Amending schedule-cost coefficient correlation based on historical statistics

The schedule-cost correlation coefficient is usually estimated by experts in the spaceflight project management practice. This paper deduced the schedule distribution model considering the effect of the cost uncertainty. And then theoretically analyzed and demonstrated how to amend the schedule-cost correlation coefficient according to the historical statistics based on the conditional probability distribution functions between the schedule and the cost. A general rule was put forward to ascertain the value of the schedule-cost correlation coefficient. This method was proved in analytical method. This work can correct the traditional subjective estimation method just according to the experts´ experiences and expertise.