Estimating and Testing Non-Linear Models Using Instrumental Variables
AbstractIn many empirical studies, researchers seek to estimate causal relationships using instrumental variables. When only one valid instrumental variable is available, researchers are limited to estimating linear models, even when the true model may be non-linear. In this case, ordinary least squares and instrumental variable estimators will identify different weighted averages of the underlying marginal causal effects even in the absence of endogeneity. As such, the traditional Hausman test for endogeneity is uninformative. We build on this insight to develop a new test for endogeneity that is robust to any form of non-linearity. Notably, our test works well even when only a single valid instrument is available. This has important practical applications, since it implies that researchers can estimate a completely unrestricted non-linear model by OLS, and then use our test to establish whether those OLS estimates are consistent. We re-visit a few recent empirical examples to show how the test can be used to shed new light on the role of non-linearity.
Download InfoIf you experience problems downloading a file, check if you have the proper application to view it first. In case of further problems read the IDEAS help page. Note that these files are not on the IDEAS site. Please be patient as the files may be large.
Bibliographic InfoPaper provided by National Bureau of Economic Research, Inc in its series NBER Working Papers with number 17039.
Date of creation: May 2011
Date of revision:
Note: CH ED LS
Contact details of provider:
Postal: National Bureau of Economic Research, 1050 Massachusetts Avenue Cambridge, MA 02138, U.S.A.
Web page: http://www.nber.org
More information through EDIRC
Other versions of this item:
- Lance Lochner & Enrico Moretti, 2011. "Estimating and Testing Non-Linear Models Using Instrumental Variables," University of Western Ontario, CIBC Centre for Human Capital and Productivity Working Papers 20112, University of Western Ontario, CIBC Centre for Human Capital and Productivity.
- C01 - Mathematical and Quantitative Methods - - General - - - Econometrics
- J0 - Labor and Demographic Economics - - General
This paper has been announced in the following NEP Reports:
Please report citation or reference errors to , or , if you are the registered author of the cited work, log in to your RePEc Author Service profile, click on "citations" and make appropriate adjustments.:
- Carneiro, Pedro & Heckman, James J. & Vytlacil, Edward, 2009.
"Evaluating Marginal Policy Changes and the Average Effect of Treatment for Individuals at the Margin,"
IZA Discussion Papers
4324, Institute for the Study of Labor (IZA).
- Pedro Carneiro & James J. Heckman & Edward Vytlacil, 2010. "Evaluating Marginal Policy Changes and the Average Effect of Treatment for Individuals at the Margin," Econometrica, Econometric Society, vol. 78(1), pages 377-394, 01.
- Pedro Carneiro & James J. Heckman & Edward J. Vytlacil, 2009. "Evaluating Marginal Policy Changes and the Average Effect of Treatment for Individuals at the Margin," NBER Working Papers 15211, National Bureau of Economic Research, Inc.
- Pedro Carneiro & James Heckman & Edward Vytlacil, 2009. "Evaluating marginal policy changes and the average effect of treatment for individuals at the margin," CeMMAP working papers CWP21/09, Centre for Microdata Methods and Practice, Institute for Fiscal Studies.
- Mogstad, Magne & Wiswall, Matthew, 2010. "Linearity in Instrumental Variables Estimation: Problems and Solutions," IZA Discussion Papers 5216, Institute for the Study of Labor (IZA).
- Jaeger, David A & Page, Marianne E, 1996. "Degrees Matter: New Evidence on Sheepskin Effects in the Returns to Education," The Review of Economics and Statistics, MIT Press, vol. 78(4), pages 733-40, November.
- Yitzhaki, Shlomo, 1996. "On Using Linear Regressions in Welfare Economics," Journal of Business & Economic Statistics, American Statistical Association, vol. 14(4), pages 478-86, October.
- Sergi Jiménez-Martín & Cristina Vilaplana Prieto, 2013. "Informal Care and intergenerational transfers in European Countries," Working Papers 2013-25, FEDEA.
For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: ().
If references are entirely missing, you can add them using this form.