The compact support property for the Λ\Lambda-Fleming-Viot process with underlying Brownian motion

Using the lookdown construction of Donnelly and Kurtz we prove that, at any fixed positive time, the $\Lambda$-Fleming-Viot process with underlying Brownian motion has a compact support provided that the corresponding $\Lambda$-coalescent comes down from infinity not too slowly. We also find both upper bound and lower bound on the Hausdorff dimension for the support.Comment: 21 page

The Supplemental Nutrition Assistance Program and Nutrient Intakes

The socioeconomic determinants of Food Stamp Program participation and the effects of program participation on nutrient intakes are investigated, using data from the 2003–04 and 2005–06 National Health and Nutrition Examination Survey (NHANES). An endogenous switching regression system of equations is estimated, which includes protein, vitamin A, vitamin C, calcium and iron. Participation in the FSP is found to play an important role in nutrient intakes. Socio-demographic variables such as income, household size and presence of children are also found to affect individuals’ decisions on program participation and nutrient intakes.Food Consumption/Nutrition/Food Safety, Food Security and Poverty,

Tax Policy and Entrepreneurship

Small businesses and the entrepreneurial spirit are among the driving forces in economic growth and development in the United States. The US governments (both federal and state) have long been aware of the importance of entrepreneurship, and many policies are directed toward helping small businesses. However, whether such policies give rise to expected behavioral responses from small businesses remains inconclusive. This dissertation looks into the behavioral response of self-employed filers to individual income tax and the impact of state and federal tax policies on entrepreneurship. In the first chapter, we examine taxpayers’ behavioral response to the Alternative Minimum Tax (AMT). We find strong evidence that taxpayers, especially self-employed individuals, appear to manipulate their incomes to avoid the AMT. We also find suggestive evidence that the notch created by the AMT generates both a real response and an evasion response. These results have important policy implications for the AMT design and for the evaluation of the welfare loss from taxation of small businesses. The second chapter examines the effect of state tax policies on entrepreneurial activity. This paper contributes to the literature in several important ways: first, we explore dynamic specifications to capture inherent time trends among entrepreneurial performance. Second, we consider a number of intensive-margin measures of state nonfarm proprietors’ success. Our paper is the first to use nonfarm proprietors’ income as a direct measure of entrepreneurial success at the state level. We investigate several measures of small business performance derived from nonfarm proprietors’ income and employment data. Third, we extend the earlier research by including a longer panel (1978-2009) of state data. Despite these innovations, our empirical results echo the recent studies in this area and suggest that most of the highly-visible state tax policies do not have statistically significant impacts on entrepreneurial performance. The last chapter uses time series analysis to explore the effect of federal tax policies on entrepreneurial performance and whether the effect is heterogeneous across different stages of the business cycle. We do not find that tax policy affects the small businesses sector differently between economic ups and downs

Effects of Supplemental Nutrition Assistance Program on Nutrient Intakes

The socioeconomic determinants of participant in the Supplemental Nutrition Assistance Program (SNAP) and effects of the program on nutrient intakes are investigated. The dependent variable is transformed by logarithm which facilitates estimation of the model. Marginal effects of explanatory variables are calculated which make interpretation of the effects of explanatory variables easier. The result suggests SNAP plays a significant role in nutrient intakes. The effects of participation in SNAP are negative on vitamin C and positive on all other nutrients (protein, vitamin A, vitamin C, calcium, and iron), for males, females, and both genders combined. Income, household size, presence of children, and other socio-demographic variables all affect individuals’ decisions on program participation and nutrient intakes. Results suggest the effects of socio-demographic variables are very different, in signs and magnitudes, between the participants and non-participants. These differentiated effects of socio-demographic variables are likely to be masked by the use of a more conventional model (such as the single or multiple equation treatment effect models) and highlight the importance of using the Switching System Regression