🌐ENGLISH

This paper examines the determinants of cross-sectional and lifecycle inequality using a lifecycle earnings process model that incorporates earnings mobility and non-employment risks across birth cohorts and over time. Unobserved skill prices and the variance of individual fixed effects across cohorts are the primary drivers, with unemployment risk being a key determinant of life cycle inequality. To explain the increase in the variance of fixed effects, we interpret these within a Roy model as realized productivity influenced by both ability and task choice. We provide evidence that technological change can amplify inequality by widening the variation in individual productivity, in addition to the standard mechanism that operates through price changes.

This paper studies how sudden losses of experienced older workers affect firm dynamics, using a natural experiment that induced unexpected early retirements. I examine the consequences of this negative labor supply shock for firm behavior, with a focus on capital investment and technology adoption. The findings indicate persistent effects, particularly among smaller firms that struggle to replace experienced older workers and increasingly rely on temporary labor. As a result, these firms reduce investment in capital and are slower to adopt new technologies, including robotics.

This study examines the impact of in-home deaths on property prices and rents in the Tokyo Metropolitan Area, Japan, utilizing unique crowd-sourced data tracking death incidents. The findings reveal a persistent 5% decline in sale prices for properties within the same building, while rent reductions are limited to the specific unit where disclosure of the incident is required. The impact varies due to the interplay between stigma surrounding death and public recognition of such incidents. A survey of homebuyers and renters reveals that the variation in effects across units is driven by differences in how informed buyers and renters are about past death incidents, rather than by differences in their preferences.

This study investigates how publicly disclosed disciplinary actions against police officers alter police organizational activities by analyzing changes in key operational indicators such as arrest counts and clearance rates. Using disciplinary actions within the Tokyo Metropolitan Police Department as a quasiexperimental framework, the study identifies a temporary but significant improvement in police performance, notably a rise in theft arrests coinciding with the public disclosure of misconduct. These findings suggest that police organizations respond to reputational threats by reallocating resources to boost visible performance metrics. The evidence points to internal incentive structures, especially promotion-related motivations among police leadership, as the primary driver of these behavioral changes.

This study examines how effectively individuals convert their resources into subjective well-being—a concept referred to as happiness efficiency—during the COVID-19 pandemic in Japan. Using representative longitudinal data from 2020 to 2023, we first estimate individual-level happiness efficiency on an annual basis. We then analyze its determinants using the conditional order-m approach. Our findings show that the fixed year effect of the pandemic was negative in the first year but turned positive in the following years. The accumulated positive effects outweighed the initial negative impact. This suggests that although individuals initially experienced an unusual decline in well-being due to various social distancing measures, they quickly adapted by learning to better utilize their socio-economic circumstances. As a result, their ability to sustain subjective well-being during the pandemic ultimately surpassed pre-pandemic levels. These findings highlight the dynamic nature of well-being under crisis conditions and underscore the importance of individual adaptability in mitigating the adverse effects of external shocks.

This paper provides causal evidence on how reducing communication costs reshapes the internal organization of problem-solving within firms. Building on Garicano’s (2000) model of hierarchical knowledge organization, we examine whether lowering communication barriers fosters vertical knowledge sharing and enhances productivity. Our empirical setting is a corporate IT support firm where employees resolve complex technical inquiries for client companies. Using wearable sensors, we capture minute-by-minute face-to-face interactions among employees before and after a leadership training program implemented to improve team communication. Exploiting this introduction of the leadership training program as an exogenous reduction in intra-team communication costs, we estimate its effects using difference-in-differences and instrumental variable analyses. We find that teams led by trained leaders exhibit a significant increase of vertical communication between junior and senior members. This substantially improves the problem-solving efficiency of junior employees. The findings provide the first causal evidence that reducing communication barriers endogenously generates hierarchical problem-solving structures, as predicted by Garicano (2000), thereby improving workplace productivity.

Long-term care is costly. About one in three Americans will experience a stay in a nursing home that exceeds 100 days during their lifetime, and about one in ten will incur out-of-pocket expenses of $200,000 or more. Surprisingly, only about 10% of retirees have private long-term care insurance. We consider alternative strategies for reforming US long-term care insurance arrangements in a quantitative structural model of the market. We find that individuals disagree about the scale of public insurance provided by Medicaid. Yet, despite differences in income, wealth, and LTC risk exposure, they agree that the secondary payer provision of Medicaid should be removed. Allowing people to top off means-tested Medicaid benefits with private long-term care insurance preserves the safety net provided by Medicaid while stimulating the private insurance market. Social welfare increases, and public expenditures on Medicaid fall.