Research Methods: Correlational vs Experimental

Correlational Studies

Examines the relationship between two variables without manipulating them; looks at how variables vary together statistically. Problems with inferring causation due to third-variable and directionality issues.

Scientific Method - Step 1

Identifying a specific question of interest.

Scientific Method - Step 2

Formulating an explanation.

Scientific Method - Step 3

Carrying out systematic research that supports or refutes the explanation.

Directionality Problem

In correlational studies, it's unclear which variable influences the other (which is cause and which is effect).

Ethnography

A correlational research method where a researcher aims to understand values and attitudes by acting as a participant for a period of time.

Case Studies

In-depth interviews and testing with one individual or a very small group, a type of correlational research.

Psychophysiological Methods

Test for associations between physiological measures and behaviors, a type of correlational research.

Between-Subject Design

An experimental design where different participants are assigned to each condition (each participant experiences only one condition).

Within-Subject Design

An experimental design where the same participants experience all conditions; the order of conditions is typically randomized.

Demand Characteristics

Participants guessing the hypothesis of an experiment and altering their behavior accordingly.

Attrition

Participant dropout rates that differ across groups, which can threaten the validity of a study.

Order Effects

In within-subjects designs, earlier tasks or conditions influencing performance on later ones.

Floor Effects

A threat to experimental validity where participants perform at the lowest possible level regardless of the experimental condition.

Ceiling Effects

A threat to experimental validity where participants perform at the highest possible level regardless of the experimental condition.