3/17 - Residuals and other review for Statistics

Front

What is a residual in statistics?

Back

A residual is the difference between the actual value of a data point and the predicted value from a regression model.

Front

How do you calculate the predicted value using residuals?

Back

Predicted value = Actual value - Residual.

Front

What does a correlation coefficient of r = 0.89 indicate?

Back

It indicates a strong positive linear relationship between the two variables.

Front

What does a correlation coefficient of r = -0.89 indicate?

Back

It indicates a strong negative linear relationship between the two variables.

Front

What does a correlation coefficient of r = 0 mean?

Back

It indicates no linear relationship between the two variables.

Front

What is the purpose of a residual plot?

Back

A residual plot is used to assess the fit of a regression model by plotting residuals on the y-axis and predicted values on the x-axis.

Front

What does it mean if a residual plot shows a random scatter?

Back

It suggests that a linear regression model is appropriate for the data.

Front

What is the line of best fit?

Back

The line of best fit is a straight line that best represents the data on a scatter plot, minimizing the distance between the line and the data points.

Front

How can you identify the line of best fit on a scatter plot?

Back

The line of best fit can be identified as the line that has the least total distance from all points in the scatter plot.

Front

What is the significance of the slope in a linear regression equation?

Back

The slope indicates the rate of change of the dependent variable for each unit change in the independent variable.