Dlaczego wydajemy więcej, niż zamierzaliśmy? Błąd preliminarza
Rocznik: 2010 Tom: 16 Numer: 2
The budget fallacyconcept is introduced by analogy to the planning fallacyconcept. The budget fallacyconsists in the underestimation of the costs of a future financial venture: the planned costs are lower than the actual costs. Three studies were conducted to see whether the preliminary estimate fallacy is only limited to institutional budget planning or is also typical for personal, everyday budgets. It was hypothesized that people tend to underestimate future expenses. The experimental design was analogous to the designs adopted in the research on planning fallacy and involved two steps: (1) Respondents were asked how much money they planned to spend on particular ventures and then (2) actual expenditure was calculated. In study one (N=39) respondents were requested to make a preliminary shopping estimate. In study two (N=80) they were asked to prepare a weekly household budget. In study three (N=90) they were asked to predict holiday expenses. In all cases respondents underestimated actual costs. In his discussion of the preliminary estimate fallacy, the author refers to motivational and cognitive factors and especially to what he calls the underestimation heuristic.