Types of Correlation

A researcher is examining the statistical association between several pairs of variables. Which of the following numerical values represents the strongest association between two variables?

Correlation Matrix

Pearson's r Formula

Restriction of Range

Identifying the Weakest Correlation

Statistical Regression

Test of the Correlation Coefficient

Example of Scatterplots for Pearson's r Values

Cohen's Guidelines for Interpreting Pearson's r

Which of the following best describes the function of a correlation coefficient in psychological research?

A researcher studying stress and academic performance obtains a correlation coefficient of r = −0.82. Because the value is negative, this result indicates a weak relationship between the two variables.

A psychological research team has conducted four different correlational studies. Match each obtained Pearson’s $r$ correlation coefficient with the research finding that best represents that specific relationship.

A psychological researcher is evaluating four separate studies to determine which relationship allows for the most accurate predictions between two variables. Arrange the following Pearson’s $r$ values in order from the coefficient representing the least predictable linear association to the one representing the most predictable linear association.

A student researcher evaluates a study result where Pearson's $r = -0.75$ and concludes it represents a 'weak' relationship because the value is negative. To critique this evaluation, a supervisor would explain that the ____ of the correlation coefficient, rather than its sign, indicates the strength of the linear association.