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surveillance (version 1.5-4)

hhh4_methods: Print, Summary and Extraction Methods for "ah4" Objects

Description

Besides print and summary methods there are also some standard extraction methods defined for objects of class "ah4" resulting from a call to hhh4.

Usage

## S3 method for class 'ah4':
print(x, digits = max(3, getOption("digits") - 3),
       reparamPsi = TRUE, ...)
## S3 method for class 'ah4':
summary(object, ...)

## S3 method for class 'ah4': coef(object, se = FALSE, reparamPsi = TRUE, idx2Exp = NULL, amplitudeShift = FALSE, ...) ## S3 method for class 'ah4': fixef(object, ...) ## S3 method for class 'ah4': ranef(object, tomatrix = FALSE, ...)

## S3 method for class 'ah4': AIC(object, ..., k = 2) ## S3 method for class 'ah4': logLik(object, ...)

## S3 method for class 'ah4': confint(object, parm, level = 0.95, reparamPsi = TRUE, idx2Exp = NULL, amplitudeShift = FALSE, ...)

Arguments

x, object
an object of class "ah4".
digits
the number of significant digits to use when printing
reparamPsi
logical. If TRUE, the overdispersion parameter from the negative binomial distribution is transformed from internal (log-)scale to a user scale (where zero corresponds to a Poisson distribution).
...
For the summary, fixef and ranef methods: arguments passed to coef. For the remaining methods: unused (argument of the generic).
se
logical switch indicating if standard errors are required
idx2Exp
vector with integers idicating the parameters which should be returned on exp-scale.
amplitudeShift
logical switch indicating whether the parameters for sine/cosine terms modelling seasonal patterns (see addSeason2formula) should be transformed to an amplitude/shift formulation.
tomatrix
logical. If FALSE (default), the vector of all random effects is returned (as used internally). However, for random intercepts of type="car", the number of parameters is one less than the number of regions and the ind
k
numeric specifying the the penalty per parameter to be used; k = 2 is the classical AIC.
parm
a vector of numbers or names, specifying which parameters are to be given confidence intervals. If missing, all parameters are considered.
level
the confidence level required.

Value

encoding

latin1

Details

The function coef returns all estimated (regression) parameters from a model as propsed by Paul and Held (2011), see hhh4. If the model includes random effects, those can be extracted with ranef, whereas fixef returns the fixed parameters.

The function AIC returns the value of the AIC criterion only for models without random effects, and returns NULL in the case of a random effects model where AIC is problematic.

The function logLik returns an object of class "logLik" in the case of a model without random effects, and the value of the penalized log-likelihood at the parameter estimates otherwise.

The function confint returns Wald-type confidence intervals (assuming asymptotic normality) for one or more parameters in the fitted model.

References

Paul, M. and Held, L. (2011) Predictive assessment of a non-linear random effects model for multivariate time series of infectious disease counts. Statistics in Medicine, 30, 1118--1136.