Extraneous variables

Question 1

What are the 3 types of extraneous variables

Answer 1

• Participant variables
• Investigator effects
• Situational variables

Question 2

What are participant variables

Extraneous variable

Answer 2

Extraneous variable
Personal characteristics of participiants
e.g gender

Question 3

What are investigator effects

or experimenter varaibles

Answer 3

Extraneous variable
Researcher influences behaviour of participants & results of study
e.g loud researcher makes participants feel intimidated
or researchers expectations of study influence their behaviour which infkuenves participant behaviour & results of study

Question 4

What are situational variables

Answer 4

Extraneous variable
features of external enviroment
e.g time of day,

Question 5

What are demand characteristics

Situational variable

Answer 5

A situational variable that act as a hints that enable participants to guess aim of study
Can be either situational variables or investigator effects

Question 6

How to participants respond to demand characteristics

Answer 6

• Behaving the way the researcher wants them to behave
• Behaving oppositely to how researcher wants them to behave

Question 7

What happens if extraneous variables are uncontrolled

Answer 7

reduces the validity & reliability of study

Question 8

one way to control extraneous variables is through standardisation explain

Answer 8

Researcher makes an extraneous variable same for all participants so that validity & reliability increase

Question 9

What extraneous variables can standardisation be used for

Answer 9

Investigator effects
Situational variables-can control factors in situation

Question 10

Controlling extraneous variables :matching

Answer 10

When researcher allocates participants to different groups in a way that makes sure a particular participant characteristics is divided equally across both groups
matching can control investigator effects

Question 11

What are the limitations of matching

Answer 11

Time-consuming as researcher has to measure personal characteristics of their participants & try & identify ppl with similar characteristics
* Cannot control every participant variable that could affects result of study

Question 12

Controlling extraneous variables:Random allocation

Answer 12

Participants are assigned at random to different groups
Random allocation-can control situational variables

Question 13

Define single blind study

Answer 13

only participants are blind to experimental group
can be used to reduce demand characteristics

Question 14

Define double blind study

Answer 14

Participants & researcher are blind to exoerimeneter group

reduces investigator effects & demand characteristics