We ask various experts, who produce sales forecasts that can differ from earlier received modelbased forecasts, what they do and why they do so. A questionnaire with a range of questions was completed by no less than forty-two such experts who are located in twenty different countries. We correlate the answers to these questions with actual behavior of the experts. Our main findings are that experts have a tendency to double count and to react strongly to recent volatility in sales data. Also, experts who feel more confident give forecasts that differ most from model-based forecasts.
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