Research Methods: Experimental Design

Flashcards covering key vocabulary and concepts related to experimental design, including independent groups, repeated measures, and matched pairs designs, along with their evaluations.

Independent Groups

Two separate groups of participants experience two different conditions of the experiment. The results from the two groups are then compared.

Experimental Condition (or group)

One of the two different conditions that separate groups of participants experience in an independent groups experimental design.

Control Condition (or group)

One of the two different conditions that separate groups of participants experience in an independent groups experimental design.

Repeated Measures

All participants experience both the Experimental Condition and the Control Condition. Sets of data from both conditions are compared to see if there is a difference.

Matched Pairs

Participants are matched to someone who is like them, based on IQ, occupation, age, weight, etc. One participant from each pair is then given the Experimental Condition, the other the Control Condition.

Random Allocation

Ensures that each participant has an equal chance of being assigned to one group or the other in an experiment.

Independent Groups – Strengths

No issue with order effects.

Independent Groups – Weaknesses

Participant variables - the participants in each group aren't the same so will have individual differences. Twice as many participants are required to produce the same data you'd get from Repeated Measures.

Repeated Measures - Strengths

Participant variables are controlled. Fewer participants needed.

Repeated Measures - Weaknesses

Order effects: Could be due to many things, boredom, continuing effects of experimental condition. Higher chance of Demand Characteristics

Counterbalancing

Used to control order effects in repeated measures designs.

Matched Pairs - Strengths

Less likely to experience Demand Characteristics or Order effects. Reduces participant variables because Participants have been matched.

Matched Pairs - Weaknesses

Very time consuming and expensive. Still have the possibility of participant variables because Participants cannot be matched exactly.

Experimental Design

A method for planning and conducting scientific research that ensures reliable and valid results.