MET 02 - Control of variables

Question 1

What is a confounding variables?

Answer 1

• A kind of EV that varies systematically with the IV
• Therefore we cannot tell if any change in the DV is due to the IV or the confounding variable

Question 2

What is an extraneous variable?

Answer 2

• Any variable, other than the independent variable (IV) (that are you are not investigating), that may affect the dependent variable (DV), if it is not controlled
• They are nuisance variables that do not vary systematically with the IV

Question 3

What is a demand characteristic?

Answer 3

• Any cues from the researcher or the research situation that may be interpreted by participants as revealing the aim of the study/investigation resulting to unintended changes to participants’ behaviour within the research situation.
• Demand characteristics is a form of participant reactivity

Question 4

What can demand characteristics lead to?

Answer 4

The please-U effect or the screw-U effect

Question 5

What are the types of extraneous variables?

Answer 5

• Demand characteristics
• Participant variables
• Situational variables

Question 6

What is a participant variable?

Answer 6

Characteristics of individual participants (e.g. age, sex, intelligence, marital status, religion, etc) that might influence the outcome of the study

Question 7

What is participant reactivity?

Answer 7

The tendency for participants to react to cues from the researcher or the research environment/situation

Question 8

What is the investigator effect?

Answer 8

• Any effect of the investigator’s behaviour (conscious or unconscious) on the research outcome (the DV)
• This may include anything from the design of the study to the selection of, and interaction with, the participants during the research process

Question 9

What is a situational variable?

Answer 9

Features of the immediate physical and social environment which may influence a person’s behaviour (such as proximity, location and uniform)

Question 10

What is the causal effect?

Answer 10

It is when something happens or is happening based on something that occurred or is occurring
- For example, B happened because of A
- Or the outcome of B is strong or weak because of how well or how much A worked

Question 11

What is randomisation?

Answer 11

• The use of chance methods to control for the effects of bias when designing materials, selecting samples of participants, allocating participants to tasks and deciding the order of experiment conditions, to reduce the investigator’s unconscious bias on a study
• This is a way of controlling for the effects of extraneous/confounding variables

Question 12

What is standardisation?

Answer 12

• Using exactly the same formalised procedures and instructions for all participants in a research study
• For example using standardised instructions, listing exactly what will be done in the study
• This reduces the effect of extraneous/confounding variables