Quality Management

Quality is about meeting the minimum standard required to satisfy customer needs.

ISO 9126

Quality in use

• Effectiveness - ability to achieve user goals with accuracy and completeness
• Productivity - avoids excessive use of resources in achieving user goals
• Safety - within reasonable levels of risk of harm to people, business, software, property, environment etc
• Satisfaction - happy users!

External Software Quality Characteristics

FEMURP * F unctionality - does it satisfy user needs? * E fficiency - relates to the physical resources used during execution * M aintainability - relates to the effort needed to make changes to the software * U sability - how easy is it to use? * R eliability - can the software maintain its level of performance? * P ortability - how easy can it be moved to a new environment?

TQM - Total Quality Management

 __________       ______________
|          |     |              |
| Focus on |     |   Improve    |
| processes|_____|_continuously |
|_________/        \____________|
         /          \
        /  Focus on  \
        \  customers /
 ________\          /______________
|         \________/               |
| Base decisions | | Let everybody |
|    on facts    | | be committed  |
|________________| |_______________|

       Committed leadership

Practical

• Quality plan
• Define criteria for activities & include inspections
• When are we done?
  • Monitoring quality levels
  • Release decision based on quality measurements

Quality Plan

A quality plan can be seen as a checklit that all quality issues have been dealt with by the planning process.

• scope of plan & references to other documents
• quality management, incl organization, tasks, and responsibilities
• documentation to be produced
• standards, practices and conventions, reviews and audits
• testing strategy and plan
• problem reporting and corrective action
• tools, techniques, and methodologies
• code, media and supplier control
• records collection, maintenance and retention
• training
• risk management - methods of risk management that are to be used

Clear criterias for activities/inspections

• Entry requirements - test data and expected results prepared
• Implementation requirements - "when error is found, do this and that"
• Exit requirements - done when all tests ok

When are we done?

It is not possible to know when there are no more errors, this has to be estimated. Using testing techniques or expert opinion.

Result

• Successful?
  • Delivered on time
  • Delivered within budget
• Gains
  • Quality product that meets customer need
  • New lessons learnt (experience, process improvements)

Summary

• Quality is a vague concept, things have to be carefully defined
• Most qualities that are apparent to users can only be tested with the complete product
• Need ways of testing during development to see how the final product will behave
• Some techniques concentrate on testing the product of the development process, while others test the process itself.