Experimental games on networks: Underpinnings of behavior and equilibrium selection

Date: 2014-04
By: Gary Charness
Francesco Feri
Miguel A. Meléndez-Jiménez
Matthias Sutter
URL: http://d.repec.org/n?u=RePEc:inn:wpaper:2014-14&r=net
In this paper, we describe a series of laboratory experiments that implement specific examples of a more general network structure and we examine equilibrium selection. Specifically, actions are either strategic substitutes or strategic complements, and participants have either complete or incomplete information about the structure of a random network. Since economic environments typically have a considerable degree of complementarity or substitutability, this framework applies to a wide variety of settings. The degree of equilibrium play is striking, in particular with incomplete information. Behavior closely resembles the theoretical equilibrium whenever this is unique; when there are multiple equilibria, general features of networks, such as connectivity, clustering, and the degree of the players, help to predict informed behavior in the lab. People appear to be strongly attracted to maximizing aggregate payoffs (social efficiency), but there are forces that moderate this attraction: 1) people seem content with (in the aggregate) capturing only the lion’s share of the efficient profits in exchange for reduced exposure to loss, and 2) uncertainty about the network structure makes it considerably more difficult to coordinate on a demanding, but efficient, equilibrium that is typically implemented with complete information.
Keywords: Random networks, Incomplete information, Connectivity, Clustering, Strategic substitutes, Strategic complements, Experiment
JEL: C71 C91 D03 D85

Experimental Games on Networks: Underpinnings of Behavior and Equilibrium Selection

Date: 2014-04
By: Charness, Gary (University of California, Santa Barbara)
Feri, Francesco (University of Innsbruck)
Meléndez-Jiménez, Miguel A. (University of Malaga)
Sutter, Matthias (European University Institute)
URL: http://d.repec.org/n?u=RePEc:iza:izadps:dp8104&r=net
In this paper, we describe a series of laboratory experiments that implement specific examples of a more general network structure and we examine equilibrium selection. Specifically, actions are either strategic substitutes or strategic complements, and participants have either complete or incomplete information about the structure of a random network. Since economic environments typically have a considerable degree of complementarity or substitutability, this framework applies to a wide variety of settings. The degree of equilibrium play is striking, in particular with incomplete information. Behavior closely resembles the theoretical equilibrium whenever this is unique; when there are multiple equilibria, general features of networks, such as connectivity, clustering, and the degree of the players, help to predict informed behavior in the lab. People appear to be strongly attracted to maximizing aggregate payoffs (social efficiency), but there are forces that moderate this attraction: 1) people seem content with (in the aggregate) capturing only the lion’s share of the efficient profits in exchange for reduced exposure to loss, and 2) uncertainty about the network structure makes it considerably more difficult to coordinate on a demanding, but efficient, equilibrium that is typically implemented with complete information.
Keywords: random networks, incomplete information, connectivity, clustering, strategic substitutes, strategic complements, experiment
JEL: C71 C91 D03 D85

Facts and Figuring: An Experimental Investigation of Network Structure and Performance in Information and Solution Spaces

Date: 2014-03
By: Jesse Shore (Boston University – Department of Information Systems)
Ethan Bernstein (Harvard Business School, Organizational Behavior Unit)
David Lazer (Harvard University – Harvard Kennedy School (HKS))
URL: http://d.repec.org/n?u=RePEc:hbs:wpaper:14-075&r=net
Using data from a novel laboratory experiment on complex problem solving in which we varied the network structure of 16-person organizations, we investigate how an organization’s network structure shapes performance in problem-solving tasks. Problem solving, we argue, involves both search for information and search for solutions. Our results show that the effect of network structure is opposite for these two important and complementary forms of search. Dense clustering encourages members of a network to generate more diverse information, but discourages them from generating diverse theories: in the language of March (1991), clustering promotes exploration in information space, but decreases exploration in solution space. Previous research, generally focusing on only one of those two spaces at a time, has produced inconsistent conclusions about the value of network clustering. By adopting an experimental platform on which information was measured separately from solutions, we were able to reconcile past contradictions and clarify the effects of network clustering on problem-solving performance. The finding both provides a sharper tool for structuring organizations for knowledge work and reveals the challenges inherent in manipulating network structure to enhance performance, as the communication structure that helps one antecedent of successful problem solving may harm the other.
Keywords: networks, experiments, clustering, problem solving, exploration and exploitation, knowledge, information, communication, search

Experimental Games on Networks: Underpinnings of Behavior and Equilibrium Selection

Date: 2013-07-22
By: Charness, Gary
Feri, Francesco
Meléndez-Jiménez, Miguel A
Sutter, Matthias
URL: http://d.repec.org/n?u=RePEc:cdl:ucsbec:qt6m0584qv&r=net
Keywords: Social and Behavioral Sciences

Abstract.

We study behavior and equilibrium selection in network games. We conduct a series of experiments (with 580 participants) in which actions are either strategic substitutes or strategic complements, and participants have either complete or incomplete information about the structure of a random network. In our initial set of experiments on 5-person networks, we find a great deal of qualitative and quantitative support for the theoretical predictions of the Galeotti, Goyal, Jackson, Vega-Redondo, and Yariv (2010) model. The degree of equilibrium play is striking, in particular with incomplete information. There are intriguing patterns in our data, such as a taste for positive payoffs (but also security) when this supports the choice of one of the potential equilibria in a complete-information setting. To shed further light on the underpinnings of behavior and equilibrium selection in the laboratory, we study three more 5-person networks and test robustness by conducting sessions with three 20-person networks. Overall, we see strong evidence that choices and the equilibrium played depend on one’s degree and the connectivity of the network, and suggestive evidence that choices also depend on the clustering in the network.
JEL Codes: C71, C91, D03, D85
Keywords: Random networks; Incomplete information; Connectivity; Clustering; Strategic substitutes; Strategic complements; Experiment