Unit 3.2 - Experimentation

Question 1

What is a pilot study?

Answer 1

Short experiment that are commonly carried out before starting a scientific investigation

Question 2

What is the purpose of a pilot study?

Answer 2

To develop and improve experimental protocols, ensuring the experimental design is suitable for investigation the aim

Question 3

Give advantages of pilot studies

Answer 3

• Allows a new protocol to be developed
• Ensures an appropriate range of values for the independent variable
• Allows practice of an established protocol

Question 4

What are the three type of variables?

Answer 4

Independent, Dependent, Confounding

Question 5

What is an independent variable?

Answer 5

Variable that is deliberately manipulated by the investigator to determine if it has an effect on the outcome of the experiment

Question 6

What is a dependent variable?

Answer 6

Variable that is measured to determine if changing the independent variable has an effect

Question 7

What is a confounding variable?

Answer 7

Variable, other than the independent variable that may affect the dependent variable

Question 8

What is used if confounding variables cannot be controlled effectively?

Answer 8

Randomised Block Design

Question 9

What type of sampling is Randomised Block Design?

Answer 9

Stratified Sampling

Question 10

What are the two classes of variables?

Answer 10

Discrete

Continuous

Question 11

What are discrete variables?

Answer 11

Finite values that allow placement into groups

Question 12

Give an example of a discrete characteristic

Answer 12

Sex

Question 13

What are continuous variables?

Answer 13

Values that change gradually from one extreme to another

Question 14

Give examples of qualitative data

Answer 14

Colour of leaf

Emotions

Question 15

How is qualitative data presented?

Answer 15

Bar graph

Question 16

Give examples of quantitative data

Answer 16

Time

Height

Question 17

What are the three types of data?

Answer 17

Quantitative
Qualitative
Ranked

Question 18

How is quantitative data presented?

Answer 18

Line graph/histogram

Question 19

How is ranked data presented

Answer 19

Bar graph

Question 20

What is a multi factorial experiment?

Answer 20

An experiment that is changing more than one independent variable

Question 21

Give an example of a multi factorial experiment

Answer 21

Field Studies (ecology)

Question 22

What are some advantages of simple experiments?

Answer 22

• Simpler experimental design
• Variables are tightly controlled
• Results are easy to analyse

Question 23

What are some disadvantages of simple experiments?

Answer 23

• Not suitable for testing complex hypothesis

- Difficult to extrapolate

Question 24

What are some advantages in multi factorial experiments?

Answer 24

• Allows examinations of complex interactions
• Allows generalizations to be made
• Results applicable to whole enviroments

Question 25

What are some disadvantages of multi factorial experiments?

Answer 25

• More complex and time consuming
• Difficult to control all variables
• Analysis of data is complicated

Question 26

Define ‘Precision’

Answer 26

Closeness of repeated measurements to one another

Question 27

Define ‘Accuracy’

Answer 27

Measure of how close the data is to actual true value

Question 28

Define ‘Validity’

Answer 28

Whether conclusions drawn from a set of results are credible (fair testing has taken place)

Question 29

Define ‘Reliability’

Answer 29

Whether a procedure yields consistent results each time repeated