STRENGTHENING THE VALIDITY OF SOFTWARE PROCESS IMPROVEMENT MEASUREMENTS THROUGH STATISTICAL ANALYSIS: A CASE STUDY AT ERICSSON AB

Abstract

Measuring Software Process Improvements is a challenge for software organizations. It is difficult to find a non-questionable way to show that improvement actually has taken place. Through process employee surveys it is possible to design questions and key ratios that help us understand current situations and trends. The telecom company Ericsson AB has been working with such measurements since early 2001. In this thesis we investigate the result of such a survey through basic statistical analysis. We conclude that the statistical analysis of the process employee survey investigated in this thesis shows strong consistency and validity of both survey questions and key ratios. We also conclude that we can strengthen the statistical validity in SPI measurements through the use of basic statistical analysis. In this study we suggest a set of practical steps that can be performed on SPI measurements in order to strengthen their validity. We also present an iterative process model that could be used at Ericsson to assure quality in their SPI measurements and improve future SPI measurements.