1. Tom Gilchrist, tomg@tomgtomg.com The "Two Engine Model" for Software Quality Measurement and Improvement A lively romp through process capability, documentation, and measurement without getting your feet wet. By Tom Gilchrist SASQAG, Aug 2011

2. Tom Gilchrist, tomg@tomgtomg.com Disclaimer  The views and opinions in this presentation are my own and do not necessarily reflect those of my employer….  Context is everything…your mileage may vary.  If you don’t try something different, don’t be surprised that the outcome doesn’t change!

3. Communication with an engineering is only a little more difficult than communication with the dead.

4. Tom Gilchrist, tomg@tomgtomg.com Tonight...  Some Context  Feedback Systems  Change or Improvement?

5. Tom Gilchrist, tomg@tomgtomg.com Some Definitions….  Process:  Process: How we remember things that work, so we can repeat them. How we remember things that don’t work, so we can avoid them.  Errors, Defects, Faults, and Failures Error: Error: a human action or mistake that results in the SW containing a defect. (MEWU) Defect:Fault Defect: a Fault that exists in the software, which if not corrected, could cause the software to fail or produce incorrect results Failure: Failure: An occurrence of the SW not meeting its requirements or intended usage while it is being executed.

6. Tom Gilchrist, tomg@tomgtomg.com Coding Acceptance Production Change BoardSubs Post-Release Failures Development Errors/Defects Pre-Development Errors Dev Tests Int Tests RequirementsCOTS Pre-Release Failures Quality Measurement Areas Design

7. Tom Gilchrist, tomg@tomgtomg.com Coding Acceptance Production Change BoardSubs Post-Release Failures Development Errors/Defects Pre-Development Errors Dev Tests Int Tests RequirementsCOTS Pre-Release Failures Quality Measurement Areas Design Escape Rates, Efficiency & Effectiveness

8. Tom Gilchrist, tomg@tomgtomg.com Understanding Rework WORK TO BE DONE WORK REALLY DONE UNKNOWN REWORK Work Being Done People Productivity Quality Rework Discovery KNOWN REWORK *From IEEE Engineering Management Review, Winter 1994 Why is rework bad?

9. Tom Gilchrist, tomg@tomgtomg.com Single Engine Model Needs & Constraints Deliverables Exit Criteria ACTION Internal Business Objectives & Constraints CONTROL Usage Results MEASUREMENT Entry Criteria Trigger PROCESS CYCLE

10. Tom Gilchrist, tomg@tomgtomg.com Two Engine ModelResults Maintain and Improve the Process Use the Process Organization Projects LessonsLearned Professional Practices