主要从事劳动经济学，公共经济学，福利保障h而国际商务等方面的研究。

已发表论文：

Si, X. and Leonard, T. (2020), Aging out of Women Infant and Children: An Investigation of the Compensation Effect of Private Nutrition Assistance Programs. Econ Inq, 58: 446-461.

Shuval, K., Si, X., Nguyen, B. T., & Leonard, T. (2015). Utilizing Behavioral Economics to Understand Adherence to Physical Activity Guidelines Among a Low-Income Urban Community. Journal of Physical Activity and Health, 12(7), 947-953.