This report discusses the methodology used for the appraisal of investment in transport infrastructure in Austria. The approach, used for transport infrastructure investment as a practical task, views transport infrastructure construction and maintenance as a collective task extending across the generations, and as matters of concern to the economy. The following methodological issues, arising in transport infrastructure investment, are discussed: (1) the systems approach as an aid to decision; (2) the methodological cycle 'real problem - formal problem - formal solution - real problem'; (3) the investment calculation as a decision rule; (4) the dilemma of dynamic investment calculation; (5) the controversial question of interest payments on capital tied up in transport infrastructures; (6) whether the decision calculation should only provide information about the costs and benefits of the relevant project variants, or whether it should also assess the chances of implementation. It should not be forgotten that many advantages have resulted from computerisation of the task of evaluation and choice of investment in transport infrastructures. Not only can single point results be produced, but their stability can be checked; sensitivity analysis plays an important part here. It is also possible to test many calculation variants in a very short time.
Samenvatting