KC 8.2.3 – Product Measurements - Defect Metrics

Defects Per Unit (DPU)

A "Unit" simply refers to the bounded work-product that is delivered to a customer. In a software product, Units usually exist in a hierarchy - just as the software in a 'unit test' (a Unit at that level) may be integrated into subsystems (each one a Unit at the next higher level) and finally a system (a high level Unit).

DPU, the simplest Six Sigma measure, is calculated as Total Defects/Total Units. If 100 units are inspected and 100 defects are found, then DPU = 100/100 = 1.

Defects (%)

Once you have determined the operational definition of what constitues a defect:

The total number of defects counted on the population in question divided by the total population count.

Defect Containment Effectiveness (DCE)

Go through this article to find out what exactly DCE is:

http://www.isixsigma.com/library/content/c031001a.asp

Defects per million opportunities (DPMO)

Defects per million opportunities (DPMO) is the average number of defects per unit observed during an average production run divided by the number of opportunities to make a defect on the product under study during that run normalized to one million.

Defects Per Million Opportunities. Synonymous with PPM.

To convert DPU to DPMO, the calculation step is actually DPU/(opportunities/unit) * 1,000,000.

Defects / Function Point or Defects per KLOC

No. of defects/Size in FPs or KLOC