1.3 Testing Principles

Question 1

Testing Principles:
1. Testing shows the “p…”, not “ “ of “d…”.

Answer 1

presence
absence
defects.

Question 2

Testing reduces the probability of defects remaining “ “ in the t…

But even if no defects are found “ “ can’t prove t…

Answer 2

undiscovered
test object.

testing
test object correctness.

Question 3

Testing Principles:
2. Exhaustive “ “ is “i…”.

Answer 3

testing
impossible.

Question 4

Rather than attempting to test exhaustively:
- test t…
- test c…
- risk-b… should be used to focus t…

Answer 4

• test techniques
• test case prioritization
• risk-based testing
  test efforts.

Question 5

Testing Principles:
3. Early “t…” saves “ “ and “m…”.

Answer 5

testing
time
money

Question 6

Defects removed “e…” in the “ “ will not cause subsequent “d…” in d…

Answer 6

early
process
defects
derived work products.

Question 7

Quality cost will be “r…” since fewer “ “ will occur “l…” in the “ “.

Answer 7

reduced
failures
later
SDLC

Question 8

To find defects early s… and d… should be started as s…

Answer 8

Static testing
dynamic testing
soon as possible.

Question 9

Testing Principles:
4. Defects c…

Answer 9

cluster together.

Question 10

A small number of s… usually contain most of the d… or are responsible for most of the o…

Answer 10

system components
discovered defects
operational failures.

Question 11

Illustrated example of P…

Answer 11

Pareto principle.

Question 12

Predicted defect clusters and actual defect clusters observed during “ “ or i… are important input for r…

Answer 12

testing
in operation
risk-based testing.

Question 13

Testing Principles:
5. Tests w…

Answer 13

wear out.

Question 14

If the same tests are “r…” many times, they become increasingly “ “ in detecting new “d…”.

Answer 14

repeated
ineffective
defects.

Question 15

To overcome this effect, existing “t…” and t… may need to be “m…” and new tests may need to be “ “.

Answer 15

tests
test data
modified
written

Question 16

However, in some cases repeating the same “ “ can have a b… e.g. in automated r…

Answer 16

tests
beneficial outcome,
regression testing.

Question 17

Testing Principles:
6. Testing is c…

Answer 17

context dependent.

Question 18

Testing is done differently in d…

Answer 18

different contexts.

Question 19

Testing Principles:
7. Absence-of-…

Answer 19

defects fallacy.

Question 20

It is a fallacy (i.e. a misconception) to expect that s… will ensure s…

Answer 20

software verification
system success.

Question 21

Thoroughly testing all the specified requirements and fixing all the defects found could still produce a system that:
- does not fulfill the u… and “ “
- does not help in achieving the c…
- is inferior compared to other c…

Answer 21

• users’ needs
  expectations
• customer’s business goals
• competing systems

Question 22

In addition to verification, “ “ should also be c…

Answer 22

validation
carried out.