New Nonlinear Approaches for the Adjustment and Updating of a SAM
Many structural relationships should be taken into account in any reasonable adjustment and updating process. These structural relationships are mainly represented by ratios of different types, such as technical coefficients or the proportion of the cell value in relation to its row or column total. We believe that in many cases (either because of lack of information or when the time elapsed for the estimation of a social accounting matrix is not long enough to allow for any significant structural change) the updating process should try to minimize the rela- tive deviation of the new coefficients from the initial ones in a homogeneous way. This homogeneity would mean that the magnitude of this relative deviation is similar among the elements of each row or column, therefore avoiding the concentration of the changes in particular cells of the SAM. In this work, we propose some new adjustment criteria in order to obtain a more homogeneous relative adjustment of the structural coefficients. These criteria combine the adjustment method proposed by Matuszewski et al. (1964) with other deviation functions. Each of the adjustment criteria proposed leads to a nonlinear optimization problem which is reformulated as a linear program. We test the usefulness of this proposal by comparing its results with the ones obtained by more standard approaches and we are able to show that these approaches tend to produce a less homogeneous pattern of coefficient adjustment, under certain circumstances, than the ones we put forward. Copyright Kluwer Academic Publishers 2004
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.:
- S M Macgill, 1977. "Theoretical properties of biproportional matrix adjustments," Environment and Planning A, Pion Ltd, London, vol. 9(6), pages 687-701, June.
- Golan, Amos & Judge, George G. & Miller, Douglas, 1996. "Maximum Entropy Econometrics," Staff General Research Papers 1488, Iowa State University, Department of Economics.
- Sherman Robinson & Andrea Cattaneo & Moataz El-Said, 2001.
"Updating and Estimating a Social Accounting Matrix Using Cross Entropy Methods,"
Economic Systems Research,
Taylor & Francis Journals, vol. 13(1), pages 47-64.
- Robinson, Sherman & Cattaneo, Andrea & El-Said, Moataz, 2000. "Updating and estimating a Social Accounting Matrix using cross entropy methods," TMD discussion papers 58, International Food Policy Research Institute (IFPRI).
- McDougall, Robert, 1999. "Entropy Theory and RAS are Friends," GTAP Working Papers 300, Center for Global Trade Analysis, Department of Agricultural Economics, Purdue University.
When requesting a correction, please mention this item's handle: RePEc:kap:ecopln:v:36:y:2004:i:3:p:259-272. 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: (Sonal Shukla)or (Rebekah McClure)
If references are entirely missing, you can add them using this form.