Tipping and the Dynamics of Segregation

In a classic paper, Schelling (1971) showed that extreme segregation can arise from social interactions in white preferences: once the minority share in a neighborhood exceeds a critical "tipping point," all the whites leave. We use regression discontinuity methods and Census tract data from 1970 through 2000 to test for discontinuities in the dynamics of neighborhood racial composition. White population flows exhibit tipping-like behavior in most cities, with a distribution of tipping points ranging from 5% to 20% minority share. The estimated discontinuities are robust to controls for a wide variety of neighborhood characteristics, and are as strong in the suburbs as in tracts close to high-minority neighborhoods, ruling out the main alternative explanations for apparent tipping behavior. In contrast to white population flows, there is no systematic evidence that rents or housing prices exhibit non-linearities around the tipping point. Finally, we relate the location of the estimated tipping points in different cities to measures of the racial attitudes of whites, and find that cities with more tolerant whites have higher tipping points.

A dynamical systems model of unorganised segregation

We consider Schelling's bounded neighbourhood model (BNM) of unorganised segregation of two populations from the perspective of modern dynamical systems theory. We derive a Schelling dynamical system and carry out a complete quantitative analysis of the system for the case of a linear tolerance schedule in both populations. In doing so, we recover and generalise Schelling's qualitative results. For the case of unlimited population movement, we derive exact formulae for regions in parameter space where stable integrated population mixes can occur. We show how neighbourhood tipping can be adequately explained in terms of basins of attraction. For the case of limiting population movement, we derive exact criteria for the occurrence of new population mixes and identify the stable cases. We show how to apply our methodology to nonlinear tolerance schedules, illustrating our approach with numerical simulations. We associate each term in our Schelling dynamical system with a social meaning. In particular we show that the dynamics of one population in the presence of another can be summarised as follows {rate of population change} = {intrinsic popularity of neighbourhood} - {finite size of neighbourhood} - {presence of other population} By approaching the dynamics from this perspective, we have a complementary approach to that of the tolerance schedule.Comment: 17 pages (inc references), 9 figure

Strategic behavior in Schelling dynamics: A new result and experimental evidence

In this paper we experimentally test Schelling’s (1971) segregation model and confirm the striking result of segregation. In addition, we extend Schelling’s model theoretically by adding strategic behavior and moving costs. We obtain a unique subgame perfect equilibrium in which rational agents facing moving costs may find it optimal not to move (anticipating other participants’ movements). This equilibrium is far for full segregation. We run experiments for this extended Schelling model. We find that the percentage of strategic players dramatically increases with the cost of moving and that the degree of segregation depends on the distribution of rational subjects.Subgame perfect equilibrium, segregation, experimental games

An interview with Thomas C. Schelling: Interpretation of game theory and the checkerboard model

This note is mainly based on a short interview with Thomas C. Schelling (TCS), who shared the Nobel Prize with Robert J. Aumann in 2005. The interview took place on 06.03.2001 at University of Maryland, College Park, USA. It consists of two parts. The first part is about his interpretation of game theory, particularly about the use of game- theoretic models in explaining the origin and maintenance of conventions, and norms. The second part is on the origin of Schelling’s influential checkerboard model of residential segregation, particularly about his approach to modeling social phenomena exemplified by this model. The note ends with some concluding remarks. Citation: Aydinonat, N. Emrah, (2005) 'An interview with Thomas C. Schelling: Interpretation of game theory and the checkerboard model,' Economics Bulletin, Vol. 2 no. 2 pp. 1-7.Thomas Schelling, game theory, checkerboard model

An interview with Thomas C. Schelling: Interpretation of game theory and the checkerboard model

This note is mainly based on a short interview with Thomas C. Schelling (TCS), who shared the Nobel Prize with Robert J. Aumann in 2005. The interview took place on 06.03.2001 at University of Maryland, College Park, USA. It consists of two parts. The first part is about his interpretation of game theory, particularly about the use of game-theoretic models in explaining the origin and maintenance of conventions, and norms. The second part is on the origin of Schelling's influential checkerboard model of residential segregation, particularly about his approach to modeling social phenomena exemplified by this model. The note ends with some concluding remarks.checkerboard model

Black/white segregation in the Eighth District: a look at the dynamics

Demography ; Federal Reserve District, 8th

Dynamic models of residential ségrégation: an analytical solution

We propose an analytical resolution of Schelling segregation model for a general class of utility functions. Using evolutionary game theory, we provide conditions under which a potential function, which characterizes the global configuration of the city and is maximized in the stationary state, exists. We use this potential function to analyze the outcome of the model for three utility functions corresponding to different degrees of preference for mixed neighborhoods. Schelling original utility function is shown to drive segregation at the expense of collective utility. If agents have a strict preference for mixed neighborhoods but still prefer being in the majority versus in the minority, the model converges to perfectly segregated configurations, which clearly diverge from the social optimum. Departing from earlier literature, these conclusions are based on analytical results. These results pave the way to the analysis of many structures of preferences, for instance those based on empirical findings concerning racial preferences. As a by-product, our analysis builds a bridge between Schelling model and the Duncan and Duncan segregation index.Residential segregation ; Schelling ; dynamic model ; potential function ; social preferences

Neighbourhood mobility in context : household moves and changing neighbourhoods in the Netherlands

Although high levels of population mobility are often viewed as a problem at the neighbourhood level we know relatively little about what makes some neighbourhoods more mobile than others. The main question in this paper is to what extent differences in out-mobility between neighbourhoods can be explained by differences in the share of mobile residents, or whether other neighbourhood characteristics also play a role. To answer this question we focus on the effects of the socioeconomic status and ethnic composition of neighbourhoods and on neighbourhood change. Using data from the Netherlands population registration system and the Housing Demand Survey we model population mobility both at individual and at neighbourhood levels. The aggregate results show that the composition of the housing stock and of the neighbourhood population explain most of the variation in levels of neighbourhood out-mobility. At the same time, although ethnic minority groups in the Netherlands are shown to be relatively immobile, neighbourhoods with higher concentrations of ethnic minority residents have the highest population turnovers. The individual-level models show that people living in neighbourhoods which experience an increase in the percentage of ethnic minorities are more likely to move, except when they belong to an ethnic minority group themselves. The evidence suggests that 'white flight' and 'socio-economic flight' are important factors in neighbourhood change.PostprintPeer reviewe

Segregation and Strategic Neighborhood Interaction

We introduce social interactions into the Schelling model of residential choice. These social interactions take the form of a Prisoner's Dilemma game played with neighbors. First, we study the Schelling model over a wide range of utility functions and then proceed to study a spatial Prisoner's Dilemma model. These models provide a benchmark for studying a combined model with preferences over like-typed neighbors and payoffs in the spatial Prisoner's Dilemma game. We study this combined model both analytically and using agent-based simulations. We find that the presence of these additional social interactions may increase or decrease segregation compared to the standard Schelling model. If the social interactions result in cooperation then segregation is reduced, otherwise it is increased.Schelling Tipping Model, Spatial Prisoner's Dilemma, Cooperation, Segregation