Psychology Degree Psychological Research Methods 2

Question 1

A researcher measures participants' reaction times before and after a caffeine intervention. What type of design is this?

Accepted Answer

Within-subjects design

Answer

A within-subjects design uses the same participants in all conditions, so pre- and post-measures on the same people is within-subjects.

Question 2

Which statistical concept refers to the probability of correctly rejecting a false null hypothesis?

Accepted Answer

Statistical power

Answer

Statistical power is the probability of detecting a true effect (rejecting a false null hypothesis), typically targeted at 0.80 or higher.

Question 3

In a factorial design, an interaction effect means that:

Accepted Answer

The effect of one IV depends on the level of another IV

Answer

An interaction occurs when the effect of one independent variable differs depending on the level of the other independent variable.

Question 4

What is the primary purpose of counterbalancing in within-subjects designs?

Accepted Answer

To control for order and carryover effects

Answer

Counterbalancing varies the order of conditions across participants to prevent order and carryover effects from confounding results.

Question 5

A Likert scale measuring 'strongly disagree' to 'strongly agree' is an example of which measurement level?

Accepted Answer

Ordinal

Answer

Likert scales are ordinal because responses are ranked, but intervals between points are not guaranteed to be equal.

Psychology Degree Practice Test