Graduate Student in the Social SciencesThe impact of pharmaceutical marketing on physician prescribing: Evidence from academic medical center policy changes.
Joint with Ian Larkin, Desmond Ang, and Tina WuSummary: We examined the effect of detailing visits by pharmaceutical salespeople on the prescribing habits of physicians. We compared prescribing decisions of physicians at medical centers that restricted detailing to prescribing decisions of physicians at centers that had no restrictions. By examining medical centers that restricted different types of detailing activities, we can distinguish between the psychological and informational effects of detailing on physician prescribing.
Giving to receive: Selfish giving and why it works.
This study is funded by a grant from the Russell Sage FoundationAbstract: Many firms and charities use free giveaways to encourage purchases or donations respectively. This study uses a laboratory experiment to test whether people reciprocate to such gifts because they infer positive intentions (as economic models suggest), or if they reciprocate in order to uphold their social image. I find that people will reciprocate to a gift-giver's intention to give a gift, even when a third-party prevents the transaction from occurring. I also find that people are less likely to reciprocate if their actions are obscured from others, suggesting that social image is also crucial to reciprocity. Finally, I find that people infer similar intentions behind both cash and non-cash gifts, and that people only reciprocate marginally more to gifts of much higher value. These results all hold when controlling for the distribution of wealth and items between all players. These findings shed insight into the mechanisms behind reciprocity and also carry important strategic implications for organizations that use gifts to lure clients.
Why do goal-based incentives cause cheating? Unpacking the confounding effects of goals, social comparisons and pay.
Joint with Ian LarkinAbstract: Studies suggest that goal-based incentives can increase worker cheating on simple tasks. However, these previous results cannot distinguish whether this increased cheating is due to the goals themselves or to concurrent changes in other elements of the incentive system, such as marginal pay or information about peer performance. We used a carefully-designed 2x2x2 experiment that compared cheating caused by pay (pay-for-performance or not), incentive structure (goal-based or not), and framing (peer comparison language or not). We found no increase in cheating due to using goals. Pay-for-performance and peer comparisons both increased cheating. We found no evidence of interaction effects between conditions. Our results suggest that scholars should focus on each individual feature of an incentive system when comparing different incentive systems, such as goals and piece-rates.
Reducing dissonance via non-Bayesian updating: An axiomatic model.
Joint with Matthew KovachAbstract: Standard preference theory assumes that the act of choosing can reveal one's preferences but cannot actually alter those preferences. However, evidence in psychology suggests that people prefer their past and present choices to reflect consistency. If so, then a past choice can directly influence an individual's current choice. This paper adapts the standard model of preferences over acts in order to account for this possibility; when new information is made available to an agent, the agent updates his preferences using a non-Bayesian approach that maximizes the consistency between his past choices and his current choice. This differs from standard status quo bias, since the past choices need not be default or status quo options. This model can provide an axiomatic framework for explaining a number of observed empirical results across many fields, such as in voter behavior and consumer brand loyalty.
For further details, to obtain copies, or to learn about follow-up studies to any of the above, please e-mail me at mchao@caltech.edu.
Some papers may not be available due to journal embargo policies.
All of my research is graciously supported by the National Science Foundation through a Graduate Research Fellowship in Economics.