While various incentives have been provided to promote carpooling, the share of car-pooling has remained flat over the years. In this project, we quantify various factors that affect carpooling in a measure called matching cost, and study how matching cost affects the commuting patterns in a mixed mode corridor with both drive-alone and various forms of car-pooling modes. Measures of commuting cost, Vehicle-Miles-Traveled (VMT), and equity will be obtained from the developed model to assess the effectiveness of various policies towards car-pooling.