This page will always contain a link to the most up-to-date version of the standard GTAP Model, a global
computable general equilibrium model. The model code will reflect any
changes or refinements to the standard model which are introduced subsequent to publication of the GTAP Book.
All modifications are noted with the version information at the top of the TAB file.
For those new to the GTAP Model who want to learn more about how to use the models and programs we strongly
encourage you to attend a short course, although the website offers numerous resources for self-learning - a
good place to start would be the overview, which has links to resources documenting
the GTAP Model.
Various issues relating to the model are also regularly discussed on the
GTAP-L mailing list. The answers to several
frequently asked questions about the model have been retained. The
model is implemented using the GEMPACK software suite and
RunGTAP.
This release adds a revised version of geelas, a program for computing general equilibrium price
elasticities, following the approach described in chapter 5 of the
GTAP Book. The revised geelas accommodates multiple
margins sectors, a feature of the GTAP Data Base since release 5. Other files are unchanged.
This new release fixes 3 bugs found in the previous GTAP.TAB version 6.0 released in June 2001. They are
in the equations computing summary variables and may cause errors in the main model when users implement
simulations with one of the following specifications:
The current model version is GTAP.TAB Version 6.0. This represents the most substantial set of
changes to GTAP.TAB since the publication of the GTAP book (version 2.2 of GTAP.TAB). A summary of all
post version 2.2 changes, along with downloads, is also available on this site.
What's new in Version 6.0?
The first set of changes undertaken in the past year were largely organizational, having the goal of grouping
the model into eight self-contained "modules" capturing the key components of GTAP.TAB. By reorganizing
the TAB file in this way, it facilitates modifications of the model, since variables are grouped with the
equations in which they are used, and cross-module variables are identified as such.
In addition to these organizational changes, the introduction of multiple transport margins activities
into the version 5 Data Base necessitated revision of the international transport sector theory. These
modifications are encompassed in the version 5.0 GTAP.TAB file which was used in the August, 2000, GTAP Short
Course.
These most recent changes are motivated by GTAP Technical
Paper No. 20, authored by Robert McDougall on new regional household demand system.
Both McDougall's work and the recent GTAP Technical Paper No.
19, by Kevin Hanslow have proposed changes to the welfare decomposition module in GTAP. These are
related to the changes in the regional household demand system, but they go much further. Indeed, these have
addressed all known limitations associated with the original welfare decomposition proposed by Huff and Hertel
in GTAP Technical Paper No. 5.
