Publication
Accepted, Journal of Development Economics
Abstract: Historically, the debate on judicial independence has been centered on whether the participation of external branches in the appointment process of judges hampers the impartial administration of justice. However, less attention has been given to how the internal judicial organization shapes the judge's decision. This paper, which focuses on the Indian lower judiciary, explores whether the prospects of promotion to higher courts result in currying favor with judicial leaders who possess discretionary power over personnel matters within the judicial organization. For this purpose, I exploit natural experiments: female judicial leader's appointments replacing male incumbents, causing the unpredictable shift of gender preferences in personnel evaluation of local judges. Then, I use the triple difference strategy exploiting the high-court level variation on whether it has at least one female judicial leader, the individual judge level variation on the eligibility as the high court judge, and the temporal variation pre- and post-female judicial leader's appointment. Estimation results show that eligible judges pander to female leaders and hand down lenient sentences on female parties. Evidence suggests that discretionary appointments of judges through the non-transparent "judges-selecting-judges" system can be detrimental to the independent administration of justice. Therefore, careful institutional design is necessary to balance judicial accountability and independence.
(joint with Yuko Mori, R Manjula, D Rajasekhar, and Takashi Kurosaki) World Development, 2025, Volume 188
Abstract: Broad representation and competent leaders are both important factors when selecting representatives in a democracy. While gender quotas aim for the equal representation of genders, it is a challenge for non-elite women to become politicians in the context of elite dominance. In such cases, equal representation between social classes may be impeded. Gender quotas may also make the selection of competent leaders difficult if the number of qualified women is limited and if the opportunity cost of becoming a politician is high for such women. This study explores the random assignment of gender quotas across villages in India to examine the impact of gender quotas on the broadness of representation and the competence of candidates. We conducted a field survey in villages and collected information about cognitive and non-cognitive related skills and the socioeconomic backgrounds of the voters and candidates in local elections. We find that female candidates with higher cognitive skills are more positively selected among voters compared to male candidates, while households with less leadership experience can participate in elections as candidates in a gender quota system. These results suggest that the quota system could have the potential to promote broad political participation and encourage meritocratic candidate selection.
(joint with Takahiro Matsui) Marine Policy, 2025, Volume 177
Abstract: Since Hardin (1968) emphasized the fundamental difficulties of common pool resource (CPR) management, social scientists have been struggling to find a way of mitigating a free-riding problem in social dilemma situations. Empirical evidence based on a public goods experiment demonstrates that introducing a punishment opportunity among subjects successfully solves the free-riding problem. However, few studies investigate whether the effectiveness of such a punishment option varies with community network structures. To examine this aspect, we targeted 10 Japanese fishing communities and conducted public goods games. During the course of the experiments, we exogenously changed the rule of the game and introduced punishment opportunities. Adopting the difference-in-differences strategy, we compare individual contributions between closed and open community structures before and after the introduction of the punishment opportunity. Estimation results find that the punishment option is counterproductive in the closed communities because it crowds out existing cooperative norms. This implies that policies without considering local community structures may exacerbate CPR management problems.
(joint with Yuko Mori, D Rajasekhar, R Manjula, Takashi Kurosaki), Economic Development and Cultural Change, 2024, Vol.73(1), pp.451-486.
Abstract: Gender quotas are intended to address the underrepresentation of women in government. However, their effectiveness is still debated. We explore the random assignment of gender quotas across villages in India to investigate whether women members of local councils affect public good allocation in their constituencies. We conducted a field survey in 100 villages with populations of approximately 400 each, constituency size for which only one council member is elected for representation. We find that the performance of women council members is generally the same as men members in public good allocation, except for a lower performance by women in delivering water facilities. We suggest that the influence of non-member actors such as husbands, lower levels of educational achievement, and lower electoral incentive as obstacles that women members face. We also find that the gender and castes of the council president affects the performance of women council members.
(joint with Takashi Kurosaki, Yuko Mori), Japanese Economic Review, 2022, 73:179–209
Selected for the 2022 JER Best Article Award
Abstract: 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 three-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.
Economics Bulletin, 2013, Vol. 33 No. 4 pp. 2874-2889.
Abstract: This study aims to provide empirical evidence on the economic and social impacts of access to microloans disbursed through self-help group (SHG) programs. For this purpose, primary data were collected from households in Kerala, South India, and combined with detailed financial transactions of SHG members and information collected through laboratory experiments. The estimation results show that wealthier group members are significantly more likely to reap economic benefits, probably from productive investments. For poor members, asset accumulation and consumption smoothing are the two main pathways out of poverty through SHG-modeled microfinance initiatives. Finally, we find that reciprocal cooperation and trust among group members are developed by repeated social interactions, which are facilitated by weekly meetings of SHGs.
Working Paper
Building a National Identity Rooted in Democratic Values Among Political Leaders: Evidence from the Pro-democracy Movement in Taiwan (joint with Miri Aoki)
Abstract: Political elites, who shape the fundamental pillars of the state, are becoming increasingly divided. Some advocate democratic ideals and inclusive institutions, while others are resolutely devoted to autocratic governance. What originates these fundamentally opposed ideological commitments? This paper examines the long-term influence of early-life exposure to the pro-democracy movement on shaping collective identity and fostering a commitment to democratic governance among political elites. We focus on the 1979 Kaohsiung Incident in Taiwan—a historic event in which peaceful demonstrations turned into violent suppression. Using a triple-differences design combined with a Natural Language Processing approach, we find that legislators who were in their formative years and born in Kaohsiung at the time of the Incident more consistently suggest and support democracy-oriented legislation. Furthermore, we develop a novel method of text-based identity detection and find that these political elites internalize a Taiwanese national identity that is closely associated with democratic values. Our findings suggest that localized movements and shared narratives can foster a national identity that, in turn, reinforces ideological commitments, shaping policymaking and helping societies uphold democratic norms.
The Long-Run Effects of Patriotic Education During Political Repression: Evidence From the Cultural Revolution in China
(joint with Kai Kajitani)
Abstract: Authoritarian governments have commonly adopted a patriotic education system during political repression, aimed at legitimizing their authority and mitigating citizens' dissent against political violence. We investigate the long-term impact of the patriotic educational curriculum during the nationwide turmoil of the Cultural Revolution in China. Our analysis leverages two concurrent natural experiments that occurred in the late Cultural Revolution: (i) the sudden initiation of state-led violence against civilians and (ii) the educational reform promoting patriotism in primary education. Employing a cohort difference-in-differences design, we find that early-life exposure to such patriotic indoctrination amidst state-led violence decreases the probability of having mental illnesses in adulthood. The underlying mechanism suggests that patriotic education nurtures political loyalty that legitimizes the authoritarian government and it reduces psychological burdens caused by state-led violence. However, the post-Cultural Revolution regime reversed the legitimacy of the Mao Zedong's Cultural Revolution regime and implemented a new educational curriculum. Our evidence shows that those who were exposed to conflicting education programs are more likely to suffer from mental health problems. This highlights that unsteady patriotic indoctrination due to unstable political regimes might deteriorate the young generation's long-term mental health.
"Social Approval Seeking and Misperceived Legitimization: The Roots of Toxicity in Online Communities"
(joint with Tsuyoshi Tsuru)
Abstract: Online toxicity has become a serious global concern, often intensified by platform features that encourage social validation. This paper investigates how mutual rating systems—exemplified by “like” buttons—cultivate approval-seeking behaviors that lead to increased toxicity. Leveraging two natural experiments from a major Japanese Q&A platform—(i) the introduction of a like-button feature and (ii) the subsequent integration of these ratings with monetary incentives—we use a difference-in-differences approach combined with machine learning-based toxicity measures. Intuitively, we compare how toxicity levels evolve before and after these interventions among users who are particularly sensitive to social approval versus those who are not. Our findings show that users driven by social approval become notably more toxic following these interventions, indicating that public affirmation can exacerbate harmful behaviors. We attribute this escalation to a phenomenon of “misperceived legitimization,” wherein approval-seeking individuals initially conceal their propensity for harm but then interpret visible endorsements of toxic content as widespread community acceptance, prompting them to activate their latent harmful tendencies. These findings suggest that platform features promoting social approval-seeking can drive toxicity within online communities.
"Saving for the lean season and seasonal poverty dynamics: Evidence from a randomized experiment and high-frequency data"
(joint with Kazushi Takahashi, Abu S Shonchoy, Takeshi Aida, Yu Ri Kim, Hisaki Kono, and Takashi Kurosaki)
Selected for the ADB-IEA Innovative Policy Award 2023, Honorable Mention
Abstract: Can commitment-saving (CS) ahead of a lean season alter consumption downfalls among the ultra-poor? We collected 36 rounds of bi-weekly household panel data over two-years in Bangladesh and conducted a savings experiment in the second year by randomly allocating commitment-saving (CS) products with either temporary savings subsidy with “premium”, or prevailing “market” interest rate. Premium group doubles the formal savings, resulted in increased food and non-food expenditure by 8.6-12.6% during the lean season, with no lasting post-lean season impact. Market group shows no discernable impacts. Our results suggest that, while imperfect, a better-designed savings product could potentially mitigate seasonal deprivation.
(joint with Yasuyuki Sawada and Takeshi Aida)
Abstract: Social preferences shape behavioral principles in various aspects of society. Therefore, it is important to understand the determinants of social preferences to ensure the overall efficacy of any organizations. However, little is known about how repeated daily interactions foster social preferences. This study investigates whether social interactions in the workplace affect the conformity of social preferences among workers, and whether social coherence underlies the development of fairness norms in organizations. A two-week field experiment was conducted with agricultural manual laborers in the Philippines, where team compositions and payment contracts were randomized. Additionally, lab-in-the-field experiments were conducted to measure social preferences. The results show that workers who belonged to the same group more frequently during the experiment have similar social preferences compared to those who did not belong to the same group. Moreover, workers who worked together are more likely to comply with the fifty-fifty norm in the dictator game than those who did not. Finally, we find that group-based financial incentives improve social preference conformity and the emergence of the fairness norm. These findings suggest that social interactions and incentive schemes play an important role in influencing an organization's performance by shaping their social preferences and norms.
(joint with Takashi Kurosaki, Yuko Mori)
Abstract: This paper investigates whether exposure to the extreme views of vocal minorities on social media undermines a pro-social consensus in society, focusing on corruption in India. We developed an original mobile application to randomly distribute news and blogs about corruption to users and quantify their attitudes toward corruption by applying machine learning algorithms to the opinions posted on our app. By comparing users' attitudes before and after viewing extreme articles, our estimation results show that users become more radical in reinforcing their original attitudes after viewing extreme content. Vocal minorities erode the pro-social consensus against corruption by causing polarization. The underlying mechanisms suggest that pro-attitudinal extreme information shifts users' recognition of group norms in a more extreme direction and induces users' conformity to updated group norms. In contrast, counter-attitudinal extreme information causes an emotional backlash against dissenting communities. However, this radicalization effect completely dissipates within a week once the distribution of online information is terminated within our app, implying that polarization in online society will not persist for a long time if repeated exposure to vocal minority extremism is mitigated.
(joint with Yasuyuki Sawada, Takeshi Aida, Keitaro Aoyagi)
Abstract: Rice planting contracts in the Philippines are predominantly fixed-wage (FW) although individual work–efforts are largely observable. We compare different theories which can account for the use of this seemingly inefficient contractual arrangement. We “perturbate” the existing contract and observe its consequences by adopting a hybrid experimental method of framed and lab-in-the-field experiments. While we found positive incentive effects in individual piece rate (IPR) and moral hazard problems in FW, non-monetary incentives play a significant role under FW.
Work in Progress
"Social Media, Discrimination, and Politics: Online Field Experiments in India"
Abstract: This paper provides field-experimental evidence on how repeated exposure to biased news through social media affects societal discrimination and political polarization in India. I developed and released an original mobile application in which social media news is delivered to users' mobile phones on the daily basis during the experimental period (202 days). In this application, treatment and control arms are randomly built-in. In the treatment arm, a machine learning algorithm customizes news circulation based on individual user’s past behavior on the web. In the control arm, news circulation is fully randomized. Three main findings are obtained by econometric analyses. First, the customized news circulation significantly makes an individual flow of daily news more religiously biased and politically extreme. Second, users' political beliefs and preferences toward religious discrimination are unlikely to be affected by repeated exposure to such slant news. However, if users can recognize that a majority of other users express positive opinions on the slant news, they get to be less against religious discrimination and more strongly favor political extremism. Finally, the cognitive bias rather than concerns for social reputation is a main driver of emergence of societal discrimination and political polarization.
“On the Origins and Persistence of Parochial Altruism: A Tenure Institution and Intergroup Conflicts in Colonial India”
Abstract: This paper examines historical origins and persistence of parochial altruism by exploiting natural experiments during the early modern and the colonial period (1801-1932) of South India. Theory suggests that parochial altruism composed of in-group favoritism and out-group hostility can be nurtured by repeated exposure to intergroup conflicts among socially-defined groups. Natural experiments in South India provides the suitable setting to test this theory: some communities in this region had historically adopted a randomized formation of fishing groups for each available fishing lot every year and intergroup conflicts had frequently occurred among these randomized fishing groups. All fishing groups are obligated to report any type of conflicts to religious judicial systems. I digitized detailed conflict information from 1801 to 1932 and combined it with the data from lab-in-the-field experiments for descendants. I find that an individual is more altruistic to other community members if their ancestors had more experiences of sharing a fishing group membership and more frequently sued other groups together (i.e., they shared common enemies). Furthermore, I demonstrate mechanisms through which such parochial altruism has persisted over generations.
"Judicial Independence and Economic Development" (joint with Sultan Mehmood)
"Political Term Lengths: Evidence from the Historical Natural Experiment in India" (joint with Junichi Yamasaki, Tomoko Matsumoto, Shunsuke Tsuda)
"From Classrooms to Policies: How Early-Life Environmental Education Influences Policymaking" (joint with Akio Yamazaki)
"Fairness Concerns at Work" (joint with Yasuyuki Sawada, Takeshi Aida)
"Understanding Ethical Consumption" (joint with Takahiro Matsui)
“Incentives, Self-selection, and Moral Sentiments in the Labor Contract: Field Experiments in the Philippines” (joint with Yuki Higuchi, Yasuyuki Sawada, Takeshi Aida)
"Why Institutions Fail? Experimental Evidence from Common Pool Resource Management" (joint with Keisaku Higashida, Takahiro Matsui)
“Simple Institutions and Social Norms to Escape Poverty Trap: Experimental Evidence in Ethiopia” (joint with Girum Abebe, Abebaw Zefu, Yukichi Mano)
Publications (Japanese)
Please see CV