We contribute to a large literature that explores prosocial behavior in public goods experiments. We adopt an experimental design that allows full contribution to the public good to be sustained in equilibrium. We study the effect of the time horizon on a subject's propensity to contribute to a public good by varying the stopping rule for the game. While many studies examine the effect of a random stopping rule in prisoner's dilemma games, to our knowledge, only two other studies have directly compared behavior in public goods experiments with finite and random stopping rules. Consistent with existing studies, we find that contribution rates are similar across treatments in early rounds of play, and contribution rates are higher with random verses finite stopping rules in later rounds. Overall, we find significantly higher contributions to the public good when donors face a known probability of future interactions with the same group of participants compared to interactions with a finite endpoint. Further, the difference in cooperative behavior is driven primarily by the stopping rule, rather than the length of the game.

I experimentally investigate the relation of endowment origin, cognitive abilities (as measured by the Cognitive Reflection Test, CRT), and co-operation in a one-shot linear public goods game. The results show that subjects’ contributions depend on an interplay of cognitive abilities and endowment origin. A house money effect exists only for subjects with low CRT scores. They contribute more when income was allocated to them and less when income was obtained by effort. In contrast, subjects with high CRT scores contribute the same amount independent of income type. The findings have implications for redistribution, team production, and experimental designs.

Offline volunteering was faced with new challenges during the COVID-19 pandemic. Using a survey experiment with 1207 student participants, we test the impact of informing subjects about blood donation urgency (shortage information), and secondly, the effect of providing information about measures taken to reduce SARS-CoV-2 transmission at blood donation centers (hygiene information), on their inclination to donate during and after the COVID-19 lockdown. The results show that shortage information increases extensive-margin willingness to donate for non-donors by 15 percentage points (pp), on average, and increases the willingness to donate quickly for all respondents. Hygiene information, however, reduces prior donors’ intention to donate again by 8pp, on average, and reduces the willingness of non-donors to donate quickly.

We experimentally study how mutual payoff information affects strategic play. Subjects play the Prisoner's Dilemma or Stag Hunt game against randomly re-matched opponents under two information treatments. In our partial-information treatment, subjects are shown only their own payoff structure, while in our full-information treatment they are shown both their own and their opponent's payoff structure. In both treatments, they receive feedback on their opponent's action after each round. We find that mutual payoff information initially facilitates reaching the socially optimal outcome in both games. Play in the Prisoner's Dilemma converges toward the unique Nash equilibrium of the game under both information treatments, while in the Stag Hunt mutual payoff information has a substantial impact on play and equilibrium selection in all rounds of the game. Belief-learning model estimations and simulations suggest these effects are driven by both initial play and the way subjects learn.

This paper investigates risk preferences using an artefactual field experiment conducted with a non-standard subject pool of farmers in Ghana. I introduce an alternative methodology for studying preferences following replication of a seminal risk elicitation procedure by Binswanger (Am J Agric Econ 62(3):395407, 1980). An important feature of both approaches is that they are easy to understand and, hence, are particularly suitable for eliciting preferences among subjects with low levels of formal education. I successfully replicate Binswanger's study, documenting how his original result of the moderate level of risk aversion for an average farmer can be generalized to a different country. However, using my alternative approach, whereby lotteries are presented in the loss domain, I find that half of my experimental subjects violated expected utility theory. This approach is of relevance to the current literature on studying risk preferences among subjects with poor literacy skills.

The widespread Internet “piracy” continues to fuel the debate about business models impervious to copyright infringement. We studied the displacement effects of “piracy” on sales in the book industry. We conducted a year-long large-scale field experiment: in the treatment group, we removed unauthorised copies appearing on the Internet and observed the sales data, whereas in the control group, we simply observed sales. We were able to substantially curb the unauthorised distribution, which resulted in a small, positive effect on sales. While using classical analysis we found it not to be significantly different from zero, a Bayesian approach using previous “piracy” studies to generate a prior led to the conclusion that protecting from piracy resulted in a significant sales boost of about 9 per cent.

Empirical evidence has shown that people with better self-control to a greater extent have the self-regulatory ability to act in line with their long-term goals. In this pre-registered study, the relationship between self-control and self-regulatory behavior was investigated both directly and indirectly, i.e., through affective forecasting ability. This is of great interest as it is necessary to be able to forecast one's emotional response to future events in order to make choices that maximize one's happiness. However, in a laboratory experiment with undergraduate students, I found no evidence of self-control being associated with affective forecasting ability, or that people with better self-control more often acted in a way that maximized their expected happiness.

Are economic decisions affected by short-term stress, failure, or both? Such effects have not been clearly distinguished in previous experimental research, and have the potential to worsen economic outcomes, especially in disadvantaged socioeconomic groups. We validate a novel experimental protocol to examine the individual and combined influences of stress, failure, and success. The protocol employs a 2 × 3 experimental design in two sessions and can be used online or in laboratory studies to analyse the impact of these factors on decision-making and behaviour. The stress protocol was perceived as significantly more stressful than a control task, and it induced a sizeable and significant rise in state anxiety. The provision of negative feedback (“failure”) significantly lowered participants’ assessment of their performance, induced feelings of failure, and raised state anxiety.

This paper examines the impact of different ways of inducing discounting in alternating-offer bargaining games in the lab. We examine this by following the framework of Ochs and Roth (Am Econ Rev, pp. 355–384, 1989) and test whether the model's predictions find support in data under three different discounting implementations; the shrinking-pie procedure, the effective-discounting procedure and the bargaining-delay procedure. We find no sensitivity to the number of periods in any of the three procedures. However, we find mixed evidence for the effect of changing the discount factor in the effective-discounting procedure and the shrinking-pie procedure, but the magnitude of effects are small. Furthermore, there was more disagreement in both the effective-discounting and bargaining-delay procedures than in the shrinking-pie procedure.

Decision makers typically possess limited knowledge on states of the world so that use of information from past similar experiences is reasonable. This analogical thinking is formalised by case-based decision theory (CBDT). We created a novel experimental setting to validate the predictive power of CBDT versus Bayesian reasoning. Participants encountered a salient but irrelevant cue which a Bayesian decision maker is likely to ignore but a case-based decision maker may use in assessing similarity. We find that although the irrelevant similarity cue was used, the pattern in participants’ decisions is neither case-based nor Bayesian. The results suggest that CBDT does not apply in simple decision settings where similarity cues are uninformative.

We study the robustness of Krupka and Weber's method (2013) for eliciting social norms. In two online experiments with more than 1200 participants on Amazon Mechanical Turk, we find that participants’ response patterns are invariant to differences in the salience of the monetarily incentivized coordination aspect. We further demonstrate that asking participants for their personal first- and second-order beliefs without monetary incentives results in qualitatively identical responses in the case that beliefs and social norms are well aligned. Overall, Krupka and Weber's method produces remarkably robust response patterns.

The Inclusion of Other in the Self (IOS) scale is a popular tool to measure interpersonal closeness that is increasingly being used in economics. We develop and validate a continuous version of the IOS scale. This Continuous IOS scale gives a finer measure and addresses the reluctance of subjects to report low scores on the standard IOS scale. We also propose a version of the standard IOS scale that meets its original design features. Our IOS scales are easy-to-use, well-documented, standardised, and available at https://github.com/geoffreycastillo/ios-js.

We ask whether social preferences measured in subjects who come to the laboratory when invited are systematically different from those of subjects who only respond when an online option is available. Subjects participated in two types of third-party (other–other) dictator games and a trust game, either in the lab or on-line. In the third party dictator games, the dictator divides $20 between two other individuals, one of whom is a member of their in-group. (We also varied types of in-group between a real group and an artificial group.) In the trust game, the first-mover decides how much of the endowment to send to the second-mover. The second-mover receives the amount sent tripled by the experimenter and decides how much to send back to the trustee. Across all the games, we find no statistically significant differences in social preferences measured in-lab and on-line.

We explore gender differences in individuals’ motivations. We focus on guilt aversion and moral commitment. Our experiment supports the idea that men are more guilt-averse than women, while moral motivations drive more women's actions in a random dictator game with pre-play communication.

We introduce a novel way to elicit individuals’ strength of altruistic motivation in the context of charitable donations, ranging from pure warm glow to pure altruism. Using the giving-type elicitation task of Gangadharan et al. (2018) and assuming that individuals maximise a Cobb–Douglas impure altruism utility function, as is used in Ottoni-Wilhelm et al. (2017), we can uniquely identify the strength of altruistic motivation for impure altruists, which is typically found to be the largest category of donors. We compare the introduced measure to an alternative survey-based elicitation from Carpenter (2021).

While people are surprisingly cooperative in social dilemmas, cooperation is fragile to the emergence of defection. Punishment is a key mechanism through which people sustain cooperation, but when are people willing to pay the costs to punish? Using data from existing work on punishment in public goods games conducted in industrialized countries throughout the world (Herrmann et al. in Science, 319(5868):1362–1367, 2008. https://doi.org/10.1126/science.1144237), I find first that those who contribute more are consistently punished less. Second, in many study locations, there are insignificant differences in the propensity of those who contribute and defect to punish. Finally, those who contribute and defect both carry out punishment against defectors. Some defectors do punish cooperators, but less often than they punish other defectors. The determinants of punishment are largely consistent across cities.

MTVE is an open-source software tool (citeware) that can be applied in laboratory and online experiments to implement video communication. The tool enables researchers to gather video data from these experiments in a way that these videos can be later used for automatic analysis through machine learning techniques. The browser-based tool comes with an easy user interface and can be easily integrated into z-Tree, oTree (and other experimental or survey tools). It provides the experimenters control over several communication parameters (e.g., number of participants, resolution), produces high-quality video data, and circumvents the Cocktail Party Problem (i.e., the problem of separating speakers solely based on audio input) by producing separate files. Using some of the recommended Voice-to-Text AI, the experimenters can transcribe individual files. MTVE can merge these individual transcriptions into one conversation.