Other Economics Commons^™

Variation Among Populations In The Immune Protein Composition Of Mother's Milk Reflects Subsistence Pattern, Laura D. Klein, Jincui Huang, Elizabeth A. Quinn, Melanie A. Martin, Alicia A. Breakey, Michael Gurven, Hillard Kaplan, Claudia Valeggia, Grazyna Jasienska, Brooke Scelza, Carlito B. Lebrilla, Katie Hinde

ESI Publications

Lay Summary: Adaptive immune proteins in mothers’ milk are more variable than innate immune proteins across populations and subsistence strategies. These results suggest that the immune defenses in milk are shaped by a mother’s environment throughout her life.

Background and objectives: Mother’s milk contains immune proteins that play critical roles in protecting the infant from infection and priming the infant’s developing immune system during early life. The composition of these molecules in milk, particularly the acquired immune proteins, is thought to reflect a mother’s immunological exposures throughout her life. In this study, we examine the composition of innate …

Do Negative Random Shocks Affect Trust And Trustworthiness?, Hernán Bejarano, Joris Gillet, Ismael Rodriguez-Lara

ESI Publications

We report data from a variation of the trust game aimed at determining whether (and how) inequality and random shocks that affect wealth influence the levels of trust and trustworthiness. To tease apart the effect of the shock and the inequality, we compare behavior in a trust game where the inequality is initially given and one where it is the result of a random shock that reduces the second mover's endowment. We find that first‐movers send less to second‐movers but only when the inequality results from a random shock. As for the amount returned, second‐movers return less when they are …

Do Negative Random Shocks Affect Trust And Trustworthiness?, Hernán Bejarano, Joris Gillet, Ismael Rodriguez-Lara

ESI Publications

We report data from a variation of the trust game aimed at determining whether (and how) inequality and random shocks that affect wealth influence the levels of trust and trustworthiness. To tease apart the effect of the shock and the inequality, we compare behavior in a trust game where the inequality is initially given and one where it is the result of a random shock that reduces the second mover's endowment. We find that first‐movers send less to second‐movers but only when the inequality results from a random shock. As for the amount returned, second‐movers return less when they are …

Marital Violence And Fertility In A Relatively Egalitarian High-Fertility Population, Jonathan Stieglitz, Benjamin C. Trumble, Hillard Kaplan, Michael Gurven

ESI Publications

Ultimate and proximate explanations of men’s physical intimate partner violence (IPV) against women have been proposed. An ultimate explanation posits that IPV is used to achieve a selfish fitness-relevant outcome, and predicts that IPV is associated with greater marital fertility. Proximate IPV explanations contain either complementary strategic components (for example, men’s desire for partner control), non-strategic components (for example, men’s self-regulatory failure), or both strategic and non-strategic components involving social learning. Consistent with an expectation from an ultimate IPV explanation, we find that IPV predicts greater marital fertility among Tsimané forager-horticulturalists of Bolivia (n = 133 marriages, 105 women). This …

Correction To: 'Greater Wealth Inequality, Less Polygyny: Rethinking The Polygyny Threshold Model', Cody T. Ross, Monique Borgerhoff Mulder, Seung-Yun Oh, Samuel Bowles, Bret Beheim, John Bunce, Mark Caudell, Gregory Clark, Heidi Colleran, Carmen Cortez, Patricia Draper, Russell D. Greaves, Michael Gurven, Thomas Headland, Janet Headland, Kim Hill, Barry Hewlett, Hillard Kaplan, Jeremy Koster, Karen Kramer, Frank Marlowe, Richard Mcelereath, David Nolin, Marsha Quinlan, Robert Quinlan, Caissa Revilla-Minaya, Brooke Scelza, Ryan Schacht, Mary Shenk, Ray Uehara, Eckart Voland, Kai Willführ, Bruce Winterhalder, John Ziker, Christopher Von Rueden

ESI Publications

No abstract provided.

Greater Wealth Inequality, Less Polygyny: Rethinking The Polygyny Threshold Model, Cody T. Ross, Monique Borgerhoff Mulder, Seung-Yun Oh, Samuel Bowles, Bret Beheim, John Bunce, Mark Caudell, Gregory Clark, Heidi Colleran, Carmen Cortez, Patricia Draper, Russell D. Greaves, Michael Gurven, Thomas Headland, Janet Headland, Kim Hill, Barry Hewlett, Hillard Kaplan, Jeremy Koster, Karen Kramer, Frank Marlowe, Richard Mcelreath, David Nolin, Marsha Quinlan, Robert Quinlan, Caissa Revilla-Minaya, Brooke Scelza, Ryan Schacht, Mary Shenk, Ray Uehara, Eckart Voland, Kai Willführ, Bruce Winterhalder, John Ziker, Christopher Von Rueden

ESI Publications

Monogamy appears to have become the predominant human mating system with the emergence of highly unequal agricultural populations that replaced relatively egalitarian horticultural populations, challenging the conventional idea—based on the polygyny threshold model—that polygyny should be positively associated with wealth inequality. To address this polygyny paradox, we generalize the standard polygyny threshold model to a mutual mate choice model predicting the fraction of women married polygynously. We then demonstrate two conditions that are jointly sufficient to make monogamy the predominant marriage form, even in highly unequal societies. We assess if these conditions are satisfied using individual-level data from 29 human …

Sleep Variability And Nighttime Activity Among Tsimane Forager‐Horticulturalists, Gandhi Yetish, Hillard Kaplan, Michael Gurven

ESI Publications

Objectives

A common presumption in sleep research is that “normal” human sleep should show high night‐to‐night consistency. Yet, intra‐individual sleep variation in small‐scale subsistence societies has never been studied to test this idea. In this study, we assessed the degree of nightly variation in sleep patterns among Tsimane forager‐horticulturalists in Bolivia, and explored possible drivers of the intra‐individual variability.

Methods

We actigraphically recorded sleep among 120 Tsimane adults (67 female), aged 18–91, for an average of 4.9 nights per person using the Actigraph GT3X and Philips Respironics Actiwatch 2. We assessed intra‐individual variation using intra‐class correlations and average deviation from …

Land Assembly With Taxes, Not Takings, Mark Desantis, Matthew W. Mccarter, Abel Winn

ESI Publications

We use a novel tax mechanism – ‘rejected offer reassessment’ (ROR) – in laboratory experiments to discourage seller holdout and facilitate land assembly. Under this mechanism, if a landowner rejects a developer’s offer, his taxable property value is reassessed to be equal to the rejected offer, increasing his taxes. We find that, relative to a control treatment, ROR discourages the magnitude of seller holdout (but not its frequency) and increases the rate of successful land assembly by almost 60%. It also increases the gains from trade by 22.1% relative to the control treatment, but the difference is not statistically significant.

Goal Setting In The Principal-Agent Model: Weak Incentives For Strong Performance, Brice Corgnet, Joaquín Gómez-Miñambres, Roberto Hernán-González

ESI Publications

We study a principal–agent framework in which principals can assign wage-irrelevant goals to agents. We find evidence that, when given the possibility to set wage-irrelevant goals, principals select incentive contracts for which pay is less responsive to agents' performance. Agents' performance is higher in the presence of goal setting despite weaker incentives. We develop a principal–agent model with reference-dependent utility that illustrates how labor contracts combining weak monetary incentives and wage-irrelevant goals can be optimal. The pervasive use of non-monetary incentives in the workplace may help account for previous empirical findings suggesting that firms rely on unexpectedly weak monetary incentives.

A Theory Of Focal Points In 2x2 Games, Jonathan W. Leland, Mark Schneider

ESI Publications

Since the classic work of Schelling, the notion of a focal point has been widely applied to explain coordinated behavior. However, focal points remain largely outside the formal apparatus of game theory. This paper develops a model of play in 2 × 2 games where payoff differences determine what strategy players will perceive as “salient” and choose to play. The model uniquely predicts which outcome will emerge for virtually the entire class of 2 × 2 normal form games. For the subset of such games involving coordination and asymmetric payoffs, payoff differences identify focal outcomes and strategies in the same …

Sex Differences In Political Leadership In An Egalitarian Society, Christopher Von Rueden, Sarah Alami, Hillard Kaplan, Michael Gurven

ESI Publications

We test the contribution of sex differences in physical formidability, education, and cooperation to the acquisition of political leadership in a small-scale society. Among forager-farmers from the Bolivian Amazon, we find that men are more likely to exercise different forms of political leadership, including verbal influence during community meetings, coordination of community projects, and dispute resolution. We show that these differences in leadership are not due to gender per se but are associated with men’s greater number of cooperation partners, greater access to schooling, and greater body size and physical strength. Men’s advantage in cooperation partner number is tied to …

Low Perceived Control Over Health Is Associated With Lower Treatment Uptake In A High Mortality Population Of Bolivian Forager-Farmers, Sarah Alami, Jonathan Stieglitz, Hillard Kaplan, Michael Gurven

ESI Publications

Indigenous people worldwide suffer from higher rates of morbidity and mortality than neighboring populations. In addition to having limited access to public health infrastructure, indigenous people may also have priorities and health perceptions that deter them from seeking adequate modern healthcare. Here we propose that living in a harsh and unpredictable environment reduces motivation to pursue deliberate, costly action to improve health outcomes. We assess whether variation in Health Locus of Control (HLC), a psychological construct designed to capture self-efficacy with respect to health, explains variation in treatment uptake behavior among Tsimane Amerindians (N=690; age range: 40–89 years; 55.8% female; …

Information Transmission And The Oral Tradition: Evidence Of A Late-Life Service Niche For Tsimane Amerindians, Eric Schniter, Nathaniel T. Wilcox, Bret A. Beheim, Hillard S. Kaplan, Michael Gurven

ESI Publications

Storytelling can affect wellbeing and fitness by transmitting information and reinforcing cultural codes of conduct. Despite their potential importance, the development and timing of storytelling skills, and the transmission of story knowledge have received minimal attention in studies of subsistence societies that more often focus on food production skills. Here we examine how storytelling and patterns of information transmission among Tsimane forager-horticulturalists are predicted by the changing age profiles of storytellers’ abilities and accumulated experience. We find that storytelling skills are most developed among older adults who demonstrate superior knowledge of traditional stories and who report telling stories most. We …

Who’S Holding Out? An Experimental Study Of The Benefits And Burdens Of Eminent Domain, Abel Winn, Matthew W. Mccarter

ESI Publications

A substantial literature identifies seller holdout as a serious obstacle to land assembly, implying that eminent domain is an appropriate policy response. We conduct a series of laboratory experiments to test this view. We find that when there is no competition and no eminent domain, land assembly suffers from costly delay and failed assembly: participants lose 18.8% of the available surplus on average. Much of the inefficiency is due to low offers from the buyers (“buyer holdout”) rather than strategic holdout among sellers. When buyers can exercise eminent domain the participants lose 19.4% of the surplus on average. This loss …

The Welfare Effects Of Civil Forfeiture, Michael Preciado, Bart J. Wilson

ESI Publications

Using a laboratory experiment we explore competing claims on the welfare effects of civil forfeiture. Experiment participants are tasked with making trade-offs in allocating resources “to fight crime” with and without the ability to seize and forfeit assets. It is an open question whether the societal impact of reducing crime is greater in a world with or without civil forfeiture. Proponents of civil forfeiture argue that the ill-gotten gains of criminals can be used by law enforcement to further fight crime. Opponents claim that the confiscation of assets by law enforcement distorts the prioritization of cases by focusing attention, not …

Human And Monkey Responses In A Symmetric Game Of Conflict With Asymmetric Equilibria, Sarah F. Brosnan, Sara A. Price, Kelly Leverett, Laurent Prétôt, Michael Beran, Bart J. Wilson

ESI Publications

To better understand the evolutionary history of human decision-making, we compare human behavior to that of two monkey species in a symmetric game of conflict with two asymmetric equilibria. While all of these species routinely make decisions in the context of social cooperation and competition, they have different socio-ecologies, which leads to different predictions about how they will respond. Our prediction was that anti-matching would be more difficult than matching in a symmetric coordination with simultaneous moves. To our surprise, not only do rhesus macaques frequently play one asymmetric Nash equilibrium, but so do capuchin monkeys, whose play in the …

Historical Cost And Conservatism Are Joint Adaptations That Help Identify Opportunity Cost, Sudipta Basu, Gregory B. Waymire

ESI Publications

Braun (The ecological rationality of historical costs and conservatism. Accounting, Economics and Law: A Convivium, this issue) argues that the traditional accounting principles underlying the revenue-expense approach such as Historical Cost and Conservatism are ecologically rational in that they help organizations survive better in uncertain economic environments. More importantly, Braun argues that the revenue-expense approach generates new private information, which informs markets and makes them more effective (Hayek, 1945, The use of knowledge in society. The American Economic Review, 35(4), 519–530), as opposed to merely reflecting back market data under the asset-liability approach (e.g. Sunder, 2011, IFRS monopoly: …

Experimenting With Contests For Experimentation, Cary Deck, Erik O. Kimbrough

ESI Publications

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 Shared in which all successful innovators during the contest duration share in the prize. The designer can also vary the information disclosure policy from Public in which at each period, all information about contestants' past successes and failures is publicly available, to Private, in which contestants …

Informed Entry In Auctions, Diego Aycinena, Hernán Bejarano, Lucas Rentschler

ESI Publications

We examine entry decisions in first-price and English clock auctions with participation costs. Potential bidders observe their value and report maximum willingness to pay (WTP) to participate. Entry occurs if revealed WTP (weakly) exceeds the randomly drawn participation cost. We find no difference in WTP between auction formats, although males have a higher WTP for first-price auctions. WTP is decreasing in the number of potential bidders, but this reduction is less than predicted and small in magnitude.

Sentiments, Conduct, And Trust In The Laboratory, Vernon Smith, Bart J. Wilson

ESI Publications

In this essay we provide a brief account and interpretation of The Theory of Moral Sentiments showing that it departs fundamentally from contemporary patterns of thought in economics that are believed to govern individual behavior in small groups, and contains strong testable propositions governing the expression of that behavior. We also state a formal representation of the model for individual choice of action, apply the propositions to the prediction of actions in trust games, report two experiments testing these predictions, and interpret the results in terms directly related to the model. In short, we argue that the system of sociability …

Sleep Restriction And Circadian Effects On Social Decisions, David L. Dickinson, Todd Mcelroy

ESI Publications

Our study examines how chronic sleep restriction and suboptimal times-of-day affect decisions in a classic set of social tasks. We experimentally manipulate and objectively measured sleep in 184 young-adult subjects, who were also randomly assigned an early morning or late evening experiment session during which decision tasks were administered. Sleep restriction and suboptimal time-of-day are both estimated to either directly or indirectly (via an impact on sleepiness) reduce altruism, trust, and trustworthiness. We conclude that commonly experienced adverse sleep states, most notably chronic sleep restriction, significantly reduce prosocial behaviors, and can therefore limit benefits from short-term social interactions.

Emotions And Behavior Regulation In Decision Dilemmas, Joaquín Gómez-Miñambres, Eric Schniter

ESI Publications

We introduce a dynamic model of emotional behavior regulation that can generalize to a wide range of decision dilemmas. Dilemmas are characterized by availability of mutually exclusive goals that a decision maker is dually motivated to pursue. In our model, previous goal pursuant decisions produce negative emotions that regulate an individual’s propensity to further pursue those goals at future times. This emotional regulation of behavior helps explain the non-stationarity and switching observed between so-called “preferences” revealed in repeated decision dilemmas (e.g., by choosing A over B at time 1, then choosing B over A at time 2). We also explain …

On Private Governance, Bart J. Wilson

ESI Publications

Edward Peter Stringham’s book Private Governance: Creating Order in Economic and Social Life (2015) is a compelling defense of the proposition that private governance is more widely used and more effective than most people think. Stringham looks to history to see how people solved problems of fraud and cheating without government intervention and provides example after compelling example to contradict the strong claim that a government or any third-party enforcer is necessary for voluntary exchange. While Stringham doesn’t take on the tough problem that private governance is not sufficient for its task, his book is intended to be the beginning, …

How We Think About Economics, Bart J. Wilson

ESI Publications

"From my casual observation, many economists were surprised at the content of Vernon's Nobel lecture on ecological and constructivist rationality in economics. Having been awarded the prize 'for having established laboratory experiments as a tool in empirical economic analysis, especially in the study of alternative market mechanisms,' I think many expected him to catalogue the major findings of experimental economics in his prize lecture. David Porter has described Vernon as a live, interactive version of the Journal of Economic Literature. But Vernon Smith is no cataloguer. He is a synthesizer, and he synthesizes acutely aware that scientific inquiry is …

Comparing A Risky Choice In The Field And Across Lab Procedures, Zuzana Brokesova, Cary Deck, Jana Peliova

ESI Publications

Controlled laboratory experiments have become a generally accepted method for studying economic behavior, but there are two issues regarding the reliability of such work. The first pertains to the ability to generalize experimental results outside the laboratory. The second pertains to the impact the payment procedure has on observed behavior. This paper adds empirical insight into both issues. Using data from the promotional campaign of a bank and a laboratory experiment that closely mimics the same decision, we find similar levels of risk taking controlling for gender and age. We also compare behavior on this same risky choice across three …

Coronary Atherosclerosis In Indigenous South American Tsimane: A Cross-Sectional Cohort Study, Hillard Kaplan, Randall C. Thompson, Benjamin C. Trumble, L. Samuel Wann, Adel H. Allam, Bret Beheim, Bruno Frohlich, M. Linda Sutherland, James D. Sutherland, Jonathan Stieglitz, Daniel Eid Rodriguez, David E. Michalik, Chris J. Rowan, Guido P. Lombardi, Ram Bedi, Angela R. Garcia, James K. Min, Jagat Narula, Caleb E. Finch, Michael Gurven, Gregory S. Thomas

ESI Publications

Background—Conventional coronary artery disease risk factors might potentially explain at least 90% of the attributable risk of coronary artery disease. To better understand the association between the pre-industrial lifestyle and low prevalence of coronary artery disease risk factors, we examined the Tsimane, a Bolivian population living a subsistence lifestyle of hunting, gathering, fishing, and farming with few cardiovascular risk factors, but high infectious inflammatory burden.

Methods—We did a cross-sectional cohort study including all individuals who self-identified as Tsimane and who were aged 40 years or older. Coronary atherosclerosis was assessed by coronary artery calcium (CAC) scoring done with …

Smile, Dictator, You’Re On Camera, Joy A. Buchanan, Matthew K. Mcmahon, Matthew Simpson, Bart J. Wilson

ESI Publications

We investigate the degree to which people in a shopping mall express other-regarding behavior in the dictator game. Whereas many studies have attempted to increase the social distance between the dictator and experimenter and between the dictator and dictatee, we attempt to minimize that social distance between random strangers by video recording the decisions with the permission of the dictators to display their image on the Internet. Offers made by dictators are high relative to other experiments and a nontrivial number give the entire experimental windfall away, however a nontrivial number of people keep everything as well.

The Tsimane Health And Life History Project: Integrating Anthropology And Biomedicine, Michael Gurven, Jonathan Stieglitz, Benjamin C. Trumble, Aaron D. Blackwell, Bret Beheim, Helen Davis, Hillard Kaplan, Paul L. Hooper

ESI Publications

The Tsimane Health and Life History Project, an integrated bio-behavioral study of the human life course, is designed to test competing hypotheses of human life-history evolution. One aim is to understand the bidirectional connections between life history and social behavior in a highfertility, kin-based context lacking amenities of modern urban life (e.g. sanitation, banks, electricity). Another aim is to understand how a high pathogen burden influences health and well-being during development and adulthood. A third aim addresses how modernization shapes human life histories and sociality. Here we outline the project’s goals, history, and main findings since its inception in 2002. …

A Study Of The Triggers Of Conflict And Emotional Reactions, Michael Caldera, Michael T. Mcbride, Matthew W. Mccarter, Roman M. Sheremeta

ESI Publications

We study three triggers of conflict and explore their resultant emotional reactions in a laboratory experiment. Economists suggest that the primary trigger of conflict is monetary incentives. Social psychologists suggest that conflicts are often triggered by fear. Finally, evolutionary biologists suggest that a third trigger is uncertainty about an opponent’s desire to cause harm. Consistent with the predictions from economics, social psychology, and evolutionary biology, we find that conflict originates from all three triggers. The three triggers differently impact the frequency of conflict, but not the intensity. Also, we find that the frequency and intensity of conflict decrease positive emotions …

Emotional Calibration Of Self-Control, Joaquín Gómez-Miñambres, Eric Schniter

ESI Publications

We study a dynamic model of self-control where previous decisions have influence on subsequent decision making. In our model effort and guilt are negative emotions produced by previous decisions to either resist or yield to temptation, respectively. These emotions calibrate an individual's self-control, in turn affecting future decisions. Our model explains non-stationary consumption paths characterized by compensatory indulgence and restraint, why under some circumstances the amplitude of this switching pattern increases with foresight, and how unavoidable options that might show up on one's menu influence choices, consequent emotions, consumption paths, and preferences for commitment. We discuss the implications of self-control …