Cost of Quality

Cost of Quality: Definition, Explanation, Formula, Calculation, Notes: DEFINITION Cost of Quality (COQ) is a measure that quantifies the cost of control/conformance and the cost of failure of control/non-conformance. In other words, it sums up the costs related to prevention and detection of defects and the costs due to occurrences of defects. Definition by ISTQB: […]

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Defect Detection Efficiency

DEFECT DETECTION EFFICIENCY Fundamentals DEFINITION Defect Detection Efficiency (DDE) is the number of defects detected during a phase/stage that are injected during that same phase divided by the total number of defects injected during that phase. ELABORATION defects: Are confirmed and agreed upon (not just reported). Dropped defects are not counted. phase: Can be any […]

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Defect Density

Defect Density Fundamentals DEFINITION Defect Density is the number of confirmed defects detected in software/component during a defined period of development/operation divided by the size of the software/component. ELABORATION The ‘defects’ are: confirmed and agreed upon (not just reported). Dropped defects are not counted. The period might be for one of the following: for a […]

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Defect Age

Defect Age Definition, Elaboration, Formula, and Uses: Defect Age can be measured in terms of any of the following: Time Phases DEFECT AGE (IN TIME) Definition Defect Age (in Time) is the difference in time between the date a defect is detected and the current date (if the defect is still open) or the date […]

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