Trade Theory in Computable General Equilibrium Models
Armington, Krugman and Melitz
For computable general equilibrium (CGE) modelers, the book shows how Melitz-style CGE models can be calibrated, solved and interpreted. A major practical contribution of the book is to show how large-scale Armington models such as GTAP can be converted to Melitz by the addition of a small number of equations and minimal alteration of the original Armington model.
The book describes computational experience in solving Melitz CGE models using GEMPACK software. This experience will be of interest to researchers currently attempting to solve Melitz-based CGE models. Almost all previous Melitz studies have used GAMS software. Authors of these studies have reported computational difficulties. These difficulties did not occur in this book’s GEMPACK-based computations.
The book concludes that: (a) CGE modelers can embrace Melitz while retaining their Armington-based models as powerful interpretive devices; and (b) via GEMPACK, large-scale CGE models incorporating Melitz specifications can be solved with no more difficulty than similar-dimensioned Armington models.
Chapter 1. Introduction: What’s in the Book and How to Read It.- Chapter 2. Armington, Krugman and Melitz as Special Cases of an Encompassing Model.- Chapter 3. Optimality in the Armington, Krugman and Melitz Models.- Chapter 4. Calibration and Parameter Estimation for a Melitz Sector in a CGE Model.- Chapter 5. Melitz equals Armington Plus Endogenous Productivity and Preferences.- Chapter 6. Illustrative GEMPACK Computations in a General Equilibrium Model with Melitz Sectors.- Chapter 7. Converting an Armington Model into a Melitz Model: Giving Melitz Sectors to GTAP.- Chapter 8. Summary and Concluding Remarks.