A Comparative Study of the Reliability of Function Point Analysis in Software Development Effort Estimation Models

The Air Force of the 1990s is steadily growing more reliant on software systems. However, the struggle to develop reliable cost and effort estimation tools continues. The Standard Systems Center SSC, Gunter AFB AL, has adopted the use of Function Point Analysis to improve estimation of data processing, management and communication systems. Function point analysis was introduced by IBMs Alan Albrecht in 1979 as an alternative to source line of code SLOC as a size and productivity measure. In 1991, Tecelote Research, Inc. , under contract to the SSC, delivered the Software Program Acquisition Network Simulation SPANS model incorporating the capability to perform estimates using function point measures. This research examines the ability of SPANS to reliably and accurately estimate software project effort with function points. A further investigation compares the predictions derived by SPANS with two other software estimation tools, Checkpoint and Costar.