Besides environmental shocks/policies as the drivers of gentrification, the public sector can play an important role in neighborhood transformation by investing in physical infrastructure, structuring land-use decisions, and incentivizing local business, impacting residents' choice in both the housing market and labor market. This project investigates the role of public transportation investment (new rail transit lines) on neighborhood gentrification. The massive investment in metro rail transit aims to reduce congestion and pollution, to improve transit access to regional amenities and work opportunities. It can also spur housing appreciation and labor market expansion, which induces residents' re-optimization in both the housing and labor markets. Evidence shows that the construction of new metro rail lines increases public transportation users in both tracts with new metro rail stations and tracts with interacting metro rail stations, increases local housing prices, and expands residents' choice set in the labor market. This paper will further develop a structural model to investigate residents' re-optimization in both the housing market and labor market corresponding to neighborhood changes induced by transportation improvements to access the potential distributional impacts of transportation infrastructure improvement on residents' welfare.