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reReg (version 1.2.1)

simSC: Function to generate simulated data

Description

The function simSC generates simulated recurrent event data from either a Cox-type model, an accelerated mean model, or a scale-change model. The censoring time could be either independent (given covariates) or informative. The simulated data is used for illustration.

Usage

simSC(n, a, b, indCen = TRUE, type = c("cox", "am", "sc"), tau = 60,
  zVar = 0.25, summary = FALSE)

Arguments

n

number of observation.

a

a numeric vector of parameter of length 2.

b

a numeric vector of parameter of length 2.

indCen

a logical value indicating whether the censoring assumption is imposed. When indCen = TRUE, we set \(Z = 1\). Otherwise, \(Z\) is generated from a unit-mean gamma distribution See Details.

type

a character string specifying the underlying model. See Details

tau

a numeric value specifying the maximum observation time.

zVar

a numeric variable specifying the variance of \(Z\). This is only needed when \(indCen\) is TRUE. The default value is 0.25.

summary

a logical value indicating whether a brief data summary will be printed.

Details

The function simSC generates simulated recurrent event data under different scenarios based on the following assumptions. See Details in reReg for a more complete model assumptions.

type = "cox"

generates recurrent event data from a Cox-type model with $$\lambda(t) = Z \lambda_0(t) e^{X^\top a}, h(t) = Zh_0(t)e^{X^\top b}.$$

type = "am"

generates recurrent event data from an accelerated mean model with $$\lambda(t) = Z \lambda_0(te^{X^\top a}) e^{X^\top a}, h(t) = Zh_0(te^{X^\top b})e^{X^\top b}.$$

type = "sc"

generates recurrent event data from a generalized scale-change model with $$\lambda(t) = Z \lambda_0(te^{X^\top a}) e^{X^\top b}, h(t) = Zh_0(te^{X^\top a})e^{X^\top b}.$$

Let \(D\) be the informative failure time with the above hazard function. An non-informative failure time, \(C\), is generated separately from an exponential distribution with mean 80. The observed follow-up time is then taken to be \(min(D, C, \tau)\). We further assume $$\lambda_0(t) = \frac{2}{1 + t}, h_0(t) = \frac{1}{8(1 + t)}.$$ Two covariates are considered; x1 follows a Bernoulli distribution with probability 0.5 and x2 follows a standard normal distribution.

See Also

reReg

Examples

Run this code
# NOT RUN {
set.seed(123)
simSC(200, c(-1, 1), c(-1, 1), summary = TRUE)
# }

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