Cost estimation for web applications

In this paper, we investigate the application of the COBRA™ method (Cost Estimation, Benchmarking, and Risk Assessment) in a new application domain, the area of web development. COBRA combines expert knowledge with data on a small number of projects to develop cost estimation models, which can also be used for risk analysis and benchmarking purposes. We modified and applied the method to the web applications of a small Australian company, specializing in web development. In this paper we present the modifications made to the COBRA method and results of applying the method In our study, using data on twelve web applications, the estimates derived from our Web-COBRA model showed a Mean Magnitude of Relative Error (MMRE) of 0.17. This result significantly outperformed expert estimates from Allette Systems (MMRE 0.37). A result comparable to Web-COBRA was obtained when applying ordinary least squares regression with size in terms of Web Objects as an independent variable (MMRE 0.23).