We conduct an experiment on an online game, exploring the effect on gameplay behavior of voluntary commitment devices that allow players to limit their gameplay. Approximately 25% of players use the devices. Median and 75th percentile device users use devices approximately 60 and 100% of the time, respectively. Players who chose to use the device were those who had previously played longer and more frequently than those who chose not to use the device. Offering the commitment devices decreased session length and session frequency by 2.8 and 6.1%, respectively, while increasing weeks of play by 5.5%. Our results are consistent with some players having self-identified self-control problems, leading to longer and more frequent play than they would prefer, and to demand for commitment, and also with commitment devices creating a more rewarding experience, leading to longer-lasting involvement with the game. Our results suggest incentivizing or requiring commitment devices in computer games.

We report the results of a novel protocol for running online experiments using a combination of an online experimental platform in parallel with web-conferencing software in two formats—with and without subject webcams—to improve subjects’ attention and engagement. We compare the results between our online sessions with the offline (lab) sessions of the same experiment. We find that both online formats lead to comparable subject characteristics and performance as the offline (lab) experiment. However, the webcam-on protocol has less noisy data, and hence better statistical power, than the protocol without a webcam. The webcam-on protocol can detect reasonable effect sizes with a comparable sample size as in the offline (lab) protocol.

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.

Some economic interactions are based on trust, others on monetary incentives or monitoring. In the tax compliance context, the monitoring approach creates compliance based on audits and fines (enforced compliance), in contrast to the trust-based (voluntary compliance) approach, which is based on taxpayers’ willingness to comply. Here, we examine how changes in taxation regarding platform economy revenues affect intended labor supply on such platforms. New EU legislation, effective from 2023, will mandate data sharing between platforms and tax authorities across Europe, thus resulting in increased monitoring. We investigate how this upcoming shift in monitoring power affects the intended use of platforms and how it may interact with users’ trust. We use a survey among platform workers (N = 626) in the Netherlands to examine views of the proposed regulation change, corrected for the proportion of platform income and several measures of trust. We experimentally manipulate information by either informing participants about the upcoming monitoring change or not. Results show that informing respondents about the change negatively affects expected supply of labor, and this effect is independent of respondents’ trust. We discuss the policy implications of these results.

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.

We conducted a large-scale online experiment to examine whether climate change messaging can induce emotions and motivate pro-environmental action. We study how exposure to explicit positive (‘warm glow’) and negative (‘cold prickle’) emotional appeals as well as a traditional social norm communication affects pro-environmental action. We find that a simple call to take action to mitigate climate change is at least as affective as social norm message framing and emotional appeals. Our results highlight the difficulty of designing messaging interventions that effectively harness emotional incentives to promote pro-environmental action. Messages that explicitly emphasise the personal emotional benefits of contributing to environmental causes or the adverse emotional effects of not doing so seem to fall short of motivating pro-environmental effort. Our findings underscore the need for caution when incorporating emotive appeals into policy interventions.

We use an online experiment to study the relative effect on voter behavior of a candidate’s voice pitch and policy stance. We demonstrate a strong voice-pitch bias: between candidates who are identical in every other aspect, voters are more likely to choose the one with the lower voice-pitch, and more so in elections between men than women candidates. We then introduce a novel phenomenon: persistence of voice-pitch bias is the amount of policy difference needed to compensate for voice-pitch bias. While persistence is also gender-dependent, the effect is now reversed: voice-pitch bias is more persistent in elections between women than men candidates. As a possible mechanism, we show that voters perceive candidates with lower voice-pitch as more competent and trustworthy.

Increasingly, experimental research is being conducted on the Internet in addition to the laboratory. Online experiments are more convenient for subjects and researchers, but we know little about how the choice of study location affects data quality. To investigate whether respondent behavior differs across study location, we randomly assign subjects to participate in a study in a laboratory or in an online setting. Contrary to our expectations, we find few differences between participants in terms of the level of attention and socially desirable responding. However, we find significant differences in two areas: the degree of self-reported distractions while completing the questionnaire and the tendency to consult outside sources for answers to political knowledge questions. We conclude that when the greater convenience (and higher response rates) of online experiments outweighs these disadvantages, Internet administration of randomized experiments represent an alternative to laboratory administration.