2.3

These flashcards cover key terms and concepts related to correlation and linear relationships as discussed in the lecture notes.

Correlation

A statistic that measures the strength and direction of a linear relationship between two quantitative variables.

Pearson product-moment correlation coefficient

A measure that quantifies the direction and strength of the linear relationship between two quantitative variables.

r

The correlation coefficient, which ranges from -1 to 1, indicating the strength and direction of a linear relationship.

Outliers

Extreme values in data that can strongly affect the correlation coefficient.

Linear relationship

The relationship between two variables that can be represented by a straight line.

Explanatory variable

The independent variable in a study, which is manipulated to observe effects on a dependent variable.

Scatterplot

A graphical representation of the relationship between two quantitative variables, showing individual data points on a coordinate system.

Negative association

A situation in which the values of one variable decrease as the values of another variable increase, represented by a correlation coefficient less than zero.

Positive association

A situation in which the values of one variable increase as the values of another variable increase, represented by a correlation coefficient greater than zero.

r² (r squared)

The square of the correlation coefficient, representing the proportion of variation explained by the linear relationship between two variables.