Psychological Research Methods Flashcards

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

Answer: Within-subjects design

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

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

Answer: Statistical power

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

In a factorial design, an interaction effect means that:

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

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

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

Answer: To control for order and carryover effects

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

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

Answer: Ordinal

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

Which type of validity concerns whether a study's findings can be generalized to other populations and settings?

Answer: External validity

External validity refers to the degree to which study results can be generalized beyond the specific study sample and setting.

When a researcher unknowingly treats experimental and control group participants differently, this is called:

Answer: Experimenter bias

Experimenter bias occurs when the researcher's expectations inadvertently influence how participants are treated or how data are interpreted.