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Friday, June 19, 2009

Guidelines For Matrics Calculations

Metrics Used In Testing
In this tutorial you will learn about metrics used in testing, The Product Quality Measures -

1. Customer satisfaction index,
2. Delivered defect quantities,
3. Responsiveness (turnaround time) to users,
4. Product volatility,
5. Defect ratios,
6. Defect removal efficiency,
7. Complexity of delivered product,
8. Test coverage,
9. Cost of defects,
10. Costs of quality activities,
11. Re-work,
12. Reliability and Metrics for Evaluating Application System Testing.

The Product Quality Measures:

1. Customer satisfaction index
This index is surveyed before product delivery and after product delivery (and on-going on a periodic basis, using standard questionnaires).The following are analyzed:
Number of system enhancement requests per year
Number of maintenance fix requests per year
User friendliness: call volume to customer service hotline
User friendliness: training time per new user
Number of product recalls or fix releases (software vendors)
Number of production re-runs (in-house information systems groups)

2. Delivered defect quantities
They are normalized per function point (or per LOC) at product delivery (first 3 months or first year of operation) or Ongoing (per year of operation) by level of severity, by category or cause, e.g.: requirements defect, design defect, code defect, documentation/on-line help defect, defect introduced by fixes, etc.

3. Responsiveness (turnaround time) to users
Turnaround time for defect fixes, by level of severity
Time for minor vs. major enhancements; actual vs. planned elapsed time

4. Product volatility
Ratio of maintenance fixes (to repair the system & bring it into compliance with specifications), vs. enhancement requests (requests by users to enhance or change functionality)

5. Defect ratios
Defects found after product delivery per function point.
Defects found after product delivery per LOC
Pre-delivery defects: annual post-delivery defects
Defects per function point of the system modifications

6. Defect removal efficiency
Number of post-release defects (found by clients in field operation), categorized by level of severity
Ratio of defects found internally prior to release (via inspections and testing), as a percentage of all defects All defects include defects found internally plus externally (by customers) in the first year after product delivery

7. Complexity of delivered product
McCabe's cyclomatic complexity counts across the system
Halstead’s measure
Card's design complexity measures
Predicted defects and maintenance costs, based on complexity measures

8. Test coverage
Breadth of functional coverage
Percentage of paths, branches or conditions that were actually tested
Percentage by criticality level: perceived level of risk of paths
The ratio of the number of detected faults to the number of predicted faults.

9. Cost of defects
Business losses per defect that occurs during operation
Business interruption costs; costs of work-arounds
Lost sales and lost goodwill
Litigation costs resulting from defects
Annual maintenance cost (per function point)
Annual operating cost (per function point)
Measurable damage to your boss's career

10. Costs of quality activities
Costs of reviews, inspections and preventive measures
Costs of test planning and preparation
Costs of test execution, defect tracking, version and change control
Costs of diagnostics, debugging and fixing
Costs of tools and tool support
Costs of test case library maintenance
Costs of testing & QA education associated with the product
Costs of monitoring and oversight by the QA organization (if separate from the development and test organizations)

11. Re-work
Re-work effort (hours, as a percentage of the original coding hours)
Re-worked LOC (source lines of code, as a percentage of the total delivered LOC)
Re-worked software components (as a percentage of the total delivered components)

12. Reliability
Availability (percentage of time a system is available, versus the time the system is needed to be available)
Mean time between failure (MTBF).
Man time to repair (MTTR)
Reliability ratio (MTBF / MTTR)
Number of product recalls or fix releases
Number of production re-runs as a ratio of production runs

Metrics for Evaluating Application System Testing:

Metric = Formula

Test Coverage = Number of units (KLOC/FP) tested / total size of the system. (LOC represents Lines of Code)

Number of tests per unit size = Number of test cases per KLOC/FP (LOC represents Lines of Code).

Acceptance criteria tested = Acceptance criteria tested / total acceptance criteria

Defects per size = Defects detected / system size

Test cost (in %) = Cost of testing / total cost *100

Cost to locate defect = Cost of testing / the number of defects located

Achieving Budget = Actual cost of testing / Budgeted cost of testing

Defects detected in testing = Defects detected in testing / total system defects

Defects detected in production = Defects detected in production/system size

Quality of Testing = No of defects found during Testing/(No of defects found during testing + No of
acceptance defects found after delivery) *100

Effectiveness of testing to business = Loss due to problems / total resources processed by the system.

System complaints = Number of third party complaints / number of transactions processed

Scale of Ten = Assessment of testing by giving rating in scale of 1 to 10

Source Code Analysis = Number of source code statements changed / total number of tests.

Effort Productivity = Test Planning Productivity = No of Test cases designed / Actual Effort for Design and Documentation

Test Execution Productivity = No of Test cycles executed / Actual Effort for testing