Carsharing station location and demand: Identification of associated factors through Heckman selection models

Abstract

Carsharing services have been introduced as new mobility options in metropolitan areas worldwide. In order for the new mobility option to operate successfully and attract sufficient demand to sustain service, it is imperative to understand where carsharing stations should be located and what factors are important for bolstering demand. To provide insights for this understanding, this study attempts to identify factors that influence carsharing operators' selection of carsharing station locations and demand based on one-month rental transaction data in Seoul, South Korea. Identification is conducted by relating location selection and demand to underlying characteristics of specific census blocks in which reported carsharing stations are located. Comparative analyses are also conducted by segmenting the transaction data into subsets: 1) workday and non-workday rentals and 2) rentals made by age groups of members in their 20se30s and 40s and older. To correct the selection bias (carsharing rentals are observed only where carsharing stations are located), Heckman selection models are applied to jointly explain the selection of station locations and demand. The estimated models suggest that the supply level of public transit service is positively related to both location selection for carsharing stations and demand. Meanwhile, population density is negatively associated with both selection and demand. A rather weak association between carsharing station location and demand by members in their 40s and older are found, suggesting that carsharing operators mainly target young users when selecting carsharing service locations.