Natalie J. Yang

Research

Working papers

Estimating demand for bike-shares with stockouts (Jan 2023)

How many more bike-share trips would be taken if bikes and docks could always be available to commuters who want them? In this paper, I develop a method for estimating demand in the presence of stockouts and apply it to study New York City’s bike-share system. My results indicate that on average, demand for a given bike-share trip would be twice as high if stockouts could be eliminated. I find that when bike-share trips are stocked out, the vast majority of customers choose not to take bike-share at all rather than substitute to an alternative in-stock trip; substitution to other trips accounts for only 1 percent of lost demand due to stockouts. Back-of-the-envelope estimates suggest that eliminating bike-share stockouts for just the month of my study period would have reduced polluting emissions significantly, including NO emissions by 8 percent. I show that stockouts are a major barrier preventing bike-shares from serving as a viable mode of sustainable urban transportation.

Imputing Missing Values in the US Census Bureau's County Business Patterns (Jan 2021) (Data files) - w/ Fabian Eckert, Teresa C Fort, and Peter K Schott

The County Business Patterns data published by the US Census Bureau track employment by county and industry from 1946 to the present. Two features of the data limit their usefulness to researchers: (1) employment for the majority of county-industry cells is suppressed to protect confidentiality, and (2) industry classifications change over time. We address both issues. First, we develop a linear programming method that exploits the large set of adding-up constraints implicit in the hierarchical arrangement of the data to impute missing employment. Second, we provide concordances to map all data to a consistent set of industry codes. Finally, we construct a user-friendly, 1975 to 2016 county-level panel that classifies industries according to a consistent set of 2012 NAICS codes in all years.

Works-in-progress

The political economy of congestion pricing: Evidence from London

Other articles

Do young people have the skills to compete in a global market? (22 June 2016) - Education Policy Institute, London