A New Graphical User Interface Generator for Economic Models and its Comparison to Existing Approaches Ein neues Werkzeug zur Erstellung Graphischer Oberflächen für ökonomische Modelle und sein Vergleich zu bestehenden Ansätzen

The paper discusses the role of Graphical User Interfaces in economic modelling and specifically the development of a new Graphical User Interface Generator for applications realized in GAMS (General Algebraic Modelling System), a widely used Algebraic Modelling Language for (bio-)economic simulation models. It motivates the development of GGIG (Gams Graphical Interface Generator) by reviewing existing approaches. In opposite to frameworks available for environmental and Agent Based Modelling, GUI generators for more classical economic models seem to be scarce. GGIG aims at a fast development process not requiring programming skills where simple user operable controls are defined in an XML file such that GAMS based projects can add easily a GUI. It comprises quite versatile exploitation tools for interactive reporting (tables, graphs and maps) including a machine learning package plus useful utilities, e.g. to generate a HTML based GAMS code documentation or batch execution. In opposite to other approaches, GGIG strictly separates the GUI and GAMS code, but does not offer IDE functionality. Applications to CAPRI, a rather complex model, and some smaller projects seem to show that researchers without formal programming training are able to develop and modify a GUI for their models, while model users can be quickly trained in GGIG based GUIs.