sqe(lecture 5)

8/6/2019 SQE(Lecture 5)

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Metrics

Q: What is metric?

A quantitative measure of the degree to which a

system, component, or process possesses a given

attributes.


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Software Metrics

Software metrics provide a quantitative measure for

the development and validation of software.

It relates the individual measures in a software

development process.

ex: Average number oferror found per review or

the average number oferror found per unit test.

USES:It can be used to improve software productivity and

quality


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Indicator

An indicator is a metric or combination of metrics that

provides insight into the software development

process, a software project or the product itself.

A software engineer collects measure and develops

metrics so that indicator will be obtained.


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Software metrics can be classified into three

categories:

1) Product metrics.

2) Process metrics.

3) Project metrics.


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Product metrics

Product metrics describe the characteristic of thefollowing.

1) Product size.

2) Complexity.

3) Design features.

4) Performance.

5) Quality Level.


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Process Metrics

It can be used to improve software development

and maintenance.

Example:: 1) Defect removal during software

development.

2) The pattern of testing defect arrival, their response

and the time required to fix them.


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Project Metrics

It describes the project characteristics and

execution.

Example:: 1) The number of software developer

needed.

2) Their skill levels.

2) Cost of the project.

3) Schedule and productivity.


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Software Quality Metrics.

Software Quality metrics are a subset of software

metrics that focuses on the quality aspects of the

product, process and project.

Software Quality metrics are more closely associated

with process and product metrics.


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Software quality metrics can be divided further into

1) End-product quality metrics

2) In-process quality metrics.


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End Product Quality Metrics:

End-product quality is usually measured by the number

of "bugs" (functional defects) in the software or by

how long the software can run before a critical failure

(a "crash.").


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In-Process quality metrics used to measure duringdevelopment process.

Ex: In-Process Quality during Development (derived

by linking bugs to application objects)

1) Defect Density: Number of defects / Size

of application

2) Source of Defects: Number of Defects

originating in each phase3) Requirements Quality: Number of Defects

originating in Requirements phase


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Software Documents

A written document to develop a software product

produced in response to a request for tenders by an

external client.

The documents associated with a software project

being developed have a number of associated

requirements:


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They should act as a communication medium

between members of the development team.

They should provide information for management to

help them plan, budget and schedule the software

development process.

Some of the documents should tell users how to use

and administer the system.


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Documentation produced falls into two classes.

1) Process documentation.

2) Product documentation


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Process documentation:

These documents record the process of

development and maintenance.

Example of Process documentation are

1) Planning

2) scheduling.


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Product documentation:

This documentation describes the product that is

being developed. System documentation describes the product from

the point of view of the engineers developing and

maintaining the system.

User documentation provides a product description

that is oriented towards system users