4.2.3.1 VARIABLES

Question 1

what is a variable?

Answer 1

• any ‘thing’ that can vary or change within an investigation
• generally used in experiments to determine if changes in one thing result in change in another

Question 2

what’s the independent variable?

Answer 2

• some aspect of the experimental solution that’s manipulated by the researcher (or changes naturally)
• the effect on the DV can therefore me measured
• is assumed to have a direct effect on the DV

Question 3

what’s the dependent variable?

Answer 3

• the variable that’s measured by the researcher
• any effect on the DV should be caused by the change in the IV
• is ‘dependent’ on the IV

Question 4

how can we control the dependent variable?

Answer 4

1) deception:
- lying about the aims of the study and/or using distracting questions

2) single blind design:
- participant is unaware of which condition they’re in or the research aims
- this prevents the participant from seeking clues about the aims and reacting to them

Question 5

what is operationalisation?

Answer 5

• clearly defining variables in terms of how they can be measured

Question 6

what are extraneous variables?

Answer 6

• any variable (other than the IV) that may have an effect on the DV if it’s not controlled
• they’re nuisance variables that don’t vary systematically with the IV
• when not controlled by the experimenter, they become confounding variables that can damage the validity of the experiment

Question 7

what are confounding variables?

Answer 7

• any variable (other than the IV) that may have affected the DV so we can’t be sure of the source of changes to the DV
• vary systematically with the IV

Question 8

there are 4 types of extraneous variables
what are these?

Answer 8

1) situational variables

2) participant variables

3) experimenter / investigator effects

4) demand characteristics

Question 9

what are situational variables?

Answer 9

• aspects of the environment that might affect the participant’s behaviour
• should be controlled so they are the same for all ppts
• standardised procedures are used to ensure that conditions are the same for all ppts
  -> this includes the use of standardised instructions

Question 10

what are ppt variables?

Answer 10

aka individual differences

• the ways in which each ppt varies from one to the other
• and how this could affect the results

can be controlled
- using random allocation to the conditions of the IV

Question 11

what’s the screw-you effect?

Answer 11

• when they deliberately try to hinder the experiment