Testing for Separation in Agricultural Household Models and Unobservable Household-Specific Effects
When market structure is complete, factor demands by households will be independent of their characteristics, and households will take their production decisions as if they were profit-maximizing firms. This observation constitutes the basis for one of the most popular empirical tests for complete markets, commonly known as the “separation” hypothesis. In this article, we show that most existing tests for separation using panel data are potentially biased towards rejecting the null-hypothesis of complete markets, because of the failure to adequately control for unobservable household-specific effects. Since the variables on which the test for separation is based cannot be identifed in most panel datasets following the usual covariance transformations, and are likely to be correlated with the household-specific effect, neither the within nor the variance-components procedures are able to solve the problem. We show that the Hausman-Taylor 1981 estimator, in which the impact of covariates that are invariant along one dimension of a panel can be identifed through the use of covariance transformations of other included variables that are orthogonal to the household-specific effects as instruments, provides a simple solution. Our approach is applied to a rich Tunisian dataset in which separation –and thus the null of complete markets– is strongly rejected using the standard approach, but is not rejected once correlated unobservable household-specific effects are controlled for using the Hausman-Taylor instrument set.
|Date of creation:||18 Jan 2011|
|Note:||View the original document on HAL open archive server: https://halshs.archives-ouvertes.fr/halshs-00557188|
|Contact details of provider:|| Web page: https://hal.archives-ouvertes.fr/|
References listed on IDEAS
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.:
- Bowlus, Audra J. & Sicular, Terry, 2003. "Moving toward markets? Labor allocation in rural China," Journal of Development Economics, Elsevier, vol. 71(2), pages 561-583, August.
- Michael R. Carter & Pedro Olinto, 2003.
"Getting Institutions “Right” for Whom? Credit Constraints and the Impact of Property Rights on the Quantity and Composition of Investment,"
American Journal of Agricultural Economics,
Agricultural and Applied Economics Association, vol. 85(1), pages 173-186.
- MICHAEL R. CARTER & Pedro Olinto, 2000. "Getting Institutions 'Right' for Whom: Credit Constraints and the Impact of Property Rights on the Quantity and Compostiton of Investment," Wisconsin-Madison Agricultural and Applied Economics Staff Papers 433, Wisconsin-Madison Agricultural and Applied Economics Department.
- Carter, Michael R. & Olinto, Pedro, 2000. "Getting Institutions 'Right' for Whom: Credit Constraints and the Impact of Property Rights on the Quantity and Compostiton of Investment," Staff Paper Series 433, University of Wisconsin, Agricultural and Applied Economics.
- Sarah Gavian & Marcel Fafchamps, 1996. "Land Tenure and Allocative Efficiency in Niger," American Journal of Agricultural Economics, Agricultural and Applied Economics Association, vol. 78(2), pages 460-471.
- Cornelis Gardebroek & Alfons Oude Lansink, 2003. "Estimating Farm Productivity Differentials using Panel Data: The Hausman-Taylor Approach," Journal of Agricultural Economics, Wiley Blackwell, vol. 54(3), pages 397-415.
- Hall, Alastair R & Rudebusch, Glenn D & Wilcox, David W, 1996. "Judging Instrument Relevance in Instrumental Variables Estimation," International Economic Review, Department of Economics, University of Pennsylvania and Osaka University Institute of Social and Economic Research Association, vol. 37(2), pages 283-298, May.
- Alastair R. Hall & Glenn D. Rudebusch & David W. Wilcox, 1994. "Judging instrument relevance in instrumental variables estimation," Finance and Economics Discussion Series 94-3, Board of Governors of the Federal Reserve System (U.S.).
- Hausman, Jerry A & Taylor, William E, 1981. "Panel Data and Unobservable Individual Effects," Econometrica, Econometric Society, vol. 49(6), pages 1377-1398, November.
- Hausman, Jerry A. & Taylor, William E., 1981. "Panel data and unobservable individual effects," Journal of Econometrics, Elsevier, vol. 16(1), pages 155-155, May.
- J. A. Hausman & W. E. Taylor, 1980. "Panel Data and Unobservable Individual Effects," Working papers 255, Massachusetts Institute of Technology (MIT), Department of Economics.
- Deininger, Klaus & Olinto, Pedro, 2000. "Why liberalization alone has not improved agricultural productivity in Zambia : the role of asset ownership and working capital constraints," Policy Research Working Paper Series 2302, The World Bank.
- Baltagi, Badi H & Khanti-Akom, Sophon, 1990. "On Efficient Estimation with Panel Data: An Empirical Comparison of Instrumental Variables Estimators," Journal of Applied Econometrics, John Wiley & Sons, Ltd., vol. 5(4), pages 401-406, Oct.-Dec..
- Hahn, Jinyong & Hausman, Jerry, 2002. "Notes on bias in estimators for simultaneous equation models," Economics Letters, Elsevier, vol. 75(2), pages 237-241, April.
- Benjamin, Dwayne, 1992. "Household Composition, Labor Markets, and Labor Demand: Testing for Separation in Agricultural Household Models," Econometrica, Econometric Society, vol. 60(2), pages 287-322, March.
- Eswaran, Mukesh & Kotwal, Ashok, 1986. "Access to Capital and Agrarian Production Organisation," Economic Journal, Royal Economic Society, vol. 96(382), pages 482-498, June.
- Griliches, Zvi & Hausman, Jerry A., 1986. "Errors in variables in panel data," Journal of Econometrics, Elsevier, vol. 31(1), pages 93-118, February.
- Zvi Griliches & Jerry A. Hausman, 1984. "Errors in Variables in Panel Data," NBER Technical Working Papers 0037, National Bureau of Economic Research, Inc.
- Benjamin, Dwayne, 1995. "Can unobserved land quality explain the inverse productivity relationship?," Journal of Development Economics, Elsevier, vol. 46(1), pages 51-84, February.
- H. Baltagi, Badi & Heun Song, Seuck & Cheol Jung, Byoung, 2001. "The unbalanced nested error component regression model," Journal of Econometrics, Elsevier, vol. 101(2), pages 357-381, April.
- Michael R. Carter & Yang Yao, 2002. "Local versus Global Separability in Agricultural Household Models: The Factor Price Equalization Effect of Land Transfer Rights," American Journal of Agricultural Economics, Agricultural and Applied Economics Association, vol. 84(3), pages 702-715.
- Michael Kevane, 1996. "Agrarian Structure and Agricultural Practice: Typology and Application to Western Sudan," American Journal of Agricultural Economics, Agricultural and Applied Economics Association, vol. 78(1), pages 236-245.
- Jean-Jacques Laffont & Mohamed Salah Matoussi, 1995. "Moral Hazard, Financial Constraints and Sharecropping in El Oulja," Review of Economic Studies, Oxford University Press, vol. 62(3), pages 381-399.
- Laffont, Jean-Jacques & Matoussi, Mohamed Salah., 1988. "Moral Hazard, Financial Constraints and Sharecropping in El Oulja," Working Papers 667, California Institute of Technology, Division of the Humanities and Social Sciences.
- Feder, Gershon & Lau, Lawrence J. & Lin, Justin Y. & Xiaopeng Luo, 1991. "Credit's effect on productivity in Chinese agriculture : a microeconomic model of disequilibrium," Policy Research Working Paper Series 571, The World Bank.
- Breusch, Trevor S & Mizon, Grayham E & Schmidt, Peter, 1989. "Efficient Estimation Using Panel Data," Econometrica, Econometric Society, vol. 57(3), pages 695-700, May.
- Hanan G. Jacoby, 1993. "Shadow Wages and Peasant Family Labour Supply: An Econometric Application to the Peruvian Sierra," Review of Economic Studies, Oxford University Press, vol. 60(4), pages 903-921.
- Lopez, Ramon E., 1984. "Estimating labor supply and production decisions of self-employed farm producers," European Economic Review, Elsevier, vol. 24(1), pages 61-82.
- Cornwell, Christopher & Rupert, Peter, 1988. "Efficient Estimation with Panel Data: An Empirical Comparison of Instrumental Variables Estimators," Journal of Applied Econometrics, John Wiley & Sons, Ltd., vol. 3(2), pages 149-155, April.
- Feder, Gershon, 1985. "The relation between farm size and farm productivity : The role of family labor, supervision and credit constraints," Journal of Development Economics, Elsevier, vol. 18(2-3), pages 297-313, August.
- Barrett, Christopher B., 1996. "On price risk and the inverse farm size-productivity relationship," Journal of Development Economics, Elsevier, vol. 51(2), pages 193-215, December.
- Tadashi Sonoda & Yoshihiro Maruyama, 1999. "Effects of the Internal Wage on Output Supply: A Structural Estimation for Japanese Rice Farmers," American Journal of Agricultural Economics, Agricultural and Applied Economics Association, vol. 81(1), pages 131-143. Full references (including those not matched with items on IDEAS)
When requesting a correction, please mention this item's handle: RePEc:hal:wpaper:halshs-00557188. See general information about how to correct material in RePEc.
For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: (CCSD)
If you have authored this item and are not yet registered with RePEc, we encourage you to do it here. This allows to link your profile to this item. It also allows you to accept potential citations to this item that we are uncertain about.
If references are entirely missing, you can add them using this form.
If the full references list an item that is present in RePEc, but the system did not link to it, you can help with this form.
If you know of missing items citing this one, you can help us creating those links by adding the relevant references in the same way as above, for each refering item. If you are a registered author of this item, you may also want to check the "citations" tab in your profile, as there may be some citations waiting for confirmation.
Please note that corrections may take a couple of weeks to filter through the various RePEc services.