Online-to-offline advertisements as field experiments

Online advertisements have become one of today’s most widely used tools for enhancing businesses partly because of their compatibility with A/B testing. A/B testing allows sellers to find effective advertisement strategie,s such as ad creatives or segmentations. Even though several studies propose a technique to maximize the effect of an advertisement, there is insufficient comprehension of the customers’ offline shopping behavior invited by the online advertisements. Herein, we study the difference in offline behavior between customers who received online advertisements and regular customers (i.e., the customers visits the target shop voluntary), and the duration of this difference. We analyze approximately three thousand users’ offline behavior with their 23.5 million location records through 31 A/B testings. We first demonstrate the externality that customers with advertisements traverse larger areas than those without advertisements, and this spatial difference lasts several days after their shopping day. We then find a long-run effect of this externality of advertising that a certain portion of the customers invited to the offline shops revisit these shops. Finally, based on this revisit effect findings, we utilize a causal machine learning model to propose a marketing strategy to maximize the revisit ratio. Our results suggest that advertisements draw customers who have different behavior traits from regular customers. This study demonstrates that a simple analysis may underrate the effects of advertisements on businesses, and an analysis considering externality can attract potentially valuable customers.

Welfare economics of managing an epidemic: an exposition

This paper reviews recent findings on the normative analysis of private and governmental countermeasures against infectious diseases, focusing on COVID-19. Based on a model that relates the economic activity to infectious disease epidemics, policies that maximize social welfare are considered. Lockdowns in many countries are measures that restrict economic activity over a wide area, and the economic damage they cause is extremely large. Existing studies on the net benefit of lockdown implemented in 2020 have reached mixed conclusions as to whether it is warranted or not. Although the estimates of costs and effects are relatively stable, the setting of the value of a statistical life for converting effects into benefits has a wide range and is also likely to overestimate benefits. Therefore, a careful procedure for setting is particularly crucial to obtain a reliable evaluation of countermeasures. Compared to uniform restriction of activities, taking measures to restrict activities by selecting targets may improve efficiency. Attributes that can be used to select targets include those that can be identified at little or no cost, such as age and industry, and those that can only be identified at a cost, such as close contact with infectious individuals and the presence of pathogens. In comparison to lockdown, these measures may reduce human suffering and economic suffering. No trade-off exists between uniform activity restrictions and selective activity restrictions.

Distance to news: how social media information affects bribe-giving in India

While recent empirical evidence reveals some effective interventions in preventing corruption among bureaucrats and politicians, there has been little discussion on how to prevent the bribe-giving behavior of ordinary citizens. This paper investigates the role of social media information in influencing the supply of bribes by citizens instead of the demand side. We, therefore, developed and published an original news application in India and implemented a 3-month experiment. In this application, we randomly circulate live news related to corruption to users and incorporate a lab experiment into the app system to elicit users’ bribery behavior every week. We find that corruption news involving politicians within a close geographical proximity lowers users’ moral costs against the anti-social bribery act, leading to an increase in the amount of bribes. However, news of accused citizens and officials within the geographic proximity increases their moral cost against bribes and decreases the amount. This suggests that individually tailored local information on corruption may be an effective tool to reduce citizens’ supply of bribes.

Job stress and mental health among social workers: evidence from a field experiment at a public employment support institution in Japan

This study examines the causal effects of job stress on workers’ mental health. Evaluating the causal relationship between job stress and workers’ mental health is challenging due to an endogeneity problem, as heavy workloads and thus job stress are likely assigned to workers in good mental health condition. Endogeneity can also be problematic due to workers’ unobserved heterogeneity, such as personal capacities and stress resistance, which are associated with both job stress and mental health outcomes. To solve this problem, we conduct a field experiment at a public employment support institution in Japan. In the experiment, we randomly assign counsellors to jobseekers who are visiting the institution for the first time. Since jobseekers experience varying levels of difficulty finding work, this random assignment results in unexpected workloads, adding job stress for counsellors. We then collect counsellors’ daily records on mental health conditions for 4 consecutive weeks, matching the responses with the random assignment data on job counselling. Utilising a panel structure of the dataset and applying a fixed-effects model, we remove counsellors’ time-invariant unobserved heterogeneities. We measure counsellors’ mental health in terms of both subjective, self-reported perceptions and objective aspects of blood pressure and pulse. The results reveal that the job stress driven by newly assigned problematic jobseekers deteriorates aspects of counsellors’ objective mental health, whereas it does not appear to affect their subjective mental health. This result suggests that workers can accumulate the negative effects of job stress on mental health that they may be unaware of.