gnm (version 0.8-1)

summary.gnm: Summarize Generalized Nonlinear Model Fits

Description

summary method for objects of class "gnm"

Usage

## S3 method for class 'gnm':
summary(object, dispersion = NULL, correlation = FALSE,
                      symbolic.cor = FALSE, ...)
## S3 method for class 'summary.gnm':
print(x, digits = max(3, getOption("digits") - 3),
                            signif.stars = getOption("show.signif.stars"),
                            symbolic.cor = x$symbolic.cor, ...)

Arguments

object

an object of class "gnm".

x

an object of class "summary.gnm".

dispersion

the dispersion parameter for the fitting family. By default it is obtained from object.

correlation

logical: if TRUE, the correlation matrix of the estimated parameters is returned.

digits

the number of siginificant digits to use when printing.

symbolic.cor

logical: if TRUE, the correlations are printed in a symbolic form rather than numbers (see symnum).

signif.stars

logical. If TRUE, "significance stars" are printed for each coefficient.

...

further arguments passed to or from other methods.

Value

• summary.gnm returns an object of class "summary.gnm", which is a list with components
• call
  the "call" component from object.
• eliminate
  the "eliminate" component from object.
• family
  the "family" component from object.
• deviance
  the "deviance" component from object.
• aic
  the "aic" component from object.
• df.residual
  the "df.residual" component from object.
• iter
  the "iter" component from object.
• deviance.resid
  the deviance residuals, see residuals.glm.
• coefficients
  the matrix of coefficients, standard errors, z-values and p-values.
• dispersion
  either the supplied argument or the estimated dispersion if the latter is NULL.
• df
  a 3-vector of the rank of the model; the number of residual degrees of freedom, and number of unconstrained coefficients.
• cov.scaled
  the estimated covariance matrix scaled by dispersion (see vcov.gnm for more details).
• correlation
  (only if correlation is true) the estimated correlations of the estimated coefficients.
• symbolic.cor
  (only if correlation is true) the value of the argument symbolic.cor.

Details

print.summary.gnm prints the original call to gnm; a summary of the deviance residuals from the model fit; the coefficients of the model; the residual deviance; the Akaike's Information Criterion value, and the number of main iterations performed.

Standard errors, z-values and p-values are printed alongside the coefficients, with "significance stars" if signif.stars is TRUE.

When the "summary.gnm" object has a "correlation" component, the lower triangle of this matrix is also printed, to two decimal places (or symbolically); to see the full matrix of correlations print summary(object, correlation = TRUE)$correlation directly. The standard errors returned by summary.gnm are scaled by sqrt(dispersion). If the dispersion is not specified, it is taken as 1 for the binomial and Poisson families, and otherwise estimated by the residual Chi-squared statistic divided by the residual degrees of freedom. For coefficients that have been constrained or are not estimable, the standard error is returned as NA.

See Also

gnm, summary

Examples

##  Following on from example(gnm)
data(cautres)
set.seed(1)

##  Fit model as before
doubleUnidiff <- gnm(Freq ~ election:vote + election:class:religion +
                     Mult(Exp(election), religion:vote) +
                     Mult(Exp(election), class:vote), family = poisson,
                     data = cautres)

## Summarize results
summary(doubleUnidiff)