Erschienen:
Cambridge, Mass: National Bureau of Economic Research, 2019
Erschienen in:NBER working paper series ; no. w25726
Umfang:
1 Online-Ressource; illustrations (black and white)
Sprache:
Englisch
DOI:
10.3386/w25726
Identifikator:
Reproduktionsnotiz:
Hardcopy version available to institutional subscribers
Entstehung:
Anmerkungen:
System requirements: Adobe [Acrobat] Reader required for PDF files
Mode of access: World Wide Web
Beschreibung:
Many econometric models used in applied work integrate over unobserved heterogeneity. We show that a class of these models that includes many random coefficients demand systems can be approximated by a "small-σ" expansion that yields a linear two-stage least squares estimator. We study in detail the models of product market shares and prices popular in empirical IO. Our estimator is only approximately correct, but it performs very well in practice. It is extremely fast and easy to implement, and it is "robust" to changes in the higher moments of the distribution of the random coefficients. At the very least, it provides excellent starting values for more commonly used estimators of these models