Summary Method for Nonlinear Heteroscedastic Models
Returns a summary list for a fitted nonlinear heteroscedastic model.
## S3 method for class 'nlreg'
summary(object, observed = TRUE, correlation = FALSE,
digits = NULL, ...)object |
a fitted |
observed |
logical argument. If |
correlation |
logical argument. If |
digits |
the number of significant digits to be printed. |
... |
absorbs any additional argument. |
This function is a method for the generic function
summary for class nlreg. It can be
invoked by calling summary for an object of the appropriate
class, or directly by calling summary.nlreg regardless of
the class of the object.
A list is returned with the following components:
coefficients |
a matrix with four columns, containing the MLEs of the regression coefficients, their standard errors, the z-value (or Wald statistic) and the associated p-value based on the standard normal approximation to the distribution of the z statistic. |
varPar |
a matrix with two columns, containing the MLEs of the variance parameters and their standard errors. |
offset |
a numerical vector with a single named element indicating the parameter of interest and the value to which it was fixed while fitting the nonlinear model. |
residuals |
the response residuals from the fit. |
covariance |
the (asymptotic) covariance matrix for the parameter estimates. |
correlation |
the (asymptotic) correlation matrix for the parameter estimates. |
logLik |
the log likelihood from the fit. |
call |
an image of the call that produced the |
digits |
then number of significant digits to be printed. |
ws |
the |
data(metsulfuron)
metsulfuron.nl <-
nlreg( formula = log(area) ~ log( b1+(b2-b1) / (1+(dose/b4)^b3) ),
weights = ~ ( 1+dose^exp(g) )^2, data = metsulfuron,
start = c(b1 = 138, b2 = 2470, b3 = 2, b4 = 0.07, g = log(0.3)),
hoa = TRUE )
##
summary( metsulfuron.nl, digits = 3 )
##
print( summary( metsulfuron.nl )$cov, digits = 3 )
print( summary( metsulfuron.nl, observed = FALSE )$cov, digits = 3 )Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.