    Welcome to RunGTAP, the program for interactively solving the GTAP model of the Global Trade Analysis Project. For instructions on how to use the program, see the on-line Help.  You can press F1 at any time to get context-specific help. Or print out and study the detailed tutorial document, Ho2K.DOC, which is supplied with the program. 

    The GTAP model is a multiregion, applied general equilibrium model, with perfect competition and constant returns to scale.  Bilateral trade is handled via the Armington assumption. Innovations include: the treatment of private household preferences using the non-homothetic CDE functional form, explicit international trade and transport margins, and a global banking sector which links global savings and investment. GTAP also gives users a wide range of closure options, including a selection of partial equilibrium closures that facilitate comparison of results to studies based on partial equilibrium assumptions.

    For more information about the GTAP model and project, see the book "Global Trade Analysis: Modeling and Applications" edited by Thomas W. Hertel (Cambridge University Press, 1997), and visit the GTAP web site: www.agecon.purdue.edu/gtap/  Enquiries about GTAP should be directed to Professor Hertel, Department of Agricultural Economics, Purdue University (full address in on-line Help).

    This version of RunGTAP is designed to work with the Version 5 GTAP model and data, released in 2000. These incorporate a more detailed treatment of international trade margins, and other enhancements.

    GTAP is formulated and solved using GEMPACK, a flexible system for solving AGE models. RunGTAP is simply a visual interface to various GEMPACK programs. GEMPACK (General Equilibrium Modelling PACKage) is a suite of general-purpose economic modelling software especially suitable for general equilibrium models. It can handle a wide range of economic behaviour and also contains powerful capabilities for viewing data and analysing results. See the GEMPACK Web site at:  http://www.monash.edu.au/policy/gempack.htm

    RunGTAP users are automatically provided with a number of useful pieces of auxiliary information, under the View drop-down menu, when they run the model in this environment. The first is the output of the GTAPVIEW program, which organizes the data in a way that is quite useful for viewing critical economic features. By using ViewHAR's facilities for creating row, column, and matrix shares, the user can quickly obtain information such as a given country's share of consumption in GDP, or the cost share of electricity in iron and steel production.
    Secondly, after each simulation, a complete welfare decomposition is provided based on the work of Huff and Hertel, as documented in GTAP technical paper #5 (available on the GTAP web site listed below). To obtain this decomposition after running a simulation, simply go to "view|updated data|welfare decomposition". The resulting header array file permits the user to break down the regional equivalent variation into its component parts, including changes due to allocative efficiency, terms of trade, improved technology and endowments.
    In addition to the welfare decomposition, users automatically get the volume results associated with the equilibrium percent changes in output. These may be obtained by going to "view|updated data|volume changes". These may be interpreted as volume changes measured in millions of US dollars at base period prices.
    This version of RunGTAP introduces several new features:
* A "subtotals" feature that allows you to partition the total effect of a group of shocks between the individual shocks.
* The ability to construct and use different variants of the supplied GTAP model from within the RunGTAP interface.

