Issues of organisational behaviour in effort estimation for development projects

A study of the way people made judgments when planning development projects showed that organisational behaviour can lead to bias in estimates of required effort. It supported previous, experimental findings that planners are reluctant to accept the uncertainty that is inherent in development activity. As a result they sometimes—although not always—adopted strategies that appeared to be inappropriate to the estimating task. They also tended to believe that there was no distinct expertise involved in effort estimation, they had questionable beliefs about how they could calibrate their judgments in the light of experience, and they misdiagnosed unusual events. The study found that these problems were sometimes exacerbated at the organisational level. Organisations fail, for instance, to maintain a clear distinction between goals and predictions, they do not keep the records needed to calibrate estimating judgments, and they seem to misattribute the causes of surprise. Some of the findings reflect basic psychological and organisational effects, and for a number of reasons the most promising remedy is better training of staff.