Understanding Correlation in Psychology Research

Which term refers to the measurement of the extent to which pairs of related values of two variables tend to change together?

In a positive correlation, what happens as one variable tends to increase?

What type of relationship is described as when one variable increases, so does the other variable, but only up to a certain point?

In which type of curvilinear relationship do both variables increase together up to a certain point?

What is the primary focus of correlational methods in research?

What distinguishes an experimental method from a correlational method?

What is a key difference between experimental and correlational research?

Which type of study is best for generalizing conclusions to other populations or settings?

What is one common way to collect data for a correlational study?

How are variables treated in a correlational study compared to an experimental study?

What type of analysis is commonly used to determine the association between variables in a correlational study?

Which type of research allows for drawing conclusions about cause-and-effect relationships?

Correlation

Correlation is the measurement of the extent to which pairs of related values of two variables tend to change together or co-vary.
Positive correlation: one variable tends to increase with the other variable.
Negative correlation: one variable tends to decrease as the other variable increases.

Types of Correlation

Curvilinear relationship: when one variable increases, the other variable increases up to a certain point, after which, the other variable decreases.
Inverted U-shaped curve: graph representation of a curvilinear relationship where one variable increases, the other variable increases up to a certain point, then decreases.
U-shaped curve: graph representation of a curvilinear relationship where one variable increases, the other variable decreases up to a certain point, then both variables increase together.

Research Methods

Experimental methods: used to test cause-and-effect relationships between variables.
Correlational methods: used to test the association between variables.

Experimental vs Correlational Research

Experimental research:
- Manipulates an independent variable and measures a dependent variable.
- Controls extraneous variables to ensure high internal validity.
- Allows for conclusions about causality.
Correlational research:
- Observes variables without manipulation.
- Limited control over extraneous variables.
- High external validity, allows for generalizability to other populations or settings.

Correlational Study

A correlational study has no manipulation by the researcher and yields statistical results.
Common data collection techniques: questionnaires, surveys, and psychometric tests (e.g. IQ tests, measures of depressive symptoms, and tests of attitudes).
Data is typically plotted on a scatterplot and analyzed using regression analysis to determine the line-of-best fit.

Learn the difference between a correlation and correlational study in psychology research. Explore how correlation is measured and identified, including positive and negative correlations between variables.