Software Complexity and Maintenance Costs

The effects of software complexity on the costs of Cobol maintenance projects within a large commercial bank are examined, and the impact of software complexity on the costs of software maintenance projects in a traditional information-system (IS) environment is estimated using a previously developed economic model of software maintenance. The model uses a multidimensional approach to measuring software complexity; other project factors that can be controlled by managers and that are believed to affect maintenance project costs are controlled for by the model. It is shown that software maintenance costs are affected significantly by software complexity in terms of module size, procedure size, and branching complexity. Dollar estimates are provided of the magnitude of the impact of software complexity on maintenance costs at a typical commercial site; the costs are high enough to justify complexity control and monitoring.Center for Information Systems ResearchCenter for the Management of Technology and Information in OrganizationsNational Science FoundationCenter for the Management of Technology and Information in OrganizationsInternational Financial Services Research CenterNational Science Foundation Grant No. SES-870904