This is a convenient interface to procedures from the lpSolveAPI package, if this package is installed (otherwise a cruder approach and possibly flawed will be used), to test for (quasi-)separation. This is used by default by the fitting funtions, but can also be called explicitly by the user to check bootstrap samples (see Example in anova
).
is_separated(x, y, verbose = TRUE)
Design matrix for fixed effects.
Numeric response vector
Whether to print some messages or not.
Returns a boolean; TRUE
means there is (quasi-)separation.
Konis, K. 2007. Linear Programming Algorithms for Detecting Separated Data in Binary Logistic Regression Models. DPhil Thesis, Univ. Oxford.
See also the 'safeBinaryRegression' package.