Software Test Metrics

Software Test Metrics is used in decision making. The test metrics is derived from raw test data.
Because what cannot be measured cannot be managed. Hence Test Metrics is used in test management. It helps in showcasing the progress of testing.

Some of the Software Test Metrics are as below,

What is Test Summary

It is a document summarizing testing activities and results, and it contains an evaluation of the test items.

Requirements Volatility

Formula = {(No. of requirements added + No. of requirements deleted + No. of requirements modified) / No. of initial approved requirements} * 100
Unit Of measure = Percentage

Review Efficiency

Components - No. of Critical, Major & Minor review defects
- Effort spent on review in hours
- Weightage Factors for defects:
- Critical = 1; Major = 0.4; Minor = 0.1
Formula = (No. of weighted review defects/ Effort spent on reviews)
Unit Of measure = Defects per person hour

Productivity in Test Execution

Formula = (No. of test cases executed / Time spent in test execution)
Unit Of measure = Test Cases per person per day

Here the time is the cumilative time of all the resources. example - If there were 1000 Test cases executed in a cycle by 4 resources.
If resource 1 executed 300 test cases in 2 days,
resource 2 executed 400 test cases in 3 days
resource 3 executed 75 test cases in 1 day
resource 4 executed 225 test cases in 4 days.
Then the cumulative time spent for executing 1000 test cases is 10 man days.
Then the Productivity in Test Execution = 1000/10=100
So the productivity in test execution is 100 test cases per person per day.

Defect Rejection Ratio

Formula = (No. of defects rejected / Total no. of defects raised) * 100
Unit of Measure = Percentage

Defect Fix Rejection Ratio

Formula = (No. of defect fixes rejected / No. of defects fixed) * 100
Unit of Measure = Percentage

Delivered Defect Density

Components - No. of Critical, Major & Minor review defects
- Weightage Factors for defects:
- Critical = 1; Major = 0.4; Minor = 0.1
Formula = [(No of weighted defects found during Validation/customer review + acceptance testing)/ (Size of the work product)]
Unit Of measure = Defects for the work product / Cycle.

Outstanding defect ratio

Formula = (Total number of open defects/Total number of defects found) * 100
Unit Of measure = Percentage

COQ (Cost of Quality)

Formula = [(Appraisal Effort + Prevention Effort + Failure Effort) / Total Project effort] * 100
Unit Of measure = Percentage

Please refer to the below picture for the testing cost curve,

Some metrics related to the entire Test cycle.

Schedule Variance

Schedule variance wrt Latest Baselines
Formula = {(Actual End Date - Latest Baselined End Date)/(Latest Baselined End Date - Latest Baselined Start Date)} *100
Unit Of measure = Percentage

Schedule variance wrt Original Baselines
Formula = {(Actual End Date - Original Baselined End Date)/(Original Baselined End Date - Original Baselined Start Date)} *100
Unit Of measure = Percentage

Effort variance

Effort variance wrt Original Baseline
Formula = {(Actual Effort - Estimated Effort) / (Estimated Effort)}* 100
Unit Of measure = Percentage

Effort variance wrt Last Revised Baseline
Formula = {(Actual Effort - Revised Effort) / (Revised Effort)} * 100
Unit Of measure = Percentage