Orthogonal Defect Classification - ODC

What Orthogonal Defect Classification (ODC) brings to software engineering can be captured in two words: INSIGHT and SPEED.

One leads to the other. But, they are not the only things that cause our eyes to light up and the organization hum with excitement. It's the power we gain through practical knowlege to affect the right engineering and process change that makes the difference.

Fault versus Failure

Ram Chillarege, 2010

Fault and Failure are two terms that are often confused. In every day life they conjure up similar images of something going wrong. Even in technical circles the terms are used interchangeably further distorting the differences. However, in technical terms they are two very different things. I say "things", but, really, only one of them comes close to being a thing - the other being an "event" and less of a thing. Let us study these a little deeper since we need to be more exacting for the purposes of defect analysis and software engineering.

Test and Development Process Retrospective - a Case Study using ODC Triggers

Ram Chillarege and Kothanda Ram Prasad Chillarege Inc., 2002

Abstract --We present a case study of a product development retrospective analysis conducted to gain an understanding of the test and development process effectiveness. Orthogonal Defect Classification (ODC) is used as an analysis method to gain insight beyond what classical qualitative analysis would yield for the probable cause of delays during test.
   1. ODC Trigger analysis provides the insight to understand the degree of blockage in test, probable cause, and consequences to the test and development process.
   2.Trigger distribution changes with respect to time shows the stabilization of the product, and variation among components shows the systemic nature of issues.
   3. The study makes nine specific inferences and recommendations based on these analyses to guide the engineering of future releases

ODC - a 10x for Root Cause Analysis

Ram Chillarege
Chillarege Inc., 2006

SEE ALSO: 5 Differences between Classical and ODC Root Cause Analysis in Software


Abstract -- Orthogonal Defect Classification (ODC) allows us to do a "10x" on Root Cause Analysis (RCA). It is a 10x in terms of the time it takes to perform root cause analysis and a 10x in terms of the coverage on the defect stream. These productivity enhancements are achieved by raising the level of abstraction and systematizing the analysis methodology. The impact of this productivity boost is far-reaching in its business impact with reported gains that are enormous.

What Is Software Failure ?

Ram Chillarege, 1996

Commentary in IEEE Transactions on Reliability, Vol. 45, No.3, September 1996, while at  IBM Thomas J. Watson Research Center, Hawthorne, New York.

As software dominates most discussions in the information technology business, one needs to examine carefully where we are headed in software reliability. It is reasonable to ask about the nature of software faults and the remedy for them, either from a fault-tolerance perspective or, more generally, on a software depend­ability front. There are conferences on this topic, and over 300 technical papers that discuss some of its aspects.  However, as many industry specialists agree, software is one area in the information technology industry which continues to baffle the scientist from a dependability perspective. While hardware & technology have seen four orders of magnitude improvement in the past decade, software has probably marginally improved or, some will argue, gotten worse. One then wonders if research in this area is headed in the right directions?

Orthogonal Defect Classification - A Concept for In-Process Measurements

Orthogonal Defect Classification - A Concept for In-Process Measurements

Ram Chillarege, Inderpal S. Bhandari, Jarir K. Chaar, Michael J. Halliday, Diane S. Moebus, Bonnie K. Ray, Man-Yuen Wong, IBM Thomas J. Watson Research Center, 1992

Abstract -- This paper describes Orthogonal Defect Classification (ODC), a concept that enables in-process feedback to developers by extracting signatures on the development process from defects. The ideas are evolved from an earlier finding that demonstrates the use of semantic information from defects to extract cause-effect relationships in the development process. This finding is leveraged to develop a systematic framework for building measurement and analysis methods. This paper:
  • Defines ODC and discusses the necessary and sufficient conditions required to provide feedback to a developer.
  • Illustrates the use of the defect type distribution to measure the progress of a product through a process.
  • Illustrates the use of the defect trigger distribution to evaluate the effectiveness and eventually the completeness of verification processes such as inspection or testing.
  • Provides sample results from pilot projects using ODC.
  • Opens the doors to a wide variety of analysis techniques for providing effective and fast feedback based on the concepts of ODC.