SQA LESSON 2SQA LESSON 2

Paola Di MaioPaola Di Maio

CONTENTSCONTENTS

1. Dimension/views of quality1. Dimension/views of quality 2. More about main quality parameters2. More about main quality parameters 3. The quality process3. The quality process 4. Quality and the organization4. Quality and the organization 5. The quality assurance plan (QAP)5. The quality assurance plan (QAP) . Quality vs Testing. Quality vs Testing

1. DIMENSIONS/VIEWS OF Q1. DIMENSIONS/VIEWS OF Q

TranscendentTranscendent. .

The transcendent view of quality equates quality with "innate excellence". The transcendent view of quality equates quality with "innate excellence".

User-Based.User-Based.. According to the user-based view of quality, q. According to the user-based view of quality, quality is the satisfaction of user wants or needs. If product A satisfies uality is the satisfaction of user wants or needs. If product A satisfies more user wants and needs than product B, then product A has highmore user wants and needs than product B, then product A has higher quality than product B.er quality than product B.ใ ใ 2 2 problems problems

1. d1. designing a product that simultaneously meets the needs of a diveesigning a product that simultaneously meets the needs of a diverse group of users. For example, the popular image editing program rse group of users. For example, the popular image editing program PhotoShop is used by average consumers, professional photographPhotoShop is used by average consumers, professional photographers, and high-end animation studios.. What might be satisfying to oners, and high-end animation studios.. What might be satisfying to one customer might be completely unacceptable to another.e customer might be completely unacceptable to another.

2. 2. User satisfaction is based on an aggregate of product factors--onlUser satisfaction is based on an aggregate of product factors--only one of which is quality. (See figure 6.) Just because a user is satisfy one of which is quality. (See figure 6.) Just because a user is satisfied with a product you can't conclude it is exclusively because of higied with a product you can't conclude it is exclusively because of high quality. A user might be satisfied with a low quality product if the oth quality. A user might be satisfied with a low quality product if the other factors that influence satisfaction are high enough to compensather factors that influence satisfaction are high enough to compensate for the dissatisfaction attributable to low qualitye for the dissatisfaction attributable to low quality

BEFORE BEFORE this perspective can serve as a basis for quality managementthis perspective can serve as a basis for quality management, there has to be some way of measuring the extent to which produc, there has to be some way of measuring the extent to which product quality is contributing to user satisfaction independent of other prodt quality is contributing to user satisfaction independent of other product features that might also be influencing overall user satisfaction.uct features that might also be influencing overall user satisfaction.

Conformance to requirements.Conformance to requirements.    ADVANTAGES: ADVANTAGES: When quality is defined as conformance to requirements, tWhen quality is defined as conformance to requirements, t

here is no ambiguity about what quality is. A quality product is one that confhere is no ambiguity about what quality is. A quality product is one that conforms to specified requirements and design.orms to specified requirements and design.

simplifies the production or implementation phase of the product life cycle. simplifies the production or implementation phase of the product life cycle. is a good operational definition of quality because manufactures of all types is a good operational definition of quality because manufactures of all types

of products can specify quality goals and control progress towards the accoof products can specify quality goals and control progress towards the accomplishment of these goals.mplishment of these goals.

PROBLEMS: It does not accommodate for subjective view of 'goodlness' PROBLEMS: It does not accommodate for subjective view of 'goodlness' (McDonalds vs Ritz)(McDonalds vs Ritz)..

It dIt disregardisregardss the needs of the user. Quality as conformance to requirements the needs of the user. Quality as conformance to requirements doesn't discount the importance of meeting the needs of the user, it just assdoesn't discount the importance of meeting the needs of the user, it just assumes that these needs will be represented in the requirements. umes that these needs will be represented in the requirements.

CONSTRAINTSCONSTRAINTS

3. MORE DEFINITIONS3. MORE DEFINITIONS Quality - (1) The degree to which a system, component, or process Quality - (1) The degree to which a system, component, or process

meets specified requirements. (2) The degree to which a system, comeets specified requirements. (2) The degree to which a system, component, or process meets customer or user needs or expectations. mponent, or process meets customer or user needs or expectations. [IEEE Std. 610-12-1990][IEEE Std. 610-12-1990]

.. Software Quality - the degree to which software possesses a Software Quality - the degree to which software possesses a desiredesire

dd combination of combination of attributesattributes. [IEEE Std 1061-1998] (Italics added for . [IEEE Std 1061-1998] (Italics added for emphasis.) emphasis.) 

Software Quality - degree to which the software, (1) conforms to speSoftware Quality - degree to which the software, (1) conforms to specified requirements, (2) meets the needs and expectations of custocified requirements, (2) meets the needs and expectations of customers, users and stakeholders in general (3) is designed and develomers, users and stakeholders in general (3) is designed and developed according to sound engineering practices and standards.ped according to sound engineering practices and standards.

4. QUALITY PROCESS4. QUALITY PROCESS

SOFTWARE QUALITY CYCLESOFTWARE QUALITY CYCLEwwwwww..techmatrixtechmatrix..coco..jpjp

5. MORE QUALITY CRITERIA5. MORE QUALITY CRITERIA

6. QUALITY ASSURANCE, THE PLAN6. QUALITY ASSURANCE, THE PLAN

QUALITY MANAGEMENT ACTIVITIESQUALITY MANAGEMENT ACTIVITIES

Quality Control Quality Control Quality Assurance Quality Assurance Quality Management Quality Management Defect Prevention Defect Prevention

7. TESTING 7. TESTING

OOperation of software under siperation of software under simulated conditions for the purmulated conditions for the purpose of finding defectspose of finding defects

It is an essential step in the LC It is an essential step in the LC but......but......

ttesting is performed too late in the product cycle to be an esting is performed too late in the product cycle to be an efficientefficient m method of avoiding defects. With most software development methodethod of avoiding defects. With most software development methodologies, testable code isn't produced until late in the development cyologies, testable code isn't produced until late in the development cycle. Even when doing short iterations, a lot of work is performed befcle. Even when doing short iterations, a lot of work is performed before the first line of code is written. Testing is an inefficient method of ore the first line of code is written. Testing is an inefficient method of detecting defects because the cost of finding and fixing a defect incrdetecting defects because the cost of finding and fixing a defect increases dramatically with the length of time the defect exists in the syeases dramatically with the length of time the defect exists in the system. Starting the search for defects late in the software developmestem. Starting the search for defects late in the software development life cycle increases the expense of finding and removing defects tnt life cycle increases the expense of finding and removing defects that are introduced earlier in the software development life cycle.hat are introduced earlier in the software development life cycle.

Testing is not a good approach to quality BECAUSE

Testing addresses only a narrow, although important, diTesting addresses only a narrow, although important, dimension of quality. Testing has the potential to improve tmension of quality. Testing has the potential to improve the reliability of the end product but no amount of testing he reliability of the end product but no amount of testing will improve its maintainability, extensibility, etc. These otwill improve its maintainability, extensibility, etc. These other dimensions of software quality have to be engineereher dimensions of software quality have to be engineered into the product from the beginning. d into the product from the beginning.

Only the quality of code is improved through testiOnly the quality of code is improved through testing. A software product or solution is more than jng. A software product or solution is more than just code. It also includes requirements, designs, ust code. It also includes requirements, designs, user manuals and other documentation. The supuser manuals and other documentation. The supporting documentation of a software system has porting documentation of a software system has a significant influence on the overall quality of tha significant influence on the overall quality of the system but can't be verified through testing.e system but can't be verified through testing.

The quality assurance The quality assurance manager/teammanager/team::

Works with development engineers to define appropriate Works with development engineers to define appropriate standards and procedures of software development. standards and procedures of software development.

Monitors their work through reviews and audits to verify tMonitors their work through reviews and audits to verify that these standards and procedures are being followed. hat these standards and procedures are being followed.

Provides feedback to upper management and other stakProvides feedback to upper management and other stakeholders on progress towards quality goals. eholders on progress towards quality goals.

LEARNING LEARNING TARGETS/ASSIGNMENT 2TARGETS/ASSIGNMENT 2

Describe and define the different dimensions/view of Describe and define the different dimensions/view of qualityquality

Explain the Total quality management approachExplain the Total quality management approach Discuss in detail the most common parameters for Discuss in detail the most common parameters for

quality, and give examplesquality, and give examples Define which people and processes are involved in Define which people and processes are involved in

quality assurance quality assurance Describe what is a quality assurance plan (QAP)Describe what is a quality assurance plan (QAP)

Contrast Quality vs TestingContrast Quality vs Testing

READINGREADING

TIAN, CHAP 1 AND 2TIAN, CHAP 1 AND 2 HORCH, CHAPT 1, 2HORCH, CHAPT 1, 2

Working documents:Working documents:

httphttp://://ieeexploreieeexplore..ieeeieee..orgorg//iel5/8063/22298/01040117iel5/8063/22298/01040117..pdf?pdf?arnumberarnumber==10401171040117