Team Software Process (TSP) - TSP Quality Management

Team Software Process (TSP) shows teams how to manage quality, teams must establish quality measures, set quality goals, establish plans to meet these goals, measure progress against the plans, and take remedial action when the goals are not met.

ELEMENTS OF TSP QUALITY MANAGEMENT

- Preparing a quality plan.
- Identifying quality problems.
- Finding and preventing quality problems.

PREPARING A QUALITY PLAN
TSP make a quality plan based on the estimated size of the product and historical data on defect injection rates, they estimate how many defects they will inject in each phase. Once the engineers have estimated the defects to be injected, they estimate defect removal,again using historical data or the TSP quality guidelines which are based on the yield for each defect removal phase. Once the injection and
removal estimates have been made, the team can generate the quality plan.

IDENTIFYING QUALITY PROBLEMS
TSP provides many quality measures one of them being is by comparing the data for any module or component with the quality plan. TSP introduces a series of quality measures like: Process quality index—PQI.
- Percent defect free—PDF: Comparing the PDF curves for several similar projects. Where there are problems, the quality manager can look at data on lower level components to identify the source of the problem and recommend what the team should do about it. PDF plot can only be produced for an overall system or large component.
- Defect-removal profile: The defect-removal profile can be drawn for the system, each of its subsystems, any component, or even down to the module level.
- Quality Profile: The quality profile measures the process data for a module against the organization’s quality standards. The five quality profile dimensions indicate module quality based on data for design, design reviews, code reviews, compile defects, and unit test defects.
- Process quality index—PQI: is produced by taking the product of the five dimensional values of the quality profile to produce a single quality figure of merit. With PQI values above about 0.4, program modules are generally defect free.

FINDING AND PREVENTING QUALITY PROBLEMS
The TSP quality measures can indicate likely quality problems even before the first compile. Once the problems are identified, they can be prevented by:
- Monitor the module during test to see if problems are found and then determine the remedial action.
- Reinspect the module before integration or system test.
- Rework on the module to fix suspected problems.
- Redevelop the module.