Cook's Distances: Cook's Distances for Linear and Generalized Linear Models
Description
This function now simply calls cooks.distance in the base package.
Usage
cookd(model, ...)
Arguments
model
lm or glm model object.
...
other arguments to be passed to cooks.distance.
Value
cookd returns a vector with one entry for each observation.
Details
Cook's distances for generalized linear
models are approximations, as described in Williams (1987) (except that the Cook's distances are
scaled as F rather than as chi-square values).
This function is retained primarily for consistency with An R and S-PLUS Companion
to Applied Regression. Other deletion diagnostics formerly in the car package have
been rewritten and moved to the base package; these include influence,
rstudent, hatvalues, dfbeta, and dfbetas.
References
Cook, R. D. and Weisberg, S. (1984)
Residuals and Influence in Regression. Wiley.
Fox, J. (1997)
Applied Regression, Linear Models, and Related Methods. Sage.
Williams, D. A. (1987)
Generalized linear model diagnostics using the deviance and single
case deletions. Applied Statistics36, 181--191.