Hadi's measure of influence based on the fact that influential observations can be present in either the response variable or in the predictors or both. The plot is used to detect influential observations based on Hadi's measure.
References
Chatterjee, Samprit and Hadi, Ali. Regression Analysis by Example. 5th ed. N.p.: John Wiley & Sons, 2012. Print.
Examples
model <- lm(mpg ~ disp + hp + wt, data = mtcars)
ols_plot_hadi(model)