Experimental Designs Flashcards
What is the matched pairs design?
Using different participants but trying to match them in each condition in any important characteristics that might affect their performance
What is the independent measures design?
Using different participants in each part of the experiment
What is the repeated measures design?
Using the same participants in different conditions of the experiment
What are the strengths of the matched pairs design?
Subject variables are kept constant between the conditions because they’re similar people
Order effects do not occur because the subjects only participate once
Demand characteristics are less of a problem as the subject only participates in one condition
What are the weaknesses of the matched pairs design?
Subject variables are never perfectly matched, because they’re not the same person
Matching subjects is time consuming and difficult
More subjects are required because they’re only used once, it is less economical
What are the strengths of the independent measures design?
Order effects such as fatigue and boredom don’t influence a second condition because the subject only participated in one condition
Demand characteristics are less of a problem as the subject only participates in one condition so is less likely to guess the aim of the study and act differently
What are the weaknesses of the independent measures design?
Subject variables differ which could become confounding variables unless controlled for
For example - a participant could be smarter than the other
More subjects are required because they’re used once, it is less economical
What are the strengths of the repeated measures design?
Subject variables which could become extraneous variables are kept constant between conditions
Fewer subjects are required because they’re used more than once, it is more economical
What are the weaknesses of the repeated measures design?
Order effects such as fatigue and boredom may become errors when a condition is done one after another
Demand characteristics may become a problem because the subject does both conditions of the experiment, so they may guess the aim of the study
What types of experimental designs are there?
Independent
Matched
Repeated
