COCOMO

COCOMO (Constructive Cost Model) is a software cost estimation model developed by Barry Boehm in the 1970s and refined over subsequent decades. It estimates the cost, effort, and schedule of software projects based on historical project data and parameters such as project size, complexity, team experience, and tool maturity. COCOMO was one of the first models to treat software development as a measurable economic process rather than an unpredictable creative endeavor, and it established the principle that software engineering decisions should be grounded in empirical data rather than intuition alone.

The model exists in three forms: basic COCOMO, which uses only source lines of code as input; intermediate COCOMO, which adds cost drivers for hardware, personnel, and project attributes; and detailed COCOMO, which estimates effort at the module level and integrates the estimates into a total project cost. Each successive version adds granularity at the cost of requiring more detailed project data.

COCOMO's predictive accuracy has been debated, but its deeper contribution is cognitive: it forced software practitioners to articulate and debate assumptions about productivity, scale, and risk that had previously been implicit. The model structured the conversation about software projects in terms of variables that could be measured, disputed, and improved.