0.8. Extraneous variables

Question 1

What are extraneous variables?

Answer 1

All variables which are not the IV but could affect the results of the experiment

Question 2

What are Participant variables?

Answer 2

How do people differ?

Question 3

What are Situational variables?

Answer 3

How can a situation differ?

Question 4

What are Participant effects?

Answer 4

How can a person effect the study?

Question 5

Participant variables explained

Answer 5

• age, intelligence, motivation, experience
• ppts in one condition may perform better than the other because of certain characteristics in common
• gender: males and females are psychologically different due to socialisation

Question 6

Situational variables explained

Answer 6

• order effects: practice or fatigue- already discussed
• time of day, temperature noise -> these factors at time of testing can act as EV -> i.e running 400m will create difference to running 400m in rain

Question 7

Participant effects explained

Answer 7

• investigator effects: any cues from an investigator that encourage certain behaviours in ppts that lead to fulfilment of investigator’s expectations
• demand characteristics: particular cues in an experiment which may communicate to ppts what is expected of them and what the investigator wants to find

Question 8

How can you deal with situational variables?

Answer 8

Research: double blind design
- neither the ppts or the experimenter knows who is receiving a particular treatment
- the procedure is utilised to prevent bias in research results
- useful for preventing bias due to demand characteristics or the placebo effect
- gives a way to reduce investigator effects as investigator is unable to unconsciously give clues to ppts as to which condition they’re in

Question 9

What are the reasons for participant effects?

Answer 9

• Ppts seek cues because they want to help/hinder the experimenter
• Hawthorne effect: ppts may change, not because of the IV but merely because they’re responding to the extra attention they may be receiving

-Social desirable bias: ppts want to present themselves in the best possible ways, therefore behave in the way they consider most socially acceptable

Question 10

How can you deal with participant effects?

Answer 10

Research: single blind design
- a research method where the researchers don’t tell ppts if they’re being given a test treatment or a control treatment - this is done in order to ensure that ppts do not bias the results by acting in ways they “think” they should act - avoids demand characteristics

Question 11

What is experimental realism?

Answer 11

The extent to which situations created in social psychology are real and impactful to ppts

Question 12

What is standardisation?

Answer 12

Using the exact same formalised procedure for all ppts in a research study -> if there is a different procedure this causes extraneous variables

Question 13

What are confounding variables?

Answer 13

• these change systematically with the IV (EVs don’t change systematically)
• a confounding variables is an unmeasured third variable that influences or “confounds” the relationship between the IV and the DV by suggesting the presence of a false relationship
• when an extraneous variables has not been properly controlled and interferes with the DV, it is called a confounding variable
• random allocation reduces the chance of these occurring