Department of Economics
Julis Romo Rabinowitz Building
Princeton, NJ 08544-1021
Institutional Affiliation: University of California at San Diego
NBER Working Papers and Publications
|February 2020||A Method to Construct Geographical Crosswalks with an Application to US Counties since 1790|
with , , : w26770
Empirical researchers often have to map data provided for a "reporting" spatial unit, say counties in 1900, to a "reference" one, say, counties in 2010. We discuss a general method to create such crosswalks: computing the share of the area of each reporting unit nested in a given reference unit. Using these shares, data can be re-aggregated from the reporting to the reference units. We apply the method to construct a crosswalk for US county-level data since 1790 to present-day counties or commuting zones. We also provide the code to generate other crosswalks given maps of reporting and reference units.
|January 2020||Imputing Missing Values in the US Census Bureau's County Business Patterns|
with , , : w26632
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 in practice: (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.