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New Area- and Population-based Geographic Crosswalks for U.S. Counties and Congressional Districts, 1790-2020

Principal Investigator(s): View help for Principal Investigator(s) Andreas Ferrara, University of Pittsburgh; Patrick A. Testa, Tulane University; Liyang Zhou, University of Pittsburgh

Version: View help for Version V2

Name	File Type	Size	Last Modified
crosswalks			09/17/2021 06:26:PM
replication-files			09/17/2021 06:46:PM
teaching-material			10/18/2021 09:26:AM
readme.docx	application/vnd.openxmlformats-officedocument.wordprocessingml.document	15 KB	10/18/2021 05:26:AM

Project Citation:

Ferrara, Andreas, Testa, Patrick A., and Zhou, Liyang. New Area- and Population-based Geographic Crosswalks for U.S. Counties and Congressional Districts, 1790-2020. Ann Arbor, MI: Inter-university Consortium for Political and Social Research [distributor], 2021-10-18. https://doi.org/10.3886/E150101V2

Project Description

Summary: A common problem in applied research involves harmonizing geographic units across time or different levels of aggregation. We provide crosswalks that allow researchers i) to harmonize U.S. county boundaries over time across Census decades and ii) to generate congressional district level variables from county-level data. The crosswalks include an area-based approach as in Hornbeck (2010), as well as the new population-based methods from Ferrara, Testa, and Zhou (2021), which are based on granular sub-county population information. We also provide teaching material to demonstrate the utility of these new crosswalks.

Reference:
Ferrara, A., Testa, P.A., and Zhou, L. (2021) "New Area- and Population-based Geographic Crosswalks for U.S. Counties and Congressional Districts, 1790-2020", CAGE Working Paper No. 588

Scope of Project

Geographic Coverage: USA

Time Period(s): 1790 – 2020

Universe: U.S. counties and congressional districts

Data Type(s): geographic information system (GIS) data

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