Urban and transit planner, data analyst, app-maker, and recently former USDOT official David Schneider created the concept of an 18-hour neighborhood to measure the vibrancy of urban life using retail around transit stations. Sunil Dasgupta talks with Schneider about his methodology, how he applied it to the Washington DC region, and the implications of his research. At dmvtransittourism.com. Music by Washington art-pop rock band Catscan!