Competence and confidence effects in experts' forecast adjustments

It frequently occurs that experts adjust forecasts from statistical models. There is some evidence that such adjusted forecasts can lead to substantially better performance. Little is known about competence and confidence effects in what these experts do. Theoretical and experimental results in the decision-making literature suggest that those effects should well exist for experts' adjustment. We examine this possibility for a unique data set concerning managers in thirty-seven countries who adjust statistical model-based forecasts delivered by the headquarters of a large pharmaceutical firm. Our literature-consistent findings are that older and younger managers adjust more than middle-aged managers and that a female manager adjusts less, except in the case where she has more experience.