Software Development Cost Estimation for Infrastructure Systems

Abstract

Modern infrastructure systems, ranging from transportation to water and sewer systems, are becoming increasingly dependent on software. The role it plays in these systems is primarily to integrate and manage elements that support system operations. In other words, software has transformed what were previously considered to be largely static systems to active, dynamic systems. In general, infrastructure system software is characterized by an emphasis on the following core functions: (1) sensor management; (2) data analysis; (3) data management; and (4) equipment control interfaces. As the nature of infrastructure systems changes, the tools available to support their design and management must change as well. The construction engineering community has developed sound techniques and resources to support the estimation of costs for physical construction of infrastructure systems. However, such tools are not readily available to support the cost estimation of the software component of infrastructure system development and construction. In this research effort, a widely used software engineering cost-estimation technique, the construction cost model (COCOMO), was examined to determine if it is effective for infrastructure system application. This examination included a sample application of COCOMO to an infrastructure system software project and a critical analysis of the technique itself. The examination revealed that COCOMO is extremely sensitive to small variations in an estimator’s judgment, and that the foundation of the COCOMO model is poorly suited for infrastructure system application. As a result, it is recommended that a research and development program be initiated to create specific tools to support the cost estimation of infrastructure system software development.