Megaprojects : the quality of cost estimates and demand forecasts : a literature review. Actual costs of megaprojects are very often much higher than assumed when the decision to construct them was made. The difference is bigger for rail projects than for roads. Strategic behaviour of actors that benefit from the construction is an important explanation for this difference. The use of megaprojects is often lower than forecasted at the time of the decision making process, especially for rail projects. The quality of models and the model input is not the most important factor for differences between forecasts and actual use. Again strategic behaviour is an important factor. Literature gives several ideas to decrease the discrepancies between costs and demand forecasts and actual costs and demand. (Author/publisher)
Abstract