Term
Experimental Design
What is experimental design?
Answer
Definition
The method of allocating participants to conditions to address research questions and control confounding variables.
The three primary methods for allocating participants across experimental conditions.
Strengths and Weaknesses: Already discussed but important to consider why a design is chosen.
A key method used to minimize order effects in studies where participants repeat tasks.
Simple techniques to further reduce confounding variables.
What is experimental design?
The method of allocating participants to conditions to address research questions and control confounding variables.
What are independent groups designs?
Different participants assigned to each condition.
What is a repeated measures design?
The same participants take part in all conditions.
Describe matched pairs design.
Participants are paired based on key variables, with each pair split across conditions.
What are order effects?
When the order of conditions affects participants’ performance, e.g., due to fatigue or practice.
How does counterbalancing help in experimental design?
It controls order effects by varying the sequence of conditions between participants.
What is complete counterbalancing?
Using all possible orders of conditions, evenly assigned to participants.
What is partial counterbalancing (Latin Square)?
Using only select orders so each condition appears equally often in each position.
Name two other control measures besides counterbalancing.
Randomisation of condition order and rest intervals between conditions.
Why choose one design type over another?
To balance control, practicality, and to minimize confounding variables specific to the research question.