Food seeking and food sharing under uncertainty.

We propose an elaboration of Anselme and Güntürkün's research that considers individuals' foraging behavior as part of group efforts to cope with uncertainty. We discuss different possibilities for the interaction between individual and group mechanisms for risk reduction in uncertain environments, and we raise some open questions for future research.

Sensitivity to fairness and intentions of others in the ultimatum game in patients with ventromedial prefontal lesions.

This study aimed to examine the relationship between perspective-taking and impaired decision-making in patients with ventromedial prefrontal (VM) lesions, using the Ultimatum Game (UG). In the UG, two players split a sum of money and one player proposes a division while the other can accept or reject this. Eight patients with VM damage and 18 healthy controls participated as responders in a modified version of the UG, in which identical offers can generate different rejection rates depending on the other offers available to the proposer. Participants had to either accept or reject offers of 2:8 NIS (2NIS for them and 8 NIS for the proposer), which were paired with one of four different possible offers (5:5, 4:6, 2:8, 8:2). Results indicate that the controls more often rejected offers of 2:8 when the alternative was 4:6 (a greedy alternative) than when the alternative was 5:5 (fair alternative), whereas the VM patients showed the opposite pattern of decision-making. Additionally, the overall rejection rates were higher in patients as compared to controls. Furthermore, scores on a perspective-taking scale were negatively correlated with rejection rates in the patient group, suggesting that perspective-taking deficits may account for impaired decision-making in VM patients.

On gamesmen and fair men: explaining fairness in non-cooperative bargaining games.

Experiments on bargaining games have repeatedly shown that subjects fail to use backward induction, and that they only rarely make demands in accordance with the subgame perfect equilibrium. In a recent paper, we proposed an alternative model, termed 'economic harmony' in which we modified the individual's utility by defining it as a function of the ratio between the actual and aspired pay-offs. We also abandoned the notion of equilibrium, in favour of a new notion of 'harmony', defined as the intersection of strategies, at which all players are equally satisfied. We showed that the proposed model yields excellent predictions of offers in the ultimatum game, and requests in the sequential common pool resource dilemma game. Strikingly, the predicted demand in the ultimatum game is equal to the famous Golden Ratio (approx. 0.62 of the entire pie). The same prediction was recently derived independently by Schuster (Schuster 2017. Sci. Rep.7, 5642). In this paper, we extend the solution to bargaining games with alternating offers. We show that the derived solution predicts the opening demands reported in several experiments, on games with equal and unequal discount factors and game horizons. Our solution also predicts several unexplained findings, including the puzzling 'disadvantageous counter-offers', and the insensitivity of opening demands to variations in the players' discount factors, and game horizon. Strikingly, we find that the predicted opening demand in the alternating offers game is also equal to the Golden Ratio.

Perception of the minority's collective identity and voting behavior: the case of the Palestinians in Israel.

The author investigated how Palestinian (n = 130) and Jewish (n = 153) Israeli university students perceived the collective identity of the Palestinian minority in Israel. The Palestinian and Jewish respondents perceived the "identity space" of the minority as linear, or bipolar, with 1 pole defined by the national (Palestinian) identity and the other defined by the civic (Israeli) label. The Palestinian respondents defined their collective identity in national (Palestinian, Arab) and integrative (Israeli-Palestinian) terms; the Jewish respondents perceived the minority's identity as integrative (Israeli-Palestinian). Different political outlooks among Palestinian respondents were related to their identification with the civic (Israeli) identity but not to their identification with the national (Palestinian) identity. In contrast, different political outlooks among Jewish respondents were related to their inclusion, or exclusion, of the national (Palestinian) component in their definition of the minority's identity. Implications of the results are discussed in terms of a minority acculturation model (J. Berry, J. Trimble, & E. Olmedo, 1986).