| Popis: |
Judgmentally adjusting a statistical forecast before using it is a widespread practice in business. The goal of this study is to provide a deeper understanding of judgmental adjustments of statistical forecasts to improve forecasting performance. The forecasting performance is measured with three dependent variables. The first dependent variable is accuracy improvement which represents the positive change in forecast accuracy after a judgmental adjustment. The second dependent variable is learning which refers to the continuous improvement of a forecaster’s performance over time. The third variable is actually a set of variables that includes various biases. A bias is a systematic deviation in forecasts that is introduced by a particular forecaster. The independent variables included in this study are personality variables, motivational variables and situational variables. Personality is measured by the Big-Five model that analyzes an individual’s personality in five dimensions including extraversion, conscientiousness, neuroticism, agreeableness and openness to experience. Motivational variables are measured in terms of motivational orientation and various motivational stimuli. Situational variables include feedback, supervision, timing of adjustment, and demographics. Data were collected from a company where store managers used judgmental adjustments of statistical forecasts to improve the forecast accuracy for their stores. The data collection covered a period of 12 months and 390 stores over several Midwestern and southeastern states. The data for dependent variables were obtained from forecasting records and the data for independent variables were collected using a survey instrument. The results indicate that, on average, judgmental adjustments of statistical forecasts result in accuracy improvement. The extent of the accuracy improvement is affected by personality, motivational and situational variables. Furthermore, there was evidence for biases that were introduced through judgmental adjustments. Biases were also moderated by personality, motivational and situational variables. This study detected no evidence of learning. |
