Pareto (80-20) Analysis

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A test focusing strategy. Analyze the defect patterns and identify their causes and sources or likely sources, and rank them by frequency of occurrence and criticality based on the 80-20 rule. Add test cases to check if the most likely or risky causes result in defects. Focuses the testing on those locations or parts of the system where the prior incidence and cost of defects have been highest. ("Hunt for the bugs where the critters hang out.")

See also Pareto Principle.

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