APAP Microcomputer Tool No. 3: GESS, A Multiple Commodity Supply and Demand Model. Analysis of Taxation and Subsidy Policies

摘要

Sound agricultural policy requires a means of estimating the impacts of various taxes and subsidies upon production and consumption levels, farm income, government costs and revenues, the balance of trade, etc. The Generalized Econometric Spreadsheet Simulation (GESS) model has been specifically designed to aid in answering such policy questions. The model essentially consists in editing well-documented tables of input information. A basic knowledge of elasticities and supply and demand theory is helpful in understanding and interpreting the results of the various simulated policy options. The main body of the document provides a complete description of the GESS modeling concept and a review of the economic theory on which it is based. Appendix A provides a detailed discussion of how to develop a prototype GESS model using LOTUS 1-2-3. Instructions and a sample set of data and parameters are provided to enable the user to program a three-commodity GESS model.