An empirical study of ICASE learning curves and probability bounds for software development effort

In this paper, we investigate the existence of learning curves in software development. Under the assumption of independent and identical distribution (iid) of programmer's experience and identical effort-experience learning curve relationship for different programmers, we illustrate the existence of an exponentially decreasing learning curve relationship between a programmer's effort and his/her ICASE tool experience, and show that the effort-experience relationship is inelastic when a programmer's ICASE tool experience is low. We analyze the impact of our assumptions on actual software development effort, and propose a tight probability upper bound and a central-limit theorem based probability estimator for estimating the approximate probability that the software development effort will be less than or equal to a certain number. Examples to illustrate the use of the probability estimator are also provided.