InProcess Metrics Software Quality Metrics By Simrit Pal Singh

1
In-Process Metrics Software Quality Metrics
BySimrit Pal Singh

• PresentationforTerm PaperSoftware Engineering
  II

2
Introduction

• Software metrics
• Categories
• Software quality metrics
• In-process metrics
• Basic measures
• Derived metrics
• Industry implementation

3
Software Metrics
4
Categories

• Product Metrics
• Process Metrics
• Project Metrics

5
Categories

• Product metrics
• Describe the characteristics of the product such
  as size, complexity, design features,
  performance, and quality level.

6
Categories

• Process metrics
• Help to improve software development and
  maintenance
• Defect removal during development
• Pattern of defect arrival
• Response time of the fix process

7
Categories

• Project metrics
• Describe the project characteristics and
  execution
• Number of software developers
• Staffing pattern
• Cost
• Schedule
• Productivity

8
In-Process Metrics

• Product metrics
• Process metrics
• Project metrics

• In-Process Metrics

Software Quality Metrics
9
In-Process Quality Metrics

• Important role in S/W development
• Track Defects
• Removal of Defects
• Quality management

10
Basic Measure 1

• Defects
• Log every defect
• Containing artifact
• Type
• Phase of detection
• Phase of removal
• Effort
• Diagnosis
• Rework
• Re-testing

11
Basic Measure 2

• Effort
• Quality planning
• Test planning
• Reviews
• Compile
• Testing

12
Basic Measure 3

• Size
• Size of Defect
• Size of module/object
• LOC

13
Derived Metrics
14
Defect Density

• Defect Density Defects per
  KLOC/Function points

15
Defect Injection Rate

• Number of defects injected in phase
• Size of objects produced in the phase
• Number of defects injected
• Size of Software produced

Defect Injection rate for a phase
Defect Injection rate for project
16
Defect arrival pattern
17
Phase-based defect removal pattern

• The phase-based defect removal pattern is an
  extension of the test defect density metric. In
  addition to testing, it requires the tracking of
  defects at all phases of the development cycle,
  including the design reviews, code inspections,
  and formal verifications before testing.

18
Defect Removal Yields

• No. of defects removed in phase
• No. of defects existing at beginning of
  ph
• No. of defects removed before unit test
• Total No. of defects removed

Defect removal yield for a phase
100
Defect removal yield for project
100
19
Defect removal efficiency

• Number of defects removed in phase
• Hours of Effort expended in the phase

Defect removal efficiency for a phase

20
Motorola Quality Policy for Software Development
(QPSD)

• Goal 1 Improve project planning.
• Goal 2 Increase defect containment.
• Goal 3 Increase software reliability.
• Goal 4 Decrease software defect density.
• Goal 5 Improve customer service.
• Goal 6 Reduce the cost of nonconformance.
• Goal 7 Increase software productivity.

21
Goal 4 Decrease Software Defect Density

• In-process Faults (IPF)
• In-process faults caused by
  incremental software development
• 
  Assembly-equivalent delta source size

IPF
22
Goal 4 Decrease Software Defect Density

• In-process Defects (IPD)
• In-process defects caused by
  incremental software development
• 
  Assembly-equivalent delta source size

IPD
23
Goal 4 Decrease Software Defect Density

• Total Released Defects (TRD) total
• 
  Number of released defects
• 
  Assembly-equivalent total source size

TRD total
24
Goal 4 Decrease Software Defect Density

• Total Released Defects (TRD) delta
• Number of released defects caused
  by
• incremental software development
• 
  Assembly-equivalent total source size

TRD delta
25
Goal 4 Decrease Software Defect Density

• Customer-Found Defects (CFD) total
• Number of
  customer -found defects
• 
  Assembly-equivalent total source size

CFD total
26
Goal 4 Decrease Software Defect Density

• Customer-Found Defects (CFD) delta
• Number of customer -found
  defects caused by
• incremental software development
• 
  Assembly-equivalent total source size

CFD delta
27
Future Work for Paper

• Define In-Process Metrics
• Quality
• Design some effective In-Process Metrics
• Quantify
• Industrial Applications
• Motorola
• HP
• IBM

28
References

• Metrics and Models in Software Quality
  Engineering
• By Stephan H Kan
• In-process metrics for software testing
• S H Kan, J Parrish, D Manlove
• Software Quality Data. Basic and derieved
  measures
• Early Estimation of Software Quality Using
  In-Process Testing Metrics. Nachiappan Nagappan
• Using In-Process Testing Metrics to Estimate
  Software Reliability. Nachiappan Nagappan
• http//www.research.ibm.com/journal/