summary.nlreg {nlreg} | R Documentation |
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 nlreg object. This is assumed to be the result of
some fit that produces an object inheriting from the class
nlreg , in the sense that the components returned by the
nlreg function will be available.
|
observed |
logical argument. If TRUE , the observed information is
used to calculate the covariance matrix, the expected information
otherwise. The default is TRUE .
|
correlation |
logical argument. If TRUE , the correlation matrix for the
parameter estimates is computed; default is TRUE .
|
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 nlreg object, but
with the arguments all named.
|
digits |
then number of significant digits to be printed. |
ws |
the ws component of the nlreg object.
|
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 )