Software Test Metrics

We come across different kinds of software testing metrics during testing which are very helpful during test strategy and test planning .

Below are few software testing metrics.

1) Test coverage metrics :

(No of requirements covered for test case development) / (Total no of requirements)

2) Test case design productivity :

(No of test cases developed) / (Engineering day)

Here 1 engineering day is 8 hours.

Standard value for test case design productivity is 25 to 30.

3) Test case execution productivity :

(No of test cases executed) / (Engineering day)

Standard value for test case execution productivity is 30 to 35.

Test effort estimation

1) Schedule variance = ((Estimated Schedule – Actual Schedule)/Estimated Schedule)) * 100

2) Effort variance = ((Estimated effort – Actual effort)/Estimated effort)) * 100

Defect metrics

1) Defect prevention ratio :

((Sum of all review defects) + (Number of unit test defects) ) / ((Numerator) + (Sum of defects in integration and system testing))

Acceptable value for defect prevention ratio is 0.85

2) Defect detection ratio :

((Sum of all review defects) + (Sum of integration testing and system testing defects)) / ((Numerator) + (Sum of user acceptance testing defects))

Acceptable value for defect detection ratio is 0.98.

Any suggestions for improvements is appreciated.

Best Regards

Narasimha Murthy.

Test Strategy and Test Planning

Test strategy and Test planning coexists in testing world.

Test strategy is done during design phase of a project. You already have a requirement, on which you can base your test strategy.
Test plan is done during the construction phase. You have requirements, strategy and design as inputs to your test plan.
The prototype of screen layouts are used to develop a major percentage of test cases during construction. When construction is done, the test cases are modified to suit the actual application after complete development.

Test Strategy

What are the contents of a test strategy document?

The test strategy document contains test cases, test conditions, test environment, a list of related tasks, pass/fail criteria and risk assessment.
The test strategy document is a formal description of how a software product or application will undergo the test.

What is the strategy document developed for?

It is developed for all levels of testing as required.

How a test strategy is written and who writes it?

Test team that analyses the requirements, writes the test strategy and reviews the plan with the project team.

How do you create a test strategy?

The test strategy is a formal description of how a software product will be tested. A test strategy is developed for all levels of testing. The test team analyses the requirements, writes the test strategy, and reviews the plan with the project team. The test plan may include test cases, conditions, and the test environment, a list of related tasks, pass/fail criteria and risk assessment.

Contents of Test Plan

Brief description of system.
Types of test:
Unit testing
Integration testing
Performance testing
Load/Stress testing
UAT
What to test (depends on the criticality)
What not to test
Who tests what
Tools used to testing
Schedule for testing
Acceptance Criteria
Risks
Assumptions
Test environment
Test data

Contents of Test Strategy:

Who does the testing?
What to test
When to test – Like when the module would be delivered to the test team.
Where to test – Test environment
How to test – Requires details about tools involved
Why to test
How do you know have done the testing.

Best Regards
Narasimha Murthy

PS: Please feel free to post comments and ask questions.