Influence of behavioral factors on project schedule management: A Monte Carlo method

Abstract

The PERT/CPM method adopts the right-skewed probability distribution of activity duration to describe human behavioral characteristics in project activity. The parameters of distribution are given directly by estimators, which means a fixed distribution is used. However, due to the influence of "student syndrome" and Parkinson's Law, the PERT/CPM method doesn't get a satisfying effect. The CCPM method recently studied takes account of these factors by taking advantage of the mechanism of buffers and achieves better results, nevertheless, its theoretical foundations have not been confirmed effectively. This paper employs a dynamic probability distribution of activity duration to describe the influence of "student syndrome" and Parkinson's Law on the project, and uses Monte Carlo simulation method to investigate the influence of on the completion rate for the planned project duration. We find "student syndrome" and Parkinson's Law can change the expectation of project completion time and as the degree of waiting and procrastination increases, the completion rate continues to decrease. Meanwhile, the principle of cutting down safety time in CCPM is also interpreted. In the end, the paper presents some managerial policies to guide the project participants' behavior and improve the project operation efficiency.