Interval Quality: Relating Customer-Perceived Quality to Process Quality

The authors investigate relationships among software quality measures commonly used to assess the value of a technology, and several aspects of customer perceived quality measured by Interval Quality (IQ): a novel measure of the probability that a customer will observe a failure within a certain interval after software release. They integrate information from development and customer support systems to compare defect density measures and IQ for six releases of a major telecommunications system. The authors find a surprising negative relationship between the traditional defect density and IQ.