In recent years, microsimulation, which is simulation analysis using microdata, has been used to evaluate policy reforms in many countries. However, the literature on microsimulation that considers changes in individual household behavior is limited, especially for developing countries. Therefore, this study examines the change of welfare and labor supply under the simulation scenarios of income tax reform in Thailand using microsimulation. The contribution of our study is that it is among the first to apply microsimulation to analyze the personal income tax reform of a semi-developed country like Thailand. Our simulation analyses suggest an intriguing possibility that the tax revenue could be more than double without utility loss and a high fluctuation of the income after-tax. The tax reform is now in progress in Thailand. Hence, this study has reform implications for the government.
This paper aims to disclose the demographic factors of change of migrants （in-migrants and out-migrants） after 1980s, with Tokyo ward area as a target. In this paper, it has been attempted to clarify the demographic mechanism of “re-centralization” by decomposing change of migrants to population structure factor and mobility factor, by applying the method of indirect standardization. Three major ﬁndings are obtained. First, the expansion of net migrants in Tokyo ward area was mainly brought by a decline of out-migration mobility at the beginning, but an increase of in-migration mobility gradually had great impact. Second, in-migration mobility of Tokyo ward area was increasing from all prefectures after mid of 1990s, while out-migration mobility of the area was decreasing to all prefectures. Although net-migration mobility increasing from prefectures in Kansai area was high, those from surrounding prefectures were relatively low. Third, population structure factor has a certain influence on both in-migrants change and out-migrants change. This suggests the possibility of net-migrants reduction of Tokyo ward area in the future. If we are to understand the change of migration tendency correctly, it would be indispensable to analyze the mobility of both in-migration and out-migration.
Unlike recent Western societies, the proportion of nonmarital childbearing is very low in Japan, but it is increasing. Since the Longitudinal Surveys of Babies in the 21st Century, with a large sample size including about 600 babies born to unmarried parents, allow us to evaluate the home environment and circumstances of children outside marriage, I review findings and discussions concerning children outside marriage for mainly the US and Japan, then, using individual data of the surveys above, I describe demographic features of nonmarital babies, their parental characteristics, economic circumstances, mothers’ networks, and fathers’ involvement of childrearing, comparing these with children born in marital relationships. In situations of children born to unmarried parents, it is more likely than their counterparts to be the first birth, to live in urban areas, to have low birth weight babies, to have parents who smoke, to be economically disadvantageous, to have mothers with limited social networks, and to have a small number of playmates. The proportion of zero-year-old babies outside marriage who live with their father is below one in three. The proportion is lower than a half in the US. Although the survey does not include enough information on nonresident fathers, general supports from fathers to nonmarital children seem to be limited. On the other hand, a certain number of children live with their father in a stable relationship and their mothers’ socioeconomic status is very high. Regardless of the marital status of mothers, resident fathers’ involvement with childcare is almost the same. Although, on average, children outside marriage in Japan are disadvantaged, there is a range of variations.