I study a model of group identification in which individuals' opinions as to the membership of a group are aggregated to form a list of group members. Potential aggregation rules are studied through the axiomatic approach. I introduce two axioms, meet separability and join separability, each of...

While a large social-choice-theoretic literature discusses the aggregation of individual judgments into collective ones, there is relatively little formal work on the transformation of individual judgments in group deliberation. I develop a model of judgment transformation and prove a baseline...

Party activists wish to (i) advocate the best policy and yet (ii) unify behind a common party line. An activist's understanding of his environment is based on the speeches of party leaders. A leader's influence, measured by the weight placed on her speech, increases with her judgement on policy...

We study the effects of individual and collective ministerial performance on the length of time a minister serves in British government from 1945-97, using the number of resignation calls for a minister as an individual performance indicator and the cumulative number of such calls as an...

Voters have strong incentives to increase their influence by trading votes, a practice indeed believed to be common. But is vote trading welfare-improving or welfare-decreasing? We review the theoretical literature and, when available, its related experimental tests. We begin with the analysis...

The Shapley-Shubik index was designed to evaluate the power distribution in committee systems drawing binary decisions and is one of the most established power indices. It was generalized to decisions with more than two levels of approval in the input and output. In the limit we have a continuum...

Which social decisions are intuitive? Which are deliberative? The dual-process approach to human sociality has emerged in the last decades as a vibrant and exciting area of research. Here, I review the existing literature on the cognitive basis of cooperation, altruism, honesty, positive and...

Gender differences in human behaviour have attracted generations of social scientists, who have explored whether males and females act differently in domains involving competition, risk taking, cooperation, altruism, honesty, as well as many others. Yet, little is known about gender differences...

Many societies today are experiencing growing inequality in terms of wealth, income, health, education, resources or opportunities, trends that have negative effects upon well-being, trust, and motivation. We investigated whether inequalities –– particularly those perceived as fair ––...

Many situations require people to act quickly and are characterized by asymmetric information. Since asymmetric information makes people tempted to misreport their private information for their own benefit, it is of primary importance to understand whether time pressure affects honest behavior....