(Last modified Thu Jun 05 23:07 2008)
This table brings together several different kinds of data from a number of sources.
| Phase | Percent of defects introduced | QA activities | Defect identification efficiency | Relative cost of removing one defect |
|---|---|---|---|---|
| Requirements | 15% | Requirements review | 50% | 1 |
| Design | 35% | Design inspection (by peers) | 60% | 2.5 |
| Design review (by experts) | 50% | |||
| Coding | 30% | Code inspections (by peers) | 65% | 6.5 |
| Unit test | 30-50% | |||
| Integration | 10% | Integration test | 50% | 16 |
| System and acceptance tests | 50% | 40 | ||
| Documentation | 10% | Documentation review | 10% | |
| After release | (No data) | Software maintenance | (100%) | 110 |
| Phase/activity | Introduced | Efficiency | Removed | Cost | Remaining |
|---|---|---|---|---|---|
| Requirements | 15 | 15.00 | |||
| Requirements review | 50% | 7.5 | 7.5 | 7.5 | |
| Design | 35 | 42.5 | |||
| Design review | 50% | 21.3 | 53.1 | 21.3 | |
| Coding | 30 | 51.3 | |||
| Unit test (without code inspection) | 50% | 25.6 | 166.6 | 25.6 | |
| Integration | 10 | 35.6 | |||
| Integration tests | 50% | 17.8 | 285.0 | 17.8 | |
| Documentation | 10 | 27.8 | |||
| Documentation review | 50% | 13.9 | 556.3 | 13.9 | |
| System acceptance test | 50% | 7.0 | 278.1 | 7.0 | |
| Maintenance | 100% | 7.0 | 764.8 | 0.0 | |
| Total | 100 | 100% | 100 | 2111 |
For purposes of this calculation, we count only the defects we find; we know there are more but not how many.
| Phase/activity | Introduced | Efficiency | Removed | Cost | Remaining |
|---|---|---|---|---|---|
| Requirements | 15 | 15.0 | |||
| Requirements review | 50% | 7.5 | 7.5 | 7.5 | |
| Design | 35 | 42.5 | |||
| Design inspection (by designer's peers) | 60% | 25.5 | 63.8 | 17.0 | |
| Design review (by senior people) | 50% | 8.5 | 21.3 | 8.5 | |
| Coding | 30 | 38.5 | |||
| Code inspection (by coder's peers) | 65% | 25.0 | 162.7 | 13.5 | |
| Unit test (following code inspection) | 30% | 4.0 | 26.3 | 9.4 | |
| Integration | 10 | 19.4 | |||
| Integration tests | 50% | 9.7 | 155.5 | 9.7 | |
| Documentation | 10 | 19.7 | |||
| Documentation review | 50% | 9.9 | 394.3 | 9.9 | |
| System acceptance test | 50% | 5.0 | 197.2 | 4.9 | |
| Maintenance | 100% | 5.0 | 542.2 | 0.0 | |
| Total | 100 | 100% | 100 | 1571 |
Galin's comprehensive plan calculations assume all QA activities are more efficient than under the standard plan. If the higher efficiencies can be achieved, the results are even better.
| Phase/activity | Introduced | Efficiency | Removed | Cost | Remaining |
|---|---|---|---|---|---|
| Requirements | 15 | 15.0 | |||
| Requirements review | 60% | 9.0 | 9.0 | 6.0 | |
| Design | 35 | 41.0 | |||
| Design inspection (by designer's peers) | 70% | 28.7 | 71.8 | 12.3 | |
| Design review (by senior people) | 60% | 7.4 | 18.5 | 4.9 | |
| Coding | 30 | 38.5 | |||
| Code inspection (by coder's peers) | 70% | 24.4 | 158.9 | 10.5 | |
| Unit test (following code inspection) | 40% | 4.3 | 27.2 | 6.3 | |
| Integration | 10 | 19.4 | |||
| Integration tests | 60% | 9.8 | 156.3 | 6.5 | |
| Documentation | 10 | 19.7 | |||
| Documentation review | 60% | 9.9 | 396.3 | 6.6 | |
| System acceptance test | 60% | 4.0 | 158.5 | 2.6 | |
| Maintenance | 100% | 2.6 | 290.7 | 0.0 | |
| Total | 100 | 100% | 100 | 1287 |
