What is Estimated Software Size

This chapter describes a case study where Bayesian Networks (BNs) were used to construct an expert-based software effort and risk prediction model for use by a large healthcare organisation in Auckland (New Zealand) to manage healthcare software projects delivered on the Web. This model was solely elicited from expert knowledge, with the participation of seven project managers, and was validated using data from 22 past finished projects. The model led to numerous changes in process and also in business. The company adapted their existing effort and risk management process to be in line with the model that was created, and the use of a mathematically based model also led to an increase in the number of projects being outsourced to this company by other company branches worldwide. Their predictions improved significantly too. The results suggest that the use of a model that allows the representation of uncertainty, inherent in effort estimation, can outperform expert-based estimates.