residuals.ols {Design}R Documentation

Residuals for ols

Description

Computes various residuals and measures of influence for a fit from ols.

Usage

## S3 method for class 'ols':
residuals(object, 
      type=c("ordinary", "score", "dfbeta", "dfbetas", 
             "dffit", "dffits", "hat", "hscore"), ...)

Arguments

object object created by ols. Depending on type, you may have had to specify x=TRUE to ols.
type type of residual desired. "ordinary" refers to the usual residual. "score" is the matrix of score residuals (contributions to first derivative of log likelihood). dfbeta and dfbetas mean respectively the raw and normalized matrix of changes in regression coefficients after deleting in turn each observation. The coefficients are normalized by their standard errors. hat contains the leverages — diagonals of the ``hat'' matrix. dffit and dffits contain respectively the difference and normalized difference in predicted values when each observation is omitted. The S lm.influence function is used. When type="hscore", the ordinary residuals are divided by one minus the corresponding hat matrix diagonal element to make residuals have equal variance.
... ignored

Value

a matrix or vector, with places for observations that were originally deleted by ols held by NAs

Author(s)

Frank Harrell
Department of Biostatistics
Vanderbilt University
f.harrell@vanderbilt.edu

See Also

lm.influence, ols, which.influence, naresid

Examples

set.seed(1)
x1 <- rnorm(100)
x2 <- rnorm(100)
x1[1] <- 100
y <- x1 + x2 + rnorm(100)
f <- ols(y ~ x1 + x2, x=TRUE, y=TRUE)
resid(f, "dfbetas")
which.influence(f)

[Package Design version 2.0-12 Index]