Head of Group
Economic Modeling of Agricultural Systems
PD Dr. agr., Senior Lecturer and Researcher
Nussallee 19, Haus 2, room 0.008 (ground floor)
Tel.: ++ 49 - 2 28 - 73 29 12
Wolfgang Britz is senior researcher and lecturer in a tenured position at the Institute for Food and Resource Economics, University Bonn, where his research focus is on the impacts of agricultural, environmental and trade policies on the agricultural sector, the environment and rural areas based on quantitative analysis with different types of economic simulation models. Since 2017, he heads the Economic Modelling of Agricultural Systems group after temporarily heading the "Production Economics" chair in 2016.
Complex economic models offer a wide range of options for simulation runs and return a vast amount of data, which has to be explored and exploited in various ways. The GAMS Graphical Interface Generator (GGIG) allows to operate such economic models through a Java based user interface.
GGIG was developed to generalize functionalities originally developed for CAPRI and allows to steer complex applications and to analyze their results based on tables, graphics and maps. It generates a basic Graphical User Interface for GAMS projects based on XML files.
These files define the controls for simulation runs and result exploitation. GGIG is currently used in a number of economic and agricultural modeling projects across the world. Besides GAMS, it also supports applications using the free-ware statistical package R and can also provide input for applications realized in Java. One project might also combine applications using these different languages.
GGIG is currently used e.g. in the following projects respectively modeling systems
Britz, B., Perez, I. and Gopalakrishnan B.N. (2015): Analyzing Results from Agricultural Large-scale Economic Simulation Models: Recent Progress and the Way Ahead, German Journal of Agricultural Economics 65(2): 106-119
Britz, W. (2014): A New Graphical User Interface Generator for Economic Models and its Comparison to Existing Approaches, German Journal of Agricultural Economics, 63(4): 271-285
GGIG user guide, 169 pages, Version June 2016
GGIG programming guide, 79 pages, Version June 2016
|November 2015||Network graphs added|
|October 2015||Beta testing for GTAP in GAMS with GUI based on GGIG to prepare roll-out by GTAP center|
|October 2015||Generic decomposition approach using Jacobian information from CONVERT added to "Equation and Variable viewer"|
|September 2015||OECD decides to used GGIG for official PEM release|
|September 2015||Macros, loops and if conditions in batch mode|
|August 2015||Batch mode supports parallel excecution of several GAMS tasks|
|June 2015||Table and list controls now can load information from GDX files|
|May 2015||Search fields for table columns and rows|
|May 2015||Combo boxes can now also be shown as group in own viewport with scrollbars|
|December 2014||Export to xlsx besides xls added|
|February 2015||Waterfall chart added|
|January 2015||Scatter plots added|
|Spring 2015||Policy Evaluation Model (PEM) goes GGIG, used in introductionary class on Agricultural Policy|
|December 2014||Support for dependencies between controls|
|December 2014||Support for different Look and Feel implementations|
|November 2014||Map viewer supports flexible regional aggregation|
|October 2014||New file selection control with separate box for sub-directories|
|October 2014||Support for SVN version 1.8|