This Article 
 Bibliographic References 
 Add to: 
An Experiment Measuring the Effects of Personal Software Process (PSP) Training
May 2001 (vol. 27 no. 5)
pp. 465-472

Abstract—The Personal Software Process is a process improvement methodology aimed at individual software engineers. It claims to improve software quality (in particular defect content), effort estimation capability, and process adaptation and improvement capabilities. We have tested some of these claims in an experiment comparing the performance of participants who had just previously received a PSP course to a different group of participants who had received other technical training instead. Each participant of both groups performed the same task. We found the following positive effects: The PSP group estimated their productivity (though not their effort) more accurately, made fewer trivial mistakes, and their programs performed more careful error-checking; further, the performance variability was smaller in the PSP group in various respects. However, the improvements are smaller than the PSP proponents usually assume, possibly due to the low actual usage of PSP techniques in the PSP group. We conjecture that PSP training alone does not automatically realize the PSP's potential benefits (as seen in some industrial PSP success stories) when programmers are left alone with motivating themselves to actually use the PSP techniques.

[1] L.B. Christensen, Experimental Methodology. sixth ed., Needham Heights, Mass.: Allyn and Bacon, 1994.
[2] B. Efron and R. Tibshirani, “An Introduction to the Bootstrap,” Monographs on Statistics and Applied Probability 57, 1993.
[3] P. Ferguson et al., "Results of Applying the Personal Software Process," Computer, Vol. 30 No. 5, May 1997, pp. 24-31.
[4] W. Hayes and J.W. Over, “The Personal Software Process (PSP): An Empirical Study of the Impact of PSP on Individual Engineers,” Technical Report CMU/SEI-97-TR-001, Software Eng. Inst., Carnegie Mellon Univ., Pittsburgh, Penn., 1997.
[5] W.S. Humphrey, Managing the Software Process, Addison-Wesley, Reading, Mass., 1989.
[6] W.S. Humphrey, A Discipline for Software Engineering, Addison-Wesley, Reading, Mass., 1995.
[7] W.S. Humphrey, "Using a Defined and Measured Personal Software Process," IEEE Software, Vol. 13 No. 3, May 1996, pp. 77-88.
[8] P.M. Johnson and A.M. Disney,"The Personal Software Process: A Cautionary Case Study," IEEE Software, vol. 15, no. 6, Nov./Dec. 1998, pp. 85-88.
[9] H.M. Parsons, “What Happened at Hawthorne?” Science, vol. 183, no. 8, pp. 922–932, Mar. 1974.
[10] L. Prechelt and G. Grutter, “Accelerating Learning from Experience: Avoiding Defects Faster,” IEEE Software, submitted for 2000.
[11] L. Prechelt and B. Unger, “A Controlled Experiment on the Effects of PSP Training: Detailed Description and Evaluation,” Technical Report 1/1999, Fakultät für Informatik, Univ. Karlsruhe, Germany, Mar. 1999,
[12] L. Prechelt and B. Unger, “How Does Individual Variability Influence Schedule Risk?: A Small Simulation with Experiment Data,” Technical Report 1999-12, Fakultät für Informatik, Univ. Karlsruhe, Germany, Sept. 1999,

Index Terms:
Process improvement, quality management, effort estimation, reliability, productivity, experiment.
Lutz Prechelt, Barbara Unger, "An Experiment Measuring the Effects of Personal Software Process (PSP) Training," IEEE Transactions on Software Engineering, vol. 27, no. 5, pp. 465-472, May 2001, doi:10.1109/32.922716
Usage of this product signifies your acceptance of the Terms of Use.