Fuzzy differences in differences
AbstractDifference in differences require that 0% of observations are treated in the control group and during period 0 (no "always takers") and 100% in the treatment group in period 1 (no "never takers"). Sometimes, the treatment rate increases more in the treatment than in the control group but there are never or always takers. This paper develops results to identify treatment effects in such settings. They only require one common trend assumption on the outcome of interest Y whereas the standard instrumental variable result also requires common trend on treatment D. I derive bounds for treatment effects which are tight when there are no or few always takers. This can be the case in applications considering the effect of an innovation, where by definition no observations are treated in period 0. I derive other bounds that are tight when the treatment rate does not change much between the two periods in the control group, which can be the case in applications considering the extension of a program to a group previously not eligible. I use my results to measure the efficacy of a new drug for smoking cessation.
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 HAL in its series PSE Working Papers with number halshs-00671368.
Date of creation: Feb 2012
Date of revision:
Note: View the original document on HAL open archive server: http://halshs.archives-ouvertes.fr/halshs-00671368
Contact details of provider:
Web page: http://hal.archives-ouvertes.fr/
Difference in Differences ; Heterogeneous Treatment Effect ; Imperfect Compliance ; Partial Identification ; Smoking Cessation;
Other versions of this item:
- C21 - Mathematical and Quantitative Methods - - Single Equation Models; Single Variables - - - Cross-Sectional Models; Spatial Models; Treatment Effect Models
- C23 - Mathematical and Quantitative Methods - - Single Equation Models; Single Variables - - - Models with Panel Data; Spatio-temporal Models
- I19 - Health, Education, and Welfare - - Health - - - Other
This paper has been announced in the following NEP Reports:
- NEP-ALL-2012-02-27 (All new papers)
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.:
- Meyer, Bruce D, 1995.
"Natural and Quasi-experiments in Economics,"
Journal of Business & Economic Statistics,
American Statistical Association, vol. 13(2), pages 151-61, April.
- Jorg Stoye, 2009.
"More on Confidence Intervals for Partially Identified Parameters,"
Econometric Society, vol. 77(4), pages 1299-1315, 07.
- Jörg Stoye, 2008. "More on confidence intervals for partially identified parameters," CeMMAP working papers CWP11/08, Centre for Microdata Methods and Practice, Institute for Fiscal Studies.
- Charles F. Manski, 1997.
"Monotone Treatment Response,"
Econometric Society, vol. 65(6), pages 1311-1334, November.
- Erica Field, 2005. "Property Rights and Investment in Urban Slums," Journal of the European Economic Association, MIT Press, vol. 3(2-3), pages 279-290, 04/05.
- Victor Chernozhukov & Sokbae 'Simon' Lee & Adam Rosen, 2012.
"Intersection bounds: estimation and inference,"
CeMMAP working papers
CWP33/12, Centre for Microdata Methods and Practice, Institute for Fiscal Studies.
- Victor Chernozhukov & Sokbae 'Simon' Lee & Adam Rosen, 2011. "Intersection bounds: estimation and inference," CeMMAP working papers CWP34/11, Centre for Microdata Methods and Practice, Institute for Fiscal Studies.
- Victor Chernozhukov & Sokbae 'Simon' Lee & Adam Rosen, 2009. "Intersection Bounds: estimation and inference," CeMMAP working papers CWP19/09, Centre for Microdata Methods and Practice, Institute for Fiscal Studies.
- William N. Evans & Jeanne S. Ringel, 1997.
"Can Higher Cigarette Taxes Improve Birth Outcomes?,"
NBER Working Papers
5998, National Bureau of Economic Research, Inc.
- Evans, William N. & Ringel, Jeanne S., 1999. "Can higher cigarette taxes improve birth outcomes?," Journal of Public Economics, Elsevier, vol. 72(1), pages 135-154, April.
- Battistin, Erich & Rettore, Enrico, 2008. "Ineligibles and eligible non-participants as a double comparison group in regression-discontinuity designs," Journal of Econometrics, Elsevier, vol. 142(2), pages 715-730, February.
- Andrews, Donald W.K. & Guggenberger, Patrik, 2010. "ASYMPTOTIC SIZE AND A PROBLEM WITH SUBSAMPLING AND WITH THE m OUT OF n BOOTSTRAP," Econometric Theory, Cambridge University Press, vol. 26(02), pages 426-468, April.
- Hoyt Bleakley & Aimee Chin, 2004. "Language Skills and Earnings: Evidence from Childhood Immigrants," The Review of Economics and Statistics, MIT Press, vol. 86(2), pages 481-496, May.
- Field, Erica Marie, 2005. "Property Rights and Investment in Urban Slums," Scholarly Articles 3634150, Harvard University Department of Economics.
- Nada Eissa & Jeffrey B. Liebman, 1995.
"Labor Supply Response to the Earned Income Tax Credit,"
NBER Working Papers
5158, National Bureau of Economic Research, Inc.
- Eissa, Nada & Liebman, Jeffrey B, 1996. "Labor Supply Response to the Earned Income Tax Credit," The Quarterly Journal of Economics, MIT Press, vol. 111(2), pages 605-37, May.
- Joshua D. Angrist & William N. Evans, 1996.
"Children and Their Parents' Labor Supply: Evidence from Exogenous Variation in Family Size,"
NBER Working Papers
5778, National Bureau of Economic Research, Inc.
- Angrist, Joshua D & Evans, William N, 1998. "Children and Their Parents' Labor Supply: Evidence from Exogenous Variation in Family Size," American Economic Review, American Economic Association, vol. 88(3), pages 450-77, June.
For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: (CCSD).
If references are entirely missing, you can add them using this form.