Prob & Stats: Review for Unit 2 Test - Linear Regression

Front

What is the linear regression equation used for?

Back

To model the relationship between two variables and make predictions based on that relationship.

Front

What does the slope in a linear regression equation represent?

Back

The rate of change of the dependent variable (y) for each unit increase in the independent variable (x).

Front

How do you interpret the y-intercept in a linear regression equation?

Back

It represents the predicted value of y when x is 0.

Front

What is a correlation coefficient?

Back

A statistical measure that describes the strength and direction of a relationship between two variables.

Front

What does a correlation coefficient of r = 0.99 indicate?

Back

A very strong positive linear relationship between the two variables.

Front

What does a correlation coefficient of r = -0.99 indicate?

Back

A very strong negative linear relationship between the two variables.

Front

What is a scatter plot?

Back

A graphical representation of the relationship between two quantitative variables.

Front

What is a residual plot?

Back

A graph that shows the residuals on the vertical axis and the independent variable on the horizontal axis, used to assess the fit of a regression model.

Front

What does it mean if a scatter plot shows a linear trend?

Back

It indicates that there is a linear relationship between the two variables being plotted.

Front

How do you use a linear regression equation to make predictions?

Back

By substituting the value of the independent variable (x) into the equation to solve for the dependent variable (y).