@TechReport{iza:izadps:dp17154,
            	author={Millimet, Daniel L.},
            	title={(Don't) Walk This Way: The Econometrics of Crosswalks},
            	year={2024},
	month={Jul},
            	institution={Institute of Labor Economics (IZA)},
            	address={Bonn},
            	type={IZA Discussion Paper},
            	number={17154},
            	url={https://www.iza.org/index.php/publications/dp17154},
	abstract={It is increasingly common in empirical research to merge data sets containing different units of observation. When the units are not nested, a crosswalk specifying how the units from one data source are allocated to the units of the other is needed. Unfortunately, most crosswalks are ad hoc, a fact that is often ignored by researchers and has not caught the attention of econometricians. Here, I show that use of an incorrect crosswalk induces measurement error that is necessarily nonclassical and can be consequential. I discuss and illustrate the ramifications of using a flawed crosswalk, present two specification tests, offer potential solutions, and provide an application to the effects of social media on political polarization.},
	keywords={crosswalk;nonclassical measurement error;social media;polarization},
            }