PEP 1-1 model

Long Name
PEP Standard Computable General Equilibrium Model Single-Country, Static Version
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The PEP 1-1 model (1 period – 1 country) is a static general equilibrium model that emerged from a collaboration between Bernard Decaluwe, André Lemelin, Véronique Robichaud, and Hélène Maisonnave. The model is designed for the study of an archetypal national economy. It will enable researchers to develop a relatively standard model and apply it easily to their own country, whatever the particular structure of their social accounting matrix (SAM).

The PEP 1-1 model is different from Decaluwé, Martens, and Savard’s EXTER model, which has been used extensively in the past by PEP researchers. The model distinguishes several categories of factors (labor and capital). It also takes into account all possible transfers between agents and a large set of tax instruments. Furthermore, the aggregate output of each industry consists of several products, consistent with non-square input-output tables.The authors have written the GAMS code in a general form in order to facilitate the application of the model to a broader set of aggregated SAMs.

The GAMS codes of PEP 1-1 model are available to AGRODEP members.

Download the GAMS codes.

The following additional resources are available to AGRODEP members:

  • Overview  of the PEP model (PEP 1-1.pdf) 200 slides that provides a full description of the model.
  • User guide (PEP 1-1 User Guide.pdf) presents a brief description of the model and explains in detail how to implement it in GAMS.
  • Debugator (debugator.pdf) shows how to debug a computable general equilibrium model in GAMS. It provides useful tips to debug the most common errors (calibration, compilation, execution, and specification errors) that users may encounter when running GAMS codes. The model used for all applications is the static version of the PEP model (PEP1-1). The ZIP file ( contains 20 GAMS files corresponding to the 20 examples that are presented in the core document.

You can also find the AGRODEP technical note, "a comparison between the PEP 1-1 model and the IFPRI standard model", giving a brief comparison between two models widely used by economists for policy analysis: the PEP 1-1 model and the IFPRI standard model.

A new version (2.1) of the model is now available on the PEP website. The principal changes include a reformulation of the GDP deflator, an introduction of new real (volume) variables, an external excel file which contains the exogenous parameters and a new calibration procedure of the quantity demanded of the composite commodity.

Disclaimer: All these materials are freely available to AGRODEP members for individual use with acknowledgment to AGRODEP. They should not be distributed to non-AGRODEP network members and may not be transformed, altered, or used for commercial purposes. Readers who have questions and comments about the documents may contact Veronique Robichaud at the following address: or Hélène Maisonnave at:

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Use Policy
May not be distributed to non AGRODEP Network Members.