Year 11 · ICT · Summer 2

After the exams · Lesson 4 of 5

Build and show

Project7.3 Development and testing7.6 Evaluation

Year 11 · ICT · After the exams · Lesson 4 of 5

You will learn to

Test the finished project and record the results.
Evaluate the project against your success list and your audience's needs.
Demonstrate the project to the class and explain one problem you solved.

Year 11 · ICT · After the exams · Lesson 4 of 5

Success criteria

You have got it when you can say:

I can show which lines of my success list are met, and which are not.
I can name one improvement I would make with more time.
I can present my project and answer one question about it.

Year 11 · ICT · After the exams · Lesson 4 of 5

Retrieval starter

Questions from before. Write your answers, then show them.

Last unit
Keeping the aspect ratio means…

A The image is croppedB Width and height change together so nothing stretchesC Only the width changes

B. Width and height change together so nothing stretches
Earlier this year
Landscape orientation is…

A SquareB Taller than it is wideC Wider than it is tall

C. Wider than it is tall
Last year
In mail merge, the master document holds…

A The list of namesB The envelopeC The letter with the merge fields

C. The letter with the merge fields

Year 11 · ICT · After the exams · Lesson 4 of 5

Key words (1 of 4)

Questionnaire: A set of written questions given to many people to collect their views.
System specification: A list of the hardware and software the new system needs.
Field: One item of data in a record, such as Surname.
Validation: An automatic computer check that data is sensible and allowed.

Year 11 · ICT · After the exams · Lesson 4 of 5

Key words (2 of 4)

Check digit: An extra digit calculated from the other digits, used to detect input errors.
Data capture form: A paper or on-screen form used to collect data.
Test plan: A table listing each test, its data, the expected and actual outcomes and any remedial action.
Normal data: Sensible data that should be accepted.

Year 11 · ICT · After the exams · Lesson 4 of 5

Key words (3 of 4)

Abnormal data: Data that should be rejected, such as out of range or the wrong type.
Extreme data: Data at the limits of the allowed range, which should be accepted.
Live data: Real data from the organisation, used to test the system with known results.
Remedial action: What was done to fix a test that failed.

Year 11 · ICT · After the exams · Lesson 4 of 5

Key words (4 of 4)

Evaluation: Judging the finished system against the original requirements after it has been used.

7.3 Development and testing · The explanation · step 1 of 6 · part 1 of 2

Why test, and the test strategy

Development means building the system: creating the file structures, forms, validation and reports.

Testing checks that the system works as the design says, and that it handles mistakes without crashing.

A test strategy decides what is tested and in what order: each module (a separate part), then each function (one task, such as 'record a loan'), then the whole system working together.

7.3 Development and testing · The explanation · step 1 of 6 · part 2 of 2

Why test, and the test strategy (continued)

e.g.Example

Library system modules: member records, book records, loans, reports. Test the loans module alone first. Then test the function 'return a book'. Then test the whole system: a new member borrows a book, returns it late, and appears on the overdue report.

?Why?

Testing small parts first makes errors easy to find. If the whole system fails at once, the fault could be anywhere.

7.3 Development and testing · The explanation · step 2 of 6 · part 1 of 3

Types of test data

Normal data is sensible data that the system should accept.

Abnormal data is data that should be rejected: outside the range or the wrong type. Some books call it erroneous data.

Extreme data is data at the very limits of what is allowed. It should be accepted.

Computer Science 0478 also uses boundary data: the limit value and the value immediately beyond it. ICT 0417 asks for normal, abnormal and extreme.

7.3 Development and testing · The explanation · step 2 of 6 · part 2 of 3

Types of test data (continued)

Field rule	Normal	Extreme	Abnormal
Exam mark 0 to 100	56, 73	0, 100	101, −5, 'sixty'
Year group 7 to 13	9, 11	7, 13	6, 14, 'ten'
Loan length 1 to 21 days	14	1, 21	0, 22, 3.5

7.3 Development and testing · The explanation · step 2 of 6 · part 3 of 3

Types of test data (continued)

e.g.Example

Try the toy with the range 1 to 100. Classify 50, 1, 100, 0, 101 and 'abc'. Notice that 1 and 100 are extreme and accepted. 0 and 101 are rejected. ICT calls them abnormal. The toy labels them boundary, the Computer Science term for the value just outside the range.

!Watch out

Extreme data is accepted. Students often think extreme means 'too big'. Too big is abnormal.

There is something to try for this step in the IGCSE library.

7.3 Development and testing · The explanation · step 3 of 6 · part 1 of 3

The test plan

A test plan is a table written before testing. Each row is one test.

The first columns are: what is being tested, the test data and the type of data.

Then come the expected outcome (what should happen), the actual outcome (what did happen) and the remedial action (what was done to fix a failure).

If the actual outcome matches the expected outcome, the test passes. If not, the system is fixed and the test is run again.

7.3 Development and testing · The explanation · step 3 of 6 · part 2 of 3

The test plan (continued)

Test	Test data	Type	Expected outcome	Actual outcome	Remedial action
Mark field range 0 to 100	56	Normal	Accepted	Accepted	None needed
Mark field range 0 to 100	0	Extreme	Accepted	Accepted	None needed
Mark field range 0 to 100	100	Extreme	Accepted	Rejected with error	Changed rule from <100 to <=100, retested: accepted
Mark field range 0 to 100	101	Abnormal	Rejected, error message 'Mark must be 0 to 100'	Rejected, message shown	None needed
Mark field range 0 to 100	sixty	Abnormal	Rejected, error message 'Enter a number'	Accepted and saved	Added type check, retested: rejected
Surname presence check	(left blank)	Abnormal	Rejected, 'Surname is required'	Rejected, message shown	None needed

7.3 Development and testing · The explanation · step 3 of 6 · part 3 of 3

The test plan (continued)

?Why?

Writing the expected outcome before testing stops the tester accepting whatever happens. The test plan also becomes evidence in the technical documentation.

7.3 Development and testing · The explanation · step 4 of 6 · part 1 of 2

Live data

Live data is real data from the organisation, such as last month's actual library loans.

After testing with made-up test data, the system is tested with live data whose results are already known from the old system.

If the new system gives the same results as the old one, it is working correctly with real-world data.

7.3 Development and testing · The explanation · step 4 of 6 · part 2 of 2

Live data (continued)

e.g.Example

The library enters last October's 1,240 real loans. The old card system recorded 63 overdue books. The new system's overdue report should also show 63.

!Watch out

Live data contains real personal data, so it must be kept secure during testing.

7.6 Evaluation · The explanation · step 5 of 6 · part 1 of 2

What evaluation checks

Evaluation happens after the system has been in use for a while. It asks: does the new system do the job well?

Efficiency: is it faster or cheaper than the old system? Does it use fewer resources?

Ease of use: can staff use it with little training? Do they make fewer mistakes?

Appropriateness: is it the right solution for this organisation and its problems?

7.6 Evaluation · The explanation · step 5 of 6 · part 2 of 2

What evaluation checks (continued)

e.g.Example

Library evaluation after one term: A loan now takes 12 seconds (requirement: under 30 seconds). Met. Overdue books fell from 63 a month to 18. Improvement. Two librarians find the reports menu confusing. Ease-of-use problem.

The explanation · 1 more step

Build and show

You will learn to

Success criteria

Retrieval starter

Key words (1 of 4)

Key words (2 of 4)

Key words (3 of 4)

Key words (4 of 4)

Why test, and the test strategy

Why test, and the test strategy (continued)

Types of test data

Types of test data (continued)

Types of test data (continued)

The test plan

The test plan (continued)

The test plan (continued)

Live data

Live data (continued)

What evaluation checks

What evaluation checks (continued)

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