MODELING ON THE BASIS OF MODELS

A large part of official economic data sets is produced with the help of assumed functional relations between variables. Constructing economic models on the basis of such model-generated data results in a "modeling on the basis of the results of modeling." This common procedure can lead to consequences that seriously endanger the quality of empirical analyses. After discussing some of these dangerous consequences the authors explore the reasons behind this development. To avoid some of the most severe difficulties a "Charter for Compilation and Correct Handling of Economic Data" is proposed.     

A general qualitative technique for the comparison of economic structures

Quantitative methods normally do not fully exhaust nor sufficiently show the structural information contained in sets of data. Therefore the authors introduce a new general technique for analyzing structures which is based on qualitative methods. The proposed technique can be divided into several steps. First, the given structural information is prepared with the help of graph theoretical tools. Then the obtained results are condensed in several steps to manageable vectors (key values), the most important step being the construction of graph theoretical decay patterns. These strongly condensed data allow the use of statistical methods and offer the chance to compare even a large number of structures simultaneously. After having introduced the necessary theoretical tools, the authors then present the results of some empirical investigations which showed the usefulness of the proposed technique. Compared with the corresponding quantitative methods, the empirical investigations also showed that our technique is relatively robust with respect to short-comings in the primary material. This result opens up opportunities for obtaining more actual yet costsaving structural information.