité des langues (au-delà de l’hébreu restauré et privilégié depuis les débuts de l’État d’Israël, et de l’arabe, non favorisé mais largement vivant) déborde largement les cadres officiels
Has Money Transformed Our Brains? A Glimpse into Stone-Age Neuroeconomics
No full textInternational audienceMonetary exchanges supported by coins appeared less than 3000 years ago in Lydia. They don't resort to an evolutionary temporal scale of human brain development as determined by long interaction with natural environments. Yet, we can hypothesize, in the light of several behavioral and brain-imaging experiments, that these eminently cultural artifacts, coins, have established specific neural connections with otherwise evolutionary shaped functional brain areas. This is documented by a seemingly fast and automatic processing of coin monetary validity in the posterior fusiform gyrus, a ventral stream area functionally dedicated to the automatic decoding of ecological items such as human faces and food. This type of evidence triggers a discussion on two accounts. It leads us to reconsider how shortterm functional neural adaptations to cultural environments predate long-term neurobiological evolution. Finally, potentially providing new insights on Sahlins' hypotheses about the anthropological emergence of economic activities, it anchors our modern economic behavior and environment into a natural history
Learning and Cognition in Financial Markets: A Paradigm Shift for Agent-Based Models
No full textInternational audienceThe history of research in finance and economics has been widely impacted by the field of Agent-based Computational Economics (ACE). While at the same time being popular among natural science researchers for its proximity to the successful methods of physics and chemistry for example, the field of ACE has also received critics by a part of the social science community for its lack of empiricism. Yet recent trends have shifted the weights of these general arguments and potentially given ACE a whole new range of realism. At the base of these trends are found two present-day major scientific breakthroughs: the steady shift of psychology towards a hard science due to the advances of neuropsychology, and the progress of reinforcement learning due to increasing computational power and big data. We outline here the main lines of a computational research study where each agent would trade by reinforcement learning
Truth-making institutions: From divination, ordeals and oaths to judicial torture and rules of evidence
No full textInternational audienceIn many human societies, truth-making institutions are considered necessary to establish an officially valid or “received” description of some specific situation. These range from divination, oaths, and ordeals to judicial torture or trial by jury. In many cases, these institutions may seem odd or paradoxical, e.g., why would an ordeal reveal a defendant's guilt or innocence? Here we propose to address the questions, why those institutions are considered the source of accepted truth, and why they have recurrent features in many different cultures. Our model is based on two well-documented set of evolved cognitive mechanisms. One is epistemic vigilance, the set of cognitive processes that help us evaluate the quality of communicated information we receive. We show how our epistemic intuitions account for otherwise puzzling aspects of divination, oaths, and ordeals. The other set of mechanisms consists in human capacities for coalition building and the recruitment of social support, which explains how truth-making institutions can be strategically used by individuals to influence mutual knowledge for their own interests. Taken together, these mechanisms explain the kinds of institutions found in small-scale societies (oaths, ordeals, divination), as well as the emergence of different institutions (laws of evidence, judicial torture, trial by jury) in large-scale and modern societies
Musical Meaning within Super Semantics *
No full textInternational audienceAs part of a recent attempt to extend the methods of formal semantics beyond language ('Super Semantics'), it has been claimed that music has an abstract truth-conditional semantics, albeit one that has more in common with iconic semantics than with standard compositional semantics (Schlenker 2017, 2019a, b). After summarizing this approach and addressing a common objection (here due to Leonard Bernstein), we argue that music semantics should be enriched in three directions by incorporating insights of other areas of Super Semantics. First, it has been claimed by Abusch 2013 that visual narratives make use of discourse referents akin to those we find in language. We argue that a similar conclusion extends to music, and we highlight it by investigating ways in which orchestration and dance may make cross-referential dependencies more explicit. Second, we show that by bringing music semantics closer to the semantics of visual narratives, we can give an account of the semantics of mixed visual and musical sequences. Third, it has been claimed that co-speech gestures trigger characteristic conditionalized presuppositions, called 'cosuppositions', and that their semantic status derives from their parasitic character relative to words (Schlenker 2018a,b). We argue that the same conclusion extends to some instances of film and cartoon music: it may trigger cosuppositions that can be revealed by embedding film excerpts or gifs in sentences so as to test presupposition projection. We further argue that under special discourse conditions (pertaining to certain Questions under Discussion), pro-speech gestures and pro-speech music alike can trigger cosuppositions as well. These results suggest that new insights can be gained not just by extending the methods of semantics to new objects, but also by drawing new connections among them