Studentized residual plot

Graph for identifying outliers.

Usage

ols_plot_resid_stud(model, threshold = NULL, print_plot = TRUE)

Arguments

model

An object of class lm.

threshold

Threshold for detecting outliers. Default is 3.

print_plot

logical; if TRUE, prints the plot else returns a plot object.

Value

ols_plot_resid_stud returns a list containing the following components:

outliers

a data.frame with observation number and studentized residuals that exceed threshold

for classifying an observation as an outlier

threshold

threshold for classifying an observation as an outlier

Details

Studentized deleted residuals (or externally studentized residuals) is the deleted residual divided by its estimated standard deviation. Studentized residuals are going to be more effective for detecting outlying Y observations than standardized residuals. If an observation has an externally studentized residual that is larger than 3 (in absolute value) we can call it an outlier.

See also

ols_plot_resid_stand()

Examples

model <- lm(mpg ~ disp + hp + wt, data = mtcars)
ols_plot_resid_stud(model)

ols_plot_resid_stud(model, threshold = 2)