RESEARCH

Data and materials for my papers can be accessed on the journals' website or on my OSF profile. 

Publications

Enabling or Limiting Cognitive Flexibility? Evidence of Demand for Moral Commitment (with Marta-Serra Garcia). 2023. American Economic Review, 113(2): 396-429.

Moral behavior is more prevalent when individuals cannot easily distort their beliefs self-servingly. Do individuals seek to limit or enable their ability to distort beliefs? How do these choices affect behavior? Experiments with over 9,000 participants show preferences are heterogeneous -- 30% of participants prefer to limit belief distortion, while over 40% prefer to enable it, even if costly. A random assignment mechanism reveals that being assigned to the preferred environment is necessary for curbing or enabling self-serving behavior. Third parties can anticipate these effects, suggesting some sophistication about the cognitive constraints to belief distortion.

Mis-nudging Morality (with Coby Morvinsky and On Amir). 2023. Management Science. 69(1): 464-474.

Morals constrain self-serving behavior. Yet, self-regulation failures in the face of monetary temptation are common at the workplace. To limit such failures, organizations can design environments that limit the temptation to behave self-servingly, nudging workers to uphold their morals. In a series of experiments where participants may be tempted to take excessive pay after exerting effort, we study whether a simple intervention—asking individuals to state the wage they believe should be paid ex-ante, before facing the temptation to take excessive compensation—prevents self-serving behavior. In contrast to lay beliefs and the predictions from prior work, we find that such an intervention is not effective, leading to self-serving behavior. However, a more realistic elicitation procedure of the appropriate wage mitigates this effect. These findings contribute to work on the malleability of moral behavior showing that simple interventions thought to effectively mitigate self-serving behavior can prompt individuals to stretch their moral boundaries. They also stress the importance of properly testing interventions that might seem intuitive.

The Demand for, and Avoidance of, Information (with Russell Golman, George Loewenstein and Andras Molnar). 2021. Management Science, 1.     Published online in Articles in Advice 15 Dec 2021 

Management scientists recognize that decision-making depends on the information people have, but lack a unified behavioral theory of the demand for (and avoidance of) information. Drawing on an existing theoretical framework in which utility depends on beliefs and the attention paid to them (Golman and Loewenstein, 2018), we develop and test a theory of the demand for information encompassing instrumental considerations, curiosity, and desire to direct attention to beliefs one feels good about. We decompose an individual’s demand for information into the desire to refine beliefs, holding attention constant, and the desire to focus attention on anticipated beliefs, holding these beliefs constant. Because the utility of resolving uncertainty (i.e., refining beliefs) depends on the attention paid to it, and more important or salient questions capture more attention, demand for information depends on the importance and salience of the question(s) it addresses. In addition, because getting new information focuses attention on one’s beliefs, and people want to savor good news and ignore bad news, the desire to obtain or avoid information depends on the valence (i.e., goodness or badness) of anticipated beliefs. Five experiments (N = 2; 361) test and find support for these hypotheses, looking at neutrally-valenced as well as ego-relevant information. People are indeed more inclined to acquire information: a) when it feels more important, even if it cannot aid decision-making (Experiments 1A & 2A); b) when a question is more salient, manipulated through time lag (Experiments 1B & 2B); and c) when anticipated beliefs have higher valence (Experiment 2C).

Megastudies Improve the Impact of Applied Behavioral Science (with Milkman, K.L., D. Gromet, H. Ho, J. Kay, T. Lee, P. Pandiloski, Y. Park, A. Rai, M. Bazerman, J. Beshears, L. Bonacorsi, C. Camerer, E. Chang, G. Chapman, R. Cialdini, H. Dai, L. Eskreis-Winkler, A. Fishbach, J.J. Gross, A. Horn, A. Hubbard, S.J. Jones, D. Karlan, T. Kautz, E. Kirgios, J. Klusowski, A. Kristal, R. Ladhania, G. Loewenstein, J. Ludwig, B. Mellers, S. Mullainathan, J. Spiess, G. Suri, J.H. Talloen, J. Taxer, Y. Trope, L. Ungar, K.G. Volpp, A. Whillans, J. Zinman, A.L. Duckworth). Nature, 600, 478–483 (2021). 

Policy-makers are increasingly turning to behavioural science for insights about how to improve citizens’ decisions and outcomes. Typically, different scientists test different intervention ideas in different samples using different outcomes over different time intervals. The lack of comparability of such individual investigations limits their potential to inform policy. Here, to address this limitation and accelerate the pace of discovery, we introduce the megastudy—a massive field experiment in which the effects of many different interventions are compared in the same population on the same objectively measured outcome for the same duration. In a megastudy targeting physical exercise among 61,293 members of an American fitness chain, 30 scientists from 15 different US universities worked in small independent teams to design a total of 54 different four-week digital programmes (or interventions) encouraging exercise. We show that 45% of these interventions significantly increased weekly gym visits by 9% to 27%; the top-performing intervention offered microrewards for returning to the gym after a missed workout. Only 8% of interventions induced behaviour change that was significant and measurable after the four-week intervention. Conditioning on the 45% of interventions that increased exercise during the intervention, we detected carry-over effects that were proportionally similar to those measured in previous research. Forecasts by impartial judges failed to predict which interventions would be most effective, underscoring the value of testing many ideas at once and, therefore, the potential for megastudies to improve the evidentiary value of behavioural science.

Return to Normalcy? Lifestyle and Mental Health One Year into COVID-19 (with Osea Giuntella, Paolo Barbieri, and Sally Sadoff), Scientific Reports, 11, 23349 (2021). https://doi.org/10.1038/s41598-021-02702-4. 

In previous work, Giuntella et al. (2021), we documented large disruptions to physical activity, sleep, time use and mental health among young adults at the onset of the COVID-19 pandemic in Spring 2020. This study explores the trends 1 year into COVID-19, as vaccines began to roll out, COVID-19 deaths declined, and social distancing measures eased in the United States. We combine biometric and survey data from multiple cohorts of college students spanning Spring 2019 through Spring 2021 (N = 1179). Our results show persistent impacts of the pandemic on physical activity and mental health. One year into the pandemic, daily steps averaged about 6300 per day compared to about 9800 per day prior to the pandemic, a 35% decline. Almost half of participants were at risk of clinical depression compared to a little over one-third prior to the pandemic, a 36% increase. The impacts on screen time, social interactions and sleep duration at the onset of COVID-19 largely dissipated over the course of the pandemic, though screen time remained significantly higher than pre-pandemic levels. In contrast to the sharp changes in lifestyle and mental health documented as the pandemic emerged in March 2020, we do not find evidence of behavioral changes or improvements in mental well-being over the course of Spring 2021 as the pandemic eased.

Behavioral Nudges Increase COVID-19 Vaccinations: Two Randomized Controlled Trials (with Hengchen Dai, Maria Han, Lily Roh, Naveen Raja, Sitaram Vangala, Hardikkumar Modi, Shital Pandya, Daniel Croymans), Nature (2021) https://doi.org/10.1038/s41586-021-03843-2 (*Equal Lead Author with Hengchen Dai)

Enhancing vaccine uptake is a critical public health challenge. Overcoming vaccine hesitancy and failure to follow-through on vaccination intentions requires effective communication strategies. We present two sequential randomized controlled trials (RCTs) to test the impact of behavioral interventions on COVID-19 vaccine uptake. We designed text-based reminders that make vaccination salient and easy, and delivered them to patients of a healthcare system one day (first RCT; N=93,354, clinicaltrials #NCT04800965) and eight days (second RCT; N=67,092, NCT04801524) after they received notification of vaccine eligibility. The first reminder boosted appointments and vaccination rates within the healthcare system by 6.07 (84%) and 3.57 (26%) percentage points, respectively; the second reminder increased those outcomes by 1.65 and 1.06 percentage points, respectively. The first reminder was more impactful when it made patients feel the vaccine was already theirs. However, we find no evidence that combining it with an information intervention addressing vaccine hesitancy heightened its effect. Online studies (N=3,181) examining vaccination intentions reveal divergent patterns from the first RCT, underscoring the importance of pilot-testing interventions in the field. These findings inform the design of behavioral nudges for promoting health decisions5, highlighting the value of making vaccination easy and inducing feelings of ownership. 

A Megastudy of Text-Message Nudges Encouraging Patients to Get Vaccinated at an Upcoming Doctor's Appointment (with Milkman, K.L., M Patel., L. Gandhi, H. Graci, D. Gromet, H. Ho, J. Kay, T. Lee, M. Akinola, J. Beshears, J.E. Bogard, A. Buttenheim, C.Chabris, G. Chapman, J. Choi, H. Dai, C. Fox, A. Goren, M. Hilchey, J. Hmurovic, L. John, D. Karlan, M. Kim, D. Laibson, C. Lamberton, B. Madrian, M. Meyer, M. Modanu, J. Nam, T. Rogers, R. Rondina, M. Shermohammed, D. Soman, J. Sparks, C. Warren, M. Weber, R. Berman, C. Evans, C. Snider, E. Tsukayama, C. Van den Bulte, K. Volpp K., A. Duckworth), Proceedings of the National Academy of Sciences, 2021, 118(20). 

Many Americans fail to get life-saving vaccines each year, and the availability of a vaccine for COVID-19 makes the challenge of encouraging vaccination more urgent than ever. We present a large field experiment (N=47,306) testing 19 udges delivered to patients with text message and designed to boost adoption of the influenza vaccine. Our findings suggest text messages sent prior to a primary care visit can boost vaccination rates by up to 11%. Overall, interventions performed better when they were a) framed as reminders to get flu shots that were already reserved for the patient and b) congrunt with the sort of communications patients expected to receive from their healthcare privider (i.e., not surprising, casual or interactive). The best-performing intervention in our study reminded patients to get their flu shot at their upcoming doctor's appointment and indicated it was reserved for them. This successful script could be used as a template for campaigns to encourage the adoption of life-saving vaccines, including against COVID-19. 

Lifestyle and Mental Health Disruptions During COVID-19 (with Osea Giuntella, Kelly Hyde and Sally Sadoff), available at https://www.pnas.org/content/118/9/e2016632118, Proceedings of the National Academy of Sciences, 2021, 118(9). 

Using a longitudinal dataset linking biometric and survey data from several cohorts of young adults before and during the  pandemic (N=682), we document large disruptions to physical activity, sleep, time use, and mental health. At the onset of the pandemic, average steps decline from 10,000 to 4,600 steps per day, sleep increases by  25-30 minutes per night, time spent socializing declines by over half to less than 30 minutes, and screen time more than doubles to over 5 hours per day. Over the course of the pandemic from March to July 2020, the proportion of participants at risk of clinical depression ranges from 46\% to 61\%, up to a 90 percent increase in depression rates compared to the same population just prior to the pandemic. Our analyses suggest that disruption to physical activity is a leading risk factor for depression during the pandemic. However, restoration of those habits through a short-term intervention does not meaningfully improve mental well-being.

Nudging Generosity in Consumer Elective Pricing (with Charis Li, Anya Samek and Ayelet Gneezy), Organizational Behavior and Human Decision Processes, 2021, 163, 91-104, available at https://www.sciencedirect.com/science/article/pii/S0749597818306538

Consumer elective pricing (CEP)—allowing each consumer to decide how much to pay for a product or service—is becoming widespread. Organizations using this pricing scheme for both commercial and non-profit purposes have adopted a wide variety of phrasings to communicate it. In this paper, we propose that seemingly negligible differences in the phrasing of CEP can substantially increase payments and donations. In three field experiments in both charitable and commercial marketplaces, we vary the language used to describe a CEP appeal to either highlight the social aspect of the exchange or not. Our findings show that CEP phrasing that cues the social nature of the transaction elicits socially-oriented considerations and nudges generosity in both the non-profit and for-profit markets. Follow-up online studies shed light on consumers’ perceptions under different CEP phrasing and establish a boundary condition.

Bribing the Self (with Uri Gneezy, Marta Serra-Garcia, and Roel van Veldhuizen), Games and Economic Behavior, 2020, 120(3), pp. 311-324. CESifo Working Paper Number No. 8065, available at https://www.cesifo.org/DocDL/cesifo1_wp8065.pdf

Expert advice is often biased in ways that benefit the advisor. We demonstrate how self-deception helps advisors be biased while preserving their self-image as ethical and identify limits to advisors’ ability to self-deceive. When advisors learn about their incentives before evaluating the available investments, they are more likely to be biased than when they learn about their incentives only after privately evaluating the invest- ments. Consistent with self-deception, advisors are more likely to believe their advice is what the client would prefer and to subsequently choose the incentivized investment for themselves when learning about their incentives before evaluating the investments. Biased advice persists with minimal justifications but is eliminated when all justifi- cations are removed. These findings show how self-deception can be constrained to improve advice provision.

Bribery: Behavioral Drivers of Distorted Decisions (with Uri Gneezy and Roel van Veldhuizen),  Journal of the European Economic Association, 2019, 17(3), pp.917-946.

We experimentally investigate behavioral drivers of bribery, focusing on the role of self- interest, reciprocity, and moral costs associated with distorting judgment. In our experiment, two participants compete for a prize; a referee picks the winner. Participants can bribe the referee. When the referee can keep only the winner’s bribe, bribes distort her judgment. When the referee keeps the bribes regardless of the winner, bribes no longer influence her decision. A field experiment in an Indian market confirms these results. These findings imply that our participants are influenced by bribes out of self-interest, and not because of a desire to reciprocate. Further evidence shows that self-interest guides decisions to a greater extent when referees have scope for avoiding the moral costs associated with distorting judgment. As a result, limiting referees’ ability to form self-serving evaluations can significantly reduce the effectiveness of bribes. 

On the size of the Gender Difference in Competitiveness (with Uri Gneezy and Aniela Pietraz), Management Science, 2018, vol 64(4), pp. 1541-1554. 

We design a new procedure for measuring competitiveness and use it to estimate the magnitude of the gender gap in competitiveness. Before working on a task, participants choose what percentage of their payoffs will be based on a piece-rate compensation scheme; the rest of their payoff is allocated to a competitive compensation scheme. This novel procedure allows us to distinguish between 101 different levels of competitiveness, as opposed to the binary measure used in the literature. While the binary measure allows researchers to conclude that about twice as many men than women choose to compete (typically 2/3 versus 1/3 respectively), the new procedure sheds light on the intensive margin. We find that the intensity of the preference is more extreme than the binary measure could detect. For example, we find that only one-fifth of the most competitive 25 percent of our participants are women, and the most competitive 10 percent of our participants are all men. The new procedure also allows us to study the correlation between competitiveness and parameters such as overconfidence, attitudes toward risk and ambiguity.

Deception and Reciprocity (with Gonul Dogan and Despoina Alempaki), Experimental Economics, 2019, 22(4), pp.980-1001.

We experimentally investigate the relationship between (un)kind actions and subsequent deception in a two-player, two-stage game. The first stage involves a dictator game. In the second-stage, the recipient in the dictator game has the opportunity to lie to her counterpart. We study how the fairness of dictator-game outcomes affects subsequent lying decisions where lying hurts one’s counterpart. In doing so, we examine whether the moral cost of lying varies when retaliating against unkind actions is financially beneficial for the self (selfish lies), as opposed to being costly (spiteful lies). We find evidence that individuals engage in deception to reciprocate unkind behavior: The smaller the payoff received in the first stage, the higher the lying rate. Intention-based reciprocity largely drives behavior, as individuals use deception to punish unkind behavior and truth-telling to reward kind behavior. For selfish lies, individuals have a moral cost of lying. However, for spiteful lies, we find no evidence for such costs. Taken together, our data show a moral cost of lying that is not fixed but instead context-dependent.

A Must Lie Situation: Avoiding Giving Negative Feedback (with Uri Gneezy, Christina Gravert, and Franziska Tausch).  Games and Economic Behavior, 2017, vol 102, pp. 445-454. 

We examine under what conditions people provide accurate feedback to others. We use feedback regarding attractiveness, a trait people care about, and for which objective information is hard to obtain. Our results show that people avoid giving accurate face-to-face feedback to less attractive individuals, even if lying in this context comes at a monetary cost to both the person who gives the feedback and the receiver. A substantial increase of these costs does not increase the accuracy of feedback. However, when feedback is provided anonymously, the aversion to giving negative feedback is reduced.     

Working papers

Field Tested: Assessing the Transferability of Behavioral Interventions (with Hengchen Dai, Maria Han, Sitaram Vangala, Juyea Hoo & Jeffrey Fujumoto), Forthcoming at Nature Human Behavior

Image Concerns and Generosity: Field Evidence and Predictions (with Minah Jung*, Ayelet Gneezy and Leif Nelson), R&R at Management Science

Sleep: Educational Impact and Habit Formation (with Osea Giuntella and Sally Sadoff), under review

Assessing Nudge Scalability: Two Lessons from Large-Scale RCTs (with Hengchen Dai, Maria Han, Naveen Raja, Sitaram Vangala & Daniel Croymans), under review 

Provide Information or Encourage Follow-Through? Effects of Behavioral Interventions Depend on Baseline Motivation (with Ilana Brody, Hengchen Dai, Katherine Milkman, Mitesh Patel, and Angela Duckworth), under review

The Impact of Joint versus Separate Prediction Mode on Forecasting Accuracy (with Alex Imas, Minah Jung, and Joachim Vosgerau), under review

Signals of Virtue and When they Backfire (with Stephanie Permut and Gretchen Chapman), under review

How Close is Too Close: The Effect of Near-Losses on Subsequent Risk Taking (with Stephanie Permut, Julie Downs and George Loewenstein), under review

Lying for Image (with Kai Barron and Agne Kajackaite), under review 

Near-Miss Deterrence: Incorporating Near-Miss Effects into Deterrence Theory (with Stephanie Permut, Julie Downs and George Loewenstein), working paper

Do Fines Deter Lying? Varying the Size and Probability of Punishment (with Uri Gneezy and Katharina Laske), working paper

Arbitrage or Narrow Bracketing? On Using Money to Measure Intertemporal Preferences (with Jim Andreoni, Christina Gravert, Michael Kuhn, Yang Yang), working paper.