The aim of this study is to identify an optimism bias in macroeconomic predictions and to suggest hypothesis which could explain it. I divide optimism to "static optimism" (constantly overvalued prediction by certain constant value) and the "dynamic optimism" (the longer period is being predicted, the higher over-optimism would appear). Although the first phenomenon was not proved, the dynamic optimism has been confirmed on dataset of real GDP growth forecasts from 10 different forecasting insti... zobrazit celý abstraktThe aim of this study is to identify an optimism bias in macroeconomic predictions and to suggest hypothesis which could explain it. I divide optimism to "static optimism" (constantly overvalued prediction by certain constant value) and the "dynamic optimism" (the longer period is being predicted, the higher over-optimism would appear). Although the first phenomenon was not proved, the dynamic optimism has been confirmed on dataset of real GDP growth forecasts from 10 different forecasting institutions. Possible political influence on predictions from ministries was tested, but was not confirmed. On the basis of interviews with analysts, possible explanations of over-optimism phenomenon are discussed in final part of the paper. |