Chapter 6: Methodological Control in Experimental Research

Question 1

What is a between-subjects design?

Answer 1

participants are in group A or B

Question 2

what is a within-subjects design?

Answer 2

participants are in groups A and B

Question 3

What are the disadvantages of between-subjects designs?

Answer 3

• Large numbers of people may need to be recruited, tested, and debriefed
• Differences between conditions might be due to the independent variables or differences between individuals

Question 4

Wha are the advantages of between-subjects designs?

Answer 4

Participants are naive to the research hypothesis

Question 5

When and why do we make equivalent groups?

Answer 5

in between-subjects designs because differences between conditions might be due to the independent variables or due to differences between the individuals

Question 6

How can we create equivalent groups?

Answer 6

Via random assignment or matching techniques

Question 7

what is blocked random assignment?

Answer 7

ensures each condition has an equal amount of randomly assigned participants

Question 8

What is matching?

Answer 8

participants are grouped together based on a subject variable (matching variable) and are then randomly distributed to conditions. Good for small participant numbers.

we must be confident that the matching and dependent variables are correlated and it must be possible to assess participants on the matching variable

Question 9

What are the advantages of within-subject designs?

Answer 9

Fewer people need to be recruited
and it eliminates the equivalent groups problem

Question 10

What are the disadvantages of within-subject designs?

Answer 10

Order effects: type of sequencing effect that is a consequence of the order in which participants are administered the experimental conditions

Question 11

What are progressive effects?

Answer 11

performance changes progressively from trial to trial

Question 12

what are carryover effects?

Answer 12

some sequences produce different effects from others

Question 13

What is counterbalancing used for?

Answer 13

it controls order effects by using more than one sequence

Question 14

what counterbalancing techniques can you use if a participant is tested once for each condition?

Answer 14

complete or partial counterbalancing

Question 15

What is the difference between complete and partial (incomplete) counterbalancing?

Answer 15

in complete counterbalancing every possible sequence is used at least once
in partial counterbalancing a subset of the total number of orders is used

Question 16

How can one control order effects?

Answer 16

with counterbalancing

Question 17

what counterbalancing techniques can you use if a participant is tested more than once for each condition?

Answer 17

reverse counterbalancing and block randomisation

Question 18

what is reverse counterbalancing?

Answer 18

the conditions are presented in a certain order and then again in the reverse order

Question 19

what is block randomisation?

Answer 19

every condition must occur once before any are repeated & the order of conditions is randomised within each block

Question 20

what is a benefit of block randomisation over reverse counterbalancing?

Answer 20

it prevents participants from knowing what condition is coming next

Question 21

What are the 3 study designs used in developmental research?

Answer 21

cross-sectional, longitudinal, and cohort sequential designs

Question 22

what is the benefit of longitudinal designs over cross-sectional designs?

Answer 22

there are no cohort effects

Question 23

what is a benefit of cross-sectional over longitudinal designs?

Answer 23

they take less time

Question 24

What is experimenter bias?

Answer 24

when a researcher’s cognitive bias causes them to subconsciously influence the participants of an experiment

Question 25

How can you control for experimenter biases?

Answer 25

mechanise procedures, use protocols, or use a single-blind or double-blind procedure

Question 26

What is the difference between a single-blind and double-blind design?

Answer 26

in a double blind design neither the participant nor the experimenter know which condition the participant is in

Question 27

what is subject bias / the Hawthorne effect?

Answer 27

when knowledge about an experimental condition influences a participant’s responses or behaviour

Question 28

What are some influences on subject bias?

Answer 28

demand characteristics, evaluation apprehension, the participant’s temperament

Question 29

What are some ways to reduce subject bias?

Answer 29

• reduce demand characteristics
• use placebo control group
• perform manipulation check
• conduct field research