CItran.fun: Confidence intervals for \(\lambda(t)\) based on transformation
Description
Given the \(\hat \beta\) covariance matrix (or its estimation), an approximate
confidence interval for each \(\lambda(t)=\exp(\nu(t))\) is calculated using a transformation of
the confidence interval for the linear
predictor \(\nu(t)=\textbf{X(t)} \beta\). The transformation is \(\exp(I_i)\),
where \(I_i\) are the confidence limits of \(\nu(t)\).
Numeric vector of the lower values of the intervals.
UIlambda
Numeric vector of the upper values of the intervals.
lambdafit
Input argument.
Arguments
VARbeta
(Estimated) Coariance matrix of the \(\hat \beta\) parameter vector.
lambdafit
Numeric vector of fitted values of the PP intensity
\(\hat \lambda(t)\).
covariates
Matrix of covariates to estimate the PP intensity.
clevel
Confidence level of the confidence intervals. A value in the interval
(0,1).
References
Casella, G. and Berger, R.L., (2002). Statistical inference. Brooks/Cole.
Cebrian, A.C., Abaurrea, J. and Asin, J. (2015). NHPoisson: An R Package for
Fitting and Validating Nonhomogeneous Poisson Processes.
Journal of Statistical Software, 64(6), 1-24.