Erik O. Kimbrough

• Ph.D. Computational Sciences
• Professor at Chapman University

In laboratory asset markets, subjects trade shares of a firm whose profits in a linked product market determine dividends. Treatments vary whether dividend information is revealed once per period or in real-time and whether the firm is controlled by a profit-maximizing robot or human subject. The latter variation induces uncertainty about firm beha...

We explore the idea that prosocial behavior in experimental games is driven by social norms imported into the laboratory. Under this view, differences in behavior across subjects is driven by heterogeneity in sensitivity to social norms. We introduce an incentivized method of eliciting individual norm-sensitivity, and we show how it relates to play...

Spiteful, antisocial behavior may undermine the moral and institutional fabric of society, producing disorder, fear, and mistrust. Previous research demonstrates the willingness of individuals to harm others, but little is understood about how far people are willing to go in being spiteful (relative to how far they could have gone) or their consist...

Conflict and competition often impose costs on both winners and losers, and conflicting parties may prefer to resolve the dispute before it occurs. The equilibrium of a conflict game with side-payments predicts that with binding offers, proposers make and responders accept side-payments, generating settlements that strongly favor proposers. When si...

This laboratory experiment explores the extent to which impersonal exchange emerges from personal exchange with opportunities for long-distance trade. We design a three-commodity production and exchange economy in which agents in three geographically separated villages must develop multilateral exchange networks to import a good only available abro...

Recent research has shown how norms shape political and economic decision-making. Much of this work assumes that a single norm influences the behavior of all people, but in fact, many situations are characterized by the existence of competing normative viewpoints. We apply a method for measuring belief in the simultaneous existence of multiple norm...

This article provides an introduction to and overview of the articles in the PNAS Nexus Special Feature on Polarization and Trust.

Norm-based accounts of social behavior in economics typically reflect tradeoffs between maximization of own consumption utility and conformity to social norms. Theories of norm-following tend to assume that there exists a single, stable, commonly known injunctive social norm for a given choice setting and that each person has a stable propensity to...

We measure normative expectations in dictator games and naturally occurring vignettes using the norm-elicitation procedure based on coordination games (Krupka & Weber, 2013). We test a five-item scale, allowing subjects to report "neither socially appropriate nor inappropriate" behavior. In principle, this category is better suited to identify hete...

The rapid growth of cultural evolutionary science, its expansion into numerous fields, its use of diverse methods, and several conceptual problems have outpaced corollary developments in theory and philosophy of science. This has led to concern, exemplified in results from a recent survey conducted with members of the Cultural Evolution Society, th...

We analyze and compare three methods of measuring norms: the Krupka and Weber (KW) coordination game, the two-step approach by Bicchieri and Xiao (BX), and a novel Binarized Scoring Method (BSM) we introduce that elicits the full distribution of normative beliefs. We test their effectiveness in two distinctive ways. First, we compare the fit and pr...

Bølstad and Dinas (2017) propose a model of spatial voting, based on social identity theory, that suggests supporting a candidate/policy on the other side of the ideological spectrum has a disutility that is not accounted for by common spatial models. Unfortunately, the data they use cannot speak directly to whether the disutility arises because in...

The MECHANISMS study investigates how social norms for adolescent smoking and vaping are transmitted through school friendship networks, and is the first study to use behavioral economics methodology to assess smoking-related social norms. Here, we investigate the effects of selection homophily (the tendency to form friendships with similar peers)...

Little is known about the personality and cognitive traits that shape adolescents’ sensitivity to social norms. Further, few studies have harnessed novel empirical tools to elicit sensitivity to social norms among adolescent populations. This paper examines the association between sensitivity to norms and various personality and cognitive traits us...

We attempt to replicate a seminal paper that offered support for the rational expectations hypothesis and reported evidence that markets with certain features aggregate dispersed information. The original results are based on only a few observations, and our attempt to replicate the key findings with an appropriately powered experiment largely fail...

How should ideology be understood, and should we be concerned if Americans lack it? Combining widely used survey questions with an incentivized coordination game, we separately measure individuals’ own policy preferences and their knowledge of what other ideological group members expect them to believe. This allows us to distinguish knowledge of id...

This article introduces a simple application of contest theory that neatly captures how Boulding’s ‘loss of strength gradient’ determines the geographic extent of territory. We focus on the ‘supply side’ of territorial conflict, showing how the costs of initiating and escalating conflict over spatially dispersed resources shape the nature and scope...

Background: Many adolescent smoking prevention programs target social norms, typically evaluated with self-report, susceptible to social desirability bias. An alternative approach with limited application in public health is to use experimental norms elicitation methods. Methods: Using the Mechanisms of Networks and Norms Influence on Smoking in Sc...

Background/purpose: The MECHANISMS study targets smoking prevention for 12-13 year olds in Northern Ireland and Bogotá, and investigates the mechanisms through which social norms for smoking and vaping are transmitted through school social networks. We aimed to provide a broad overview of homophily and peer influence effects for norms and other smo...

Evidence from psychology and marketing suggests that those who make a “precise” first offer in bargaining get a better deal than those who make a “round” first offer. We report on a series of experiments designed to test for and improve our understanding of the “precise first offer” (PFO) effect in bargaining and whether it likely reflects rational...

When deciding whether to support a political candidate, policy or cause, individuals are observed to prioritize the expression of their political identities. They even knowingly incur personal costs (a lower wage, strained family relations) to do so. We argue that viewing political identities as social identities that impart norms on who or what on...

Many adolescent smoking prevention programmes target social norms, typically evaluated with self-report, susceptible to social desirability bias. An alternative approach with little application in public health are experimental norms elicitation methods. Using the Mechanisms of Networks and Norms Influence on Smoking in Schools (MECHANISMS) study b...

This proof of concept study harnesses novel transdisciplinary insights to contrast two school-based smoking prevention interventions among adolescents in the UK and Colombia. We compare schools in these locations because smoking rates and norms are different, in order to better understand social norms based mechanisms of action related to smoking....

Auction winners sometimes suffer a “bidder’s curse”, paying more for an item at auction than the fixed price charged for an identical item by other sellers. This seemingly irrational behavior is puzzling because the information necessary to avoid overpaying would appear to be readily available to bidders, yet they seem to ignore it. To understand t...

Ethnic and kinship ties have long been viewed as potential catalysts for favoritism, and hence corruption. In experiments conducted in three countries, we recruit siblings, coethnics and strangers and vary the relationship(s) between the players of a game to observe how kin and ethnic ties influence the willingness of two players to benefit one ano...

Evidence from psychology and marketing suggests that those who make a "precise" first offer in bargaining get a better deal than those who make a "round" first offer. We report on a series of experiments designed to test for and improve our understanding of the "precise first offer" (PFO) effect in bargaining and whether it likely reflects rational...

When making political and economic decisions (e.g., voting, donating money to a cause), individuals consider the expectations of groups with which they identify. These expectations are injunctive norms, shared beliefs about appropriate behavior for identity group members, and individuals' choices reflect trade‐offs between adherence to these norms...

We examine the roots of variation in corruption across societies, and we argue that marriage practices and family structure are an important, overlooked determinant of corruption. By shaping patterns of relatedness and interaction, marriage practices influence the relative returns to norms of nepotism/favoritism versus norms of impartial cooperatio...

The ability of markets to aggregate diverse information is a cornerstone of economics and finance, and empirical evidence for such aggregation has been demonstrated in previous laboratory experiments. Most notably Plott and Sunder (1988) find clear support for the rational expectations hypothesis in their Series B and C markets. However, recent stu...

The special issue aims to bring together different perspectives on conflict and war from different disciplines, including economics, psychology, evolutionary biology, anthropology, political science, and management. By collecting these distinct, but overlapping perspectives in a single issue, we hope to encourage interdisciplinary work on conflict...

Experimental studies of favoritism and corruption typically examine such behavior among strangers, but ethnic and kinship ties have long been viewed as potential catalysts for favoritism, and hence corruption. In this paper, we provide evidence from lab experiments on the effect of kinship and ethnic ties on favoritism. We report behavior in a game...

A survey of instruction delivery and reinforcement methods in recent laboratory experiments reveals a wide and inconsistently reported variety of practices and limited research evaluating their effectiveness. Thus, we experimentally compare how methods of delivering and reinforcing experiment instructions impact subjects’ comprehension and retentio...

What determines the geographic extent of territory? We microfound and extend Boulding’s “Loss of Strength Gradient” to predict the extensive and intensive margins of conflict across space. We show how economies of scale in the production of violence and varying costs of projecting violence at a distance combine to affect the geographic distribution...

We investigate in an economic experiment how people choose sides in disputes. In an eight-player side-taking game, two disputants at a time fight over an indivisible resource and other group members choose sides. The player with more supporters wins the resource, which is worth real money. Conflicts occur spontaneously between any two individuals i...

Recent models of prosociality suggest that cooperation in laboratory games may be better understood as resulting from concern for social norms than from prosocial preferences over outcomes. Underlying this interpretation is the idea that people exhibit heterogeneous respect for shared norms. We introduce a new, abstract task to elicit a proxy for i...

We report boundary experiments testing the robustness of price convergence in double auction markets for non-durable goods in which there is extreme earnings inequality at the competitive equilibrium (CE). Following up on a conjecture by Smith (1976a), we test whether the well-known equilibrating power of the double auction institution is robust to...

While economists recognize the important role of formal institutions in the promotion of trade, there is increasing agreement that institutions are typically endogenous to culture, making it difficult to disentangle their separate contributions. Lab experiments that assign institutions exogenously and measure and control individual cultural charact...

We investigate our capacity to attribute preferences to others. This ability is intrinsic to game theory, and is a central component of “Theory of Mind”, perhaps the capstone of social cognition. This component of theory of mind allows individuals to learn more rapidly in strategic environments with an element of novelty. We show that the capacity...

We report an experimental test of alternative rules in innovation contests when success may not be feasible and contestants may learn from each other. Following Halac, Kartik, and Liu (in press), the contest designer can vary the prize allocation rule from Winner-Take-All (WTA) in which the first successful innovator receives the entire prize to Sh...

We review the main economic models of war and conflict. These models vary in details, but their implications are qualitatively consistent, highlighting key commonalities across a variety of conflict settings. Recent empirical literature, employing both laboratory and field data, in many cases confirms the basic implications of conflict theory. Howe...

In laboratory asset markets, subjects trade shares of a firm whose profits in a linked product market determine dividends. Treatments vary whether dividend information is revealed once per period or in real time and whether the firm is controlled by a profit-maximizing robot or human subject. The latter variation induces uncertainty about firm beha...

Norms of nepotism and favoritism create corruption, subverting and disrupting impartial institutions and hampering economic development. However, the presence and strength of such norms varies widely within and between countries, and the literature has suggested that this variation is driven, in part, by ethnic fractionalization, with mixed results...

Voters are often observed voting “against their interests”. We argue this is because voters don’t just ask themselves “which party best represents my policy preferences?” but also ask “how is someone like me supposed to vote?” Voters don’t just consider their personal preferences. They also consider the expectations of the salient groups with which...

This paper investigates our capacity to attribute preferences to others. This ability is intrinsic to game theory, and is a central component of "Theory of Mind'', perhaps the capstone of social cognition. In particular, this component of theory of mind allows individuals to learn more rapidly in strategic environments with an element of novelty. W...

We report an experimental test of alternative rules in innovation contests when success may not be feasible and contestants may learn from each other. Following Halac, Kartik, and Liu (in press), the contest designer can vary the prize allocation rule from Winner‐Take‐All (WTA) in which the first successful innovator receives the entire prize to Sh...

Objectives With increasing attention being paid to inequality and poverty, this article attempts to shed light on mechanisms by which the poor arrive at decisions that are suboptimal and lead to “poverty traps.” Methods We design a laboratory experiment in which we induce wealth and income differences between subjects to compare their behavior in...

When individuals trade with strangers, there is a temptation to renege on agreements. If repeated interaction or exogenous enforcement is unavailable, societies often solve this problem via institutions that rely on group, rather than individual, reputation. Groups can employ two mechanisms to uphold reputation that are unavailable to individuals:...

Tournaments consisting of iterative matches are a common mechanism for determining how to allocate a prize. While participants are focused on their own outcomes, tournament organizers often have objectives such as maxi-mizing the total investment or effort by the participants over the course of the tournament. For this reason it is important for or...

Commitment problems are inherent to non-binding conflict resolution mechanisms, since an unsatisfied party can ignore the resolution and initiate conflict. We provide experimental evidence suggesting that even in the absence of binding contractual agreements individuals often avoid conflict by committing to the outcome of a conflict resolution mech...

We design an experiment to explore the impact of earned entitlements on the frequency and intensity of conflicts in a two-stage conflict game with side-payments. In this game, residents (Proposers) make side-payment offers and contestants (Responders) decide whether to accept the offers and whether to engage in a conflict. When subjects earn their...

We model competition between two firms selling identical goods to customers who arrive in the market stochastically. Shoppers choose where to purchase based upon both price and the time cost associated with waiting for service. One seller provides two separate queues, each with its own server, while the other seller has a single queue and server. W...

Due to the high costs of conflict both in theory and practice, we examine and experimentally test the conditions under which conflict between asymmetric agents can be resolved. We model conflict as a two-agent rent-seeking contest for an indivisible prize. Before conflict arises, both agents may agree to allocate the prize by fair coin flip to avoi...

In laboratory asset markets, subjects trade shares of a firm whose profits in a linked product market determine dividends. Treatments vary whether dividend information is revealed once per period or in real-time and whether the firm is controlled by a profit-maximizing robot or human subject. The latter variation induces uncertainty about firm beha...

Due to the high costs of conflict both in theory and practice, we examine and experimentally test the conditions under which conflict between asymmetric agents can be resolved. We model conflict as a two-agent rent-seeking contest for an indivisible prize. Before conflict arises, both agents may agree to allocate the prize by fair coin flip to avoi...

Donations and volunteerism can be conceived as market transactions with zero explicit price. However, evidence suggests people may not view zero as just another price when it comes to pro-social behavior. Thus, while markets might be expected to increase the supply of assets available to those in need, some worry such financial incentives will crow...

The history of the world is strewn with the remains of societies whose institutions failed to adapt to ecological change, but the determinants of institutional fragility are difficult to identify in the historical record. We report a laboratory experiment exploring the impact of an exogenous ecological shock on the informal rules of property and ex...

Commitment problems are inherent to non-binding conflict resolution mechanisms, since an unsatisfied party can ignore the resolution and initiate conflict. We provide experimental evidence suggesting that even in the absence of binding contractual agreements individuals often avoid conflict by committing to the outcome of a conflict resolution mech...

We study a novel, repeated common pool resource game in which current resource stocks depend on resource extraction in previous periods. Our model shows that for a sufficiently high regrowth rate, there is no commons dilemma: the resource will be preserved indefinitely in equilibrium. Lower growth rates lead to depletion. Laboratory tests of the mo...

This paper investigates the evolutionary foundation for our capacity to attribute preferences to others. This ability is intrinsic to game theory, and is a key component of "Theory of Mind'' (ToM), perhaps the capstone of social cognition. We argue here that this component of theory of mind allows organisms to efficiently modify their behavior in s...

When individuals trade with strangers, there is a temptation to renege on con- tracts. In the absence of repeated interaction or exogenous enforcement mechanisms, this problem can impede valuable exchange. Historically, individuals have solved this problem by forming institutions that sustain trade using group, rather than individ- ual, reputation....