Game Theoretical Interactions of Moving Agents

Game theory has been one of the most successful quantitative concepts to describe social interactions, their strategical aspects, and outcomes. Among the payoff matrix quantifying the result of a social interaction, the interaction conditions have been varied, such as the number of repeated interactions, the number of interaction partners, the possibility to punish defective behavior etc. While an extension to spatial interactions has been considered early on such as in the "game of life", recent studies have focussed on effects of the structure of social interaction networks. However, the possibility of individuals to move and, thereby, evade areas with a high level of defection, and to seek areas with a high level of cooperation, has not been fully explored so far. This contribution presents a model combining game theoretical interactions with success-driven motion in space, and studies the consequences that this may have for the degree of cooperation and the spatio-temporal dynamics in the population. It is demonstrated that the combination of game theoretical interactions with motion gives rise to many self-organized behavioral patterns on an aggregate level, which can explain a variety of empirically observed social behaviors

Growing Income Inequality Threatens American Education

The first of two articles in consecutive months describes the origins and nature of growing income inequality, and some of its consequences for American children. It documents the increased family income inequality that's occurred over the past 40 years and shows that the increased income disparity has been more than matched by an expanding gap between the amounts of money that low- and high-income parents spend on enrichment activities for their children. It also shows that the growth in income inequality has been accompanied by increasing gaps in academic achievement. The article draws from the first part of the author's recent book, Restoring Opportunity: The Crisis of Inequality and the Challenge for American Education (Harvard Education Press and the Russell Sage Foundation, 2014). The second part to the series, also drawn from Restoring Opportunity, describes ideas based on proven policy approaches that will enable the country to make progress on the enormous task of restoring the educational opportunities that children from low-income families need if they are to lead productive and fulfilling lives. © 2014

Mapping the multiple contexts of racial isolation: the case of Long Street, Cape Town

This article explores the idea that racial segregation is a process operating across a range of scales of social life. The focus is upon how segregation unfolds and is (re)produced at what can be termed the ‘micro-ecological’ scale — that is, in the everyday, interpersonal interactions between people in informal settings. To illustrate this argument, a case study is presented of relations in the night-time economy of Long Street, Cape Town. It is shown how such relations comprise micro-ecological practices of contact and isolation that occur at levels of resolution seldom captured by segregation research