Compilation Data for Projects Using TSP and PSP
The following charts are a compilation of results data from projects at Teradyne, Boeing, AIS and Hill Air Force Base. Data from 18 TSP/PSP projects in these organizations were combined to illustrate before and after performance ranges for
- post-release defects/KLOC
- system test duration
- defects/KLOC in acceptance test
- schedule deviation
- effort deviation
The ranges are the minimums and maximums from this data.
The sharp decrease in the number of defects found in software that was developed using TSP and PSP could be attributed to the emphasis on quality throughout the development process. Because TSP teams systematically search for defects from the beginning of the development process, customers rarely find defects in the final product.
Software developed by TSP teams passes through system and acceptance test relatively quickly, again because of the emphasis on quality from the beginning of the software process. Most defects are found early in the development cycle when they can be fixed at a much lower cost.
TSP teams are able to estimate their schedule and effort very accurately because of the reduced dependence on the less predictable test phases of the development cycle and because PSP-trained engineers are precisely aware of how long development tasks have taken them to complete in previous efforts.
For More Information
For more information about TSP, contact tsp@sei.cmu.edu.