Mine and Thine: The Territorial Foundations of Human Property

Research shows that many animal species have morphological and cognitive adaptations for fighting with others to gain resources, but it remains unclear how humans make fighting decisions. Non-human animals often adaptively calibrate fighting behavior to ecological variables such as resource quantity and whether the resource is distributed uniformly or clustered in patches. Also, many species use strategies to reduce fighting costs such as resolving disputes based on power asymmetries or conventions. Here we show that humans apply an ownership convention in response to the problem of severe fighting. We designed a virtual environment where ten participants, acting as avatars, could forage and fight for electronic food items (convertible to cash). In the patchy condition, we observed an ownership convention—the avatar who arrives first is more likely to win—but in the uniform condition, where severe fighting is rare, the ownership convention is absent.

Differentiating the hospital supply chain for enhanced performance

Thesis (M. Eng. in Logistics)--Massachusetts Institute of Technology, Engineering Systems Division, 2005.Includes bibliographical references (leaves 51-52).This thesis determines how to design the supply chain policies in a hospital for the wide array of products that exist there. This research was done through interviewing staff and analyzing data of two hospitals implementing automated point of use systems. This thesis argues that a hospital needs to implement more than one supply chain policy in order to achieve its objective of maximizing patient care while avoiding prohibitive costs. The research further proposes that a hospital should develop its supply chain for a specific product based on that product's unit cost, demand, variability, physical size, and criticality. The research analyzes demand data from two hospitals and demonstrates that hospital demand can be modeled using a variation of Croston's method for intermittent demand. This fact was used to generate an appropriate s, Q inventory policy that can be adjusted to fit any product and supply chain policy implemented within the hospital. Under simulation, the proposed inventory policy outperformed existing policies by over 50%. This research further argues current aggregate and "one-size-fits-all" strategies are inappropriate in a hospital and discusses the importance for hospitals to add physical size and criticality attributes to their product master files as these will enable further supply chain enhancements.by Derek T. DeScioli.M.Eng.in Logistic

The psychology of coordination and common knowledge.

Research on human cooperation has concentrated on the puzzle of altruism, in which one actor incurs a cost to benefit another, and the psychology of reciprocity, which evolved to solve this problem. We examine the complementary puzzle of mutualism, in which actors can benefit each other simultaneously, and the psychology of coordination, which ensures such benefits. Coordination is facilitated by common knowledge—the recursive belief state in which A knows X, B knows X, A knows that B knows X, B knows that A knows X, ad infinitum. We test whether people are sensitive to common knowledge when deciding whether to engage in risky coordination. Participants decided between working alone for a certain profit and working together for a potentially higher profit that they would receive only if their partner made the same choice. Results showed that more participants attempted risky coordination when they and their prospective partner had common knowledge of the payoffs (broadcasted over a loudspeaker) than when they had only shared knowledge (conveyed to both by a messenger) or primary knowledge (revealed to each partner separately). These results confirm the hypothesis that people represent common knowledge as a distinct cognitive category that licenses them to coordinate with others for mutual gain. We discuss how this hypothesis can provide a unified explanation for diverse phenomena in human social life, including recursive mentalizing, performative speech acts, public assemblies and protests, and self-conscious emotional expressions.Psycholog

The Means/Side-Effect Distinction in Moral Cognition: A Meta-Analysis

Experimental research suggests that people draw a moral distinction between bad outcomes brought about as a means versus a side effect (or byproduct). Such findings have informed multiple psychological and philosophical debates about moral cognition, including its computational structure, its sensitivity to the famous Doctrine of Double Effect, its reliability, and its status as a universal and innate mental module akin to universal grammar. But some studies have failed to replicate the means/byproduct effect especially in the absence of other factors, such as personal contact. So we aimed to determine how robust the means/byproduct effect is by conducting a meta-analysis of both published and unpublished studies (k = 101; 24,058 participants). We found that while there is an overall small difference between moral judgments of means and byproducts (standardized mean difference = 0.87, 95% CI 0.67 – 1.06; standardized mean change = 0.57, 95% CI 0.44 – 0.69; log odds ratio = 1.59, 95% CI 1.15 – 2.02), the mean effect size is primarily moderated by whether the outcome is brought about by personal contact, which typically involves the use of personal force

Evaluating Arguments From the Reaction of the Audience

In studying how lay people evaluate arguments, psychologists have typically focused on logical form and content. This emphasis has masked an important yet underappreciated aspect of everyday argument evaluation: social cues to argument strength. Here we focus on the ways in which observers evaluate arguments by the reaction they evoke in an audience. This type of evaluation is likely to occur either when people are not privy to the content of the arguments or when they are not expert enough to appropriately evaluate it. Four experiments explore cues that participants might take into account in evaluating arguments from the reaction of the audience. They demonstrate that participants can use audience motivation, expertise, and size as clues to argument quality. By contrast we find no evidence that participants take audience diversity into account

Distinguishing Family from Friends

Kinship and friendship are key human relationships. Increasingly, data suggest that people are not less altruistic toward friends than close kin. Some accounts suggest that psychologically we do not distinguish between them; countering this is evidence that kinship provides a unique explanatory factor. Using the Implicit Association Test, we examined how people implicitly think about close friends versus close kin in three contexts. In Experiment 1, we examined generic attitudinal dispositions toward friends and family. In Experiment 2, attitude similarity as a marker of family and friends was examined, and in Experiments 3 and 4, strength of in-group membership for family and friends was examined. Findings show that differences exist in implicit cognitive associations toward family and friends. There is some evidence that people hold more positive general dispositions toward friends, associate attitude similarity more with friends, consider family as more representative of the in-group than friends, but see friends as more in-group than distant kin

Is the Relationship Between Pathogen Avoidance and Ideological Conservatism Explained by Sexual Strategies?

Multiple recent studies report that measures of pathogen avoidance (e.g., disgust sensitivity) correlate with political ideology. This relationship has been interpreted as suggesting that certain political views (specifically, those views that are categorized as socially conservative) function to mitigate the pathogen threats posed either by intergroup interactions or by departures from traditional societal norms, which sometimes evolve culturally for anti-pathogen functions. We propose and test the alternative hypothesis that pathogen avoidance relates to conservatism indirectly via sexual strategies (e.g., relatively monogamous versus relatively promiscuous). Specifically, we argue that individuals who are more invested in avoiding pathogens follow a more monogamous mating strategy to mitigate against pathogens transmitted during sexual contact, and individuals following a more monogamous mating strategy adopt socially conservative political ideologies to support their reproductive interests. Results from three studies ( N's = 819, 238, and 248) using multiple measures of pathogen avoidance, sexual strategies, and ideology support this account, with sexual strategies fully mediating the relationship between measures of pathogen avoidance and conservatism in each study