Over prijsraming en prijsvorming op de bouwmarkt

The analysis deals with the ratio of actual to predicted prices of building projects for a big city in the Netherlands in the period 1946–1953. These forecasts had been made by the city's civil servants as a guide to building policy. It appears that the ratio of actual to predicted prices was of the order of 0.85 on the average, which implies a tendency to overestimate the actual prices to be paid. This ratio has an average which is closer to 1 for large projects than for small ones, and the standard deviation around the mean is smaller for large projects. Further more it appears that this standard deviation decreased systematically in the course of time.