Calibration of the Checkpoint Model to the Space and Missile Systems Center (SMC) Software Database (SWDB)

This study analyzed the effect of calibration on the performance of the CHECKPOINT Version 2.3.1 software cost estimating model. Data used for input into the model were drawn from the FY 95 USAF SMC Software Database (SWDB) Version 2.1. A comparison was made between the model\u27s accuracy before and after calibration. This was done using records which were not used in calibration, referred to as validation points. A comparison of calibration points, both before and after, was done in order to assess whether calibration results in more consistency within the data set used. Six measures such as magnitude of relative error (MRE), mean magnitude of relative error (MMRE), root mean square error (RMS), relative root mean square error (RRMS), the prediction at level k/n, and the Wilcoxon Signed-Rank Test were used to describe accuracy. The results of this effort showed that calibration of the CHECKPOINT model can improve cost estimation accuracy for development effort by as much as 96.71%