Computational and Mathematical Organization Theory, 2008
Lau and Murnighan’s faultline theory explains negative effects of demographic diversity on team p... more Lau and Murnighan’s faultline theory explains negative effects of demographic diversity on team performance as consequence of strong demographic faultlines. If demographic differences between group members are correlated across various dimensions, the team is likely to show a “subgroup split” that inhibits communication and effective collaboration between team members. Our paper proposes a rigorous formal and computational reconstruction of the theory. Our model integrates four elementary mechanisms of social interaction, homophily, heterophobia, social influence and rejection into a computational representation of the dynamics of both opinions and social relations in the team. Computational experiments demonstrate that the central claims of faultline theory are consistent with the model. We show furthermore that the model highlights a new structural condition that may give managers a handle to temper the negative effects of strong demographic faultlines. We call this condition the timing of contacts. Computational analyses reveal that negative effects of strong faultlines critically depend on who is when brought in contact with whom in the process of social interactions in the team. More specifically, we demonstrate that faultlines have hardly negative effects when teams are initially split into demographically homogeneous subteams that are merged only when a local consensus has developed.
In this paper we analyze the evolution of solidarity relations between dissimilar actors by means... more In this paper we analyze the evolution of solidarity relations between dissimilar actors by means of a cellular automaton framework. We assume that actors face two types of decisions in the course of an iterated game. First, actors&2018; solidarity decisions constitute mutual support relations between neighbors. Second, by migrating in a two dimensional world, actors select between potential solidarity partners. Moreover, actors are dissimilar with respect to their neediness class, i.e., their need for help. Hegselmann (1996) demonstrated by computer simulation that under these assumptions the behavior of (boundedly) rational egoists may lead to the emergence of a solidarity network that is characterized by class segregation. In the present paper, we explore whether the macro phenomenon of segregation depends on the micro assumption of rationality. We replace Hegselmann&2018;s rational egoist by an adaptive egoist, who takes solidarity and migration decisions on basis of the &2018;law of effect&2019;. A stochastic learning model (e.g., Flache and Macy, 1996) is used to simulate adaptive decision making. Our model of learning behavior, we show, entails the emergence of class segregated solidarity networks. At the same time, however, the evolving networks are considerably more fragile and less extended than those arising amongst rational egoists. While critics of the rational choice approach often argue that rational egoist models tend to underestimate the level of social solidarity, we showed that in this particular analysis relaxing the assumption of rationality may entail the prediction of less rather than more solidarity.
The Journal of Artificial Societies and Social Simulation, 1998
* Abstract The article argues that using cellular automata (CA) is a promising modelling approach... more * Abstract The article argues that using cellular automata (CA) is a promising modelling approach to understand social dynamics. The first section introduces and illustrates the concept of CA. Section 2 gives a short history of CA in the social sciences. Section 3 ...
The Journal of Artificial Societies and Social Simulation, 2001
... Bush Mosteller learning algorithm can generate mutual co-operation in a repeated Prisoner&... more ... Bush Mosteller learning algorithm can generate mutual co-operation in a repeated Prisoner'sdilemma game through "stochastic ... in random sequence to play one round of the support game with every ... The options are evaluated and/or used in a sequential order according to the ...
... existed at equilibrium. That analysis examined tension in dyads for the variety of converged ... more ... existed at equilibrium. That analysis examined tension in dyads for the variety of converged configurations. ... Our bivalent model suggests instead that a social structure is most stable when the network self-... An experimental reexamination of the similarity-attraction ...
Despite fifty years of empirical and theoretical research on social influence, one of the great p... more Despite fifty years of empirical and theoretical research on social influence, one of the great puzzles of social science remains unanswered: How is cultural diversity possible? Axelrod (1997) has proposed a model of cultural dissemination that explains cultural diversity as the consequence of two fundamental social mechanisms - social influence and homophily. Subsequent work has shown that within this framework,
Concerns about models of cultural adaptation as analogs of genetic selection have led cognitive g... more Concerns about models of cultural adaptation as analogs of genetic selection have led cognitive game theorists to explore learning-theoretic specifications. Two prominent examples, the Bush-Mosteller stochastic learning model and the Roth-Erev payoff-matching model, are aligned and integrated as special cases of a general reinforcement learning model. Both models predict stochastic collusion as a backward-looking solution to the problem of cooperation
This study extends previous research that showed how informal social sanctions can backfire when ... more This study extends previous research that showed how informal social sanctions can backfire when members prefer friendship over enforcement of group norms. We use a type of neural network to model the coordination of informal social control in a small group of adaptive agents confronted with a social dilemma. This model incorporates two mechanisms of social influence, informal sanctions and imitation. Both mechanisms vary with the strength of the social tie between source and target. Previous research focused on the effects of social sanctions. Here, we demonstrate a curvilinear effect of imitation on compliance with prosocial norms. Moderate doses of imitation reduce the coordination complexity of self-organized collective action and help the network achieve satisfactory levels of cooperation. High doses, however, undermine the agent-based learning required to find cooperative solutions. Increasing group size also diminishes compliance due to increased complexity, with larger groups requiring more imitation to overcome the coordination problem.
Concerns about models of cultural adaptation as analogs of genetic selection have led cognitive g... more Concerns about models of cultural adaptation as analogs of genetic selection have led cognitive game theorists to explore learning-theoretic specifications. Two prominent examples, the Bush-Mosteller stochastic learning model and the Roth-Erev payoff-matching model, are aligned and integrated as special cases of a general reinforcement learning model. Both models predict stochastic collusion as a backward-looking solution to the problem of cooperation
Computational and Mathematical Organization Theory, 2008
Lau and Murnighan’s faultline theory explains negative effects of demographic diversity on team p... more Lau and Murnighan’s faultline theory explains negative effects of demographic diversity on team performance as consequence of strong demographic faultlines. If demographic differences between group members are correlated across various dimensions, the team is likely to show a “subgroup split” that inhibits communication and effective collaboration between team members. Our paper proposes a rigorous formal and computational reconstruction of the theory. Our model integrates four elementary mechanisms of social interaction, homophily, heterophobia, social influence and rejection into a computational representation of the dynamics of both opinions and social relations in the team. Computational experiments demonstrate that the central claims of faultline theory are consistent with the model. We show furthermore that the model highlights a new structural condition that may give managers a handle to temper the negative effects of strong demographic faultlines. We call this condition the timing of contacts. Computational analyses reveal that negative effects of strong faultlines critically depend on who is when brought in contact with whom in the process of social interactions in the team. More specifically, we demonstrate that faultlines have hardly negative effects when teams are initially split into demographically homogeneous subteams that are merged only when a local consensus has developed.
In this paper we analyze the evolution of solidarity relations between dissimilar actors by means... more In this paper we analyze the evolution of solidarity relations between dissimilar actors by means of a cellular automaton framework. We assume that actors face two types of decisions in the course of an iterated game. First, actors&2018; solidarity decisions constitute mutual support relations between neighbors. Second, by migrating in a two dimensional world, actors select between potential solidarity partners. Moreover, actors are dissimilar with respect to their neediness class, i.e., their need for help. Hegselmann (1996) demonstrated by computer simulation that under these assumptions the behavior of (boundedly) rational egoists may lead to the emergence of a solidarity network that is characterized by class segregation. In the present paper, we explore whether the macro phenomenon of segregation depends on the micro assumption of rationality. We replace Hegselmann&2018;s rational egoist by an adaptive egoist, who takes solidarity and migration decisions on basis of the &2018;law of effect&2019;. A stochastic learning model (e.g., Flache and Macy, 1996) is used to simulate adaptive decision making. Our model of learning behavior, we show, entails the emergence of class segregated solidarity networks. At the same time, however, the evolving networks are considerably more fragile and less extended than those arising amongst rational egoists. While critics of the rational choice approach often argue that rational egoist models tend to underestimate the level of social solidarity, we showed that in this particular analysis relaxing the assumption of rationality may entail the prediction of less rather than more solidarity.
The Journal of Artificial Societies and Social Simulation, 1998
* Abstract The article argues that using cellular automata (CA) is a promising modelling approach... more * Abstract The article argues that using cellular automata (CA) is a promising modelling approach to understand social dynamics. The first section introduces and illustrates the concept of CA. Section 2 gives a short history of CA in the social sciences. Section 3 ...
The Journal of Artificial Societies and Social Simulation, 2001
... Bush Mosteller learning algorithm can generate mutual co-operation in a repeated Prisoner&... more ... Bush Mosteller learning algorithm can generate mutual co-operation in a repeated Prisoner'sdilemma game through "stochastic ... in random sequence to play one round of the support game with every ... The options are evaluated and/or used in a sequential order according to the ...
... existed at equilibrium. That analysis examined tension in dyads for the variety of converged ... more ... existed at equilibrium. That analysis examined tension in dyads for the variety of converged configurations. ... Our bivalent model suggests instead that a social structure is most stable when the network self-... An experimental reexamination of the similarity-attraction ...
Despite fifty years of empirical and theoretical research on social influence, one of the great p... more Despite fifty years of empirical and theoretical research on social influence, one of the great puzzles of social science remains unanswered: How is cultural diversity possible? Axelrod (1997) has proposed a model of cultural dissemination that explains cultural diversity as the consequence of two fundamental social mechanisms - social influence and homophily. Subsequent work has shown that within this framework,
Concerns about models of cultural adaptation as analogs of genetic selection have led cognitive g... more Concerns about models of cultural adaptation as analogs of genetic selection have led cognitive game theorists to explore learning-theoretic specifications. Two prominent examples, the Bush-Mosteller stochastic learning model and the Roth-Erev payoff-matching model, are aligned and integrated as special cases of a general reinforcement learning model. Both models predict stochastic collusion as a backward-looking solution to the problem of cooperation
This study extends previous research that showed how informal social sanctions can backfire when ... more This study extends previous research that showed how informal social sanctions can backfire when members prefer friendship over enforcement of group norms. We use a type of neural network to model the coordination of informal social control in a small group of adaptive agents confronted with a social dilemma. This model incorporates two mechanisms of social influence, informal sanctions and imitation. Both mechanisms vary with the strength of the social tie between source and target. Previous research focused on the effects of social sanctions. Here, we demonstrate a curvilinear effect of imitation on compliance with prosocial norms. Moderate doses of imitation reduce the coordination complexity of self-organized collective action and help the network achieve satisfactory levels of cooperation. High doses, however, undermine the agent-based learning required to find cooperative solutions. Increasing group size also diminishes compliance due to increased complexity, with larger groups requiring more imitation to overcome the coordination problem.
Concerns about models of cultural adaptation as analogs of genetic selection have led cognitive g... more Concerns about models of cultural adaptation as analogs of genetic selection have led cognitive game theorists to explore learning-theoretic specifications. Two prominent examples, the Bush-Mosteller stochastic learning model and the Roth-Erev payoff-matching model, are aligned and integrated as special cases of a general reinforcement learning model. Both models predict stochastic collusion as a backward-looking solution to the problem of cooperation
Uploads
Papers by Andreas Flache