Tagged research
3 pieces
- · 5 min read
Does Test Discipline Actually Reduce Bugs? The Honest Numbers
Four industrial teams saw pre release defect density fall between 40 and 90 percent, at a subjective cost of 15 to 35 percent more initial development time. A controlled study of 24 professionals found an 18 percent higher pass rate at 16 percent more time. Directionally strong, causally soft, and not free.
- · 6 min read
Do Injected Faults Track Real Bugs? The Case for Mutation Testing
Across 357 real faults and 230,000 mutants, a coupling relationship held for 73 percent of real faults, and mutant detection tracked real fault detection more strongly than statement coverage did. The honest limit is that 17 percent of real faults couple to no mutant even in principle.
- · 7 min read
High Coverage Does Not Mean Safe Code: What the Research Actually Says
Control for suite size and the correlation between coverage and fault detection drops to low or moderate. Against real post release defects it is statistically insignificant. Two credible studies push back, and the disagreement is mostly about method. The claim that survives all of it is that coverage is a floor, not a target.