要旨：2011年3月に発生した東日本大震災は、日本に多大なる被害をもたらした。そして、その予想を上回る被害の大きさは、被災地住民に物理的かつ精神的なショックを与えた。こうした大規模な自然災害は、人々の選好、および、意思決定を変化させる可能性があると考えられる。そこで、本研究は出生率に焦点を当て、東日本大震災による人々の意思決定への影響を検証することを目的とする。そのため、市区町村のパネルデータを用いて、Difference-in-Differenceにより、震災前後の出生に関わる意思決定の変化を推定した。その結果、被災地はそうでない地域と比較して出生率が有意に減少したことが分かった。

要旨：This paper proposes a new approach to estimate willingness-to-pay (WTP) for each attribute of alternatives. Our approach is based on a new conjoint-survey experiment design (Hainmueller, et., al. 2013) and empirical welfare-analysis (Bhattacharya 2015), which allows us to nonparametrically estimate the distribution of WTP without strong assumptions on individual preference. Moreover, if the utility is assumed as the quasi-linear form, the lower and upper bounds of the average WTP can be estimated with limited sample size. We illustrate our approach with the conjoint-survey data on Japanese young workers. Our estimation results show that they have higher WTP for working location, promotion opportunity, transfer, and over-time workings than other attributes.

要旨：Analysis of the urban agglomeration of economic activity has focused on its benefits for firm productivity. But the marginal-cost savings which agglomeration brings about also free up inputs that can be used to produce higher-quality goods, with their own profitability potential. We use plant-product-level data from Japanese manufacturing to examine agglomeration’s influences on product quality. Results confirm that quality does grow with regional market size, suggesting polices aimed at encouraging urban agglomeration improve competitiveness by raising product quality as well as productivity. Total factor productivity alone, therefore, underestimates agglomeration benefits by ignoring the quality incentives that accompany it.

要旨：Measuring the degree of competition in markets is essential for policy and decision makers. Commonly used structural indices (e.g., HHI) overlook the way in which firms compete, and hence their prices setting in markets. We propose a new measure: the Schedule (Temporal) Differentiation Metric, STDM, which encapsulates firms' market shares as well as the degree of overlap and substitution between their competing services. We demonstrate the STDM using aviation markets and discover a significant improvement in explaining price levels and structure. The information captured by the STDM also explains fares across fare percentiles depending on the competing airlines' business models.

要旨：We develop a two-region model in an overlapping-generations economy with longevity. In our model, we assume household decisions of the number of children and residential location. We examine the relation between life expectancy and spatial agglomeration. Our calibration shows that longer life expectancy promotes agglomeration. Results show that the imbalance of the population distribution between urban and rural area increases as longevity increases. We introduce self-healthcare behavior into the model and show that a higher contribution of self-healthcare intensifies urban agglomeration.

要旨：This study contributes to the literature on the relationship between geographical and relation-based distances of economic agents. We aim to estimate the causal effect of firm’s position in the inter-firm transaction network on its spatial location within a city. Using micro data of inter-firm financial transactions for non-retail firms in Kure, a medium-sized Japanese city, we demonstrate that the more central firms in transaction networks tend to have smaller inter-firm distances and therefore to locate at more accessible places within the city. We estimate that one standard deviation increase in PageRank network centrality implies a decrease of 0.154 standard deviation in the interfirm distance (about 457 meters).