gettvc {rmutil} | R Documentation |

`gettvc`

finds the most recent value of a time-varying covariate
before each observed response and possibly adds them to a list of other
time-varying covariates.
It compares the times of response observations with those of
time-varying covariates to find the most recent observed time-varying
covariate for each response. These are either placed in a new object of
class, `tvcov`

, added to an already existing list of matrices containing
other time-varying covariates and a new object of class, `tvcov`

,
created, or added to an existing object of class, `tvcov`

.

If there are response observation times before the first covariate time, the covariate for these times is set to zero.

gettvc(response, times=NULL, tvcov=NULL, tvctimes=NULL, oldtvcov=NULL, ties=TRUE)

`response` |
A list of two column matrices with response values and
times for each individual, one matrix or dataframe of response
values, or an object of class, `response` (created by
`restovec` ). |

`times` |
When `response` is a matrix, a vector of possibly
unequally spaced times for the response, when they are the same for
all individuals or a matrix of times. Not necessary if equally spaced. |

`tvcov` |
A list of two column matrices with time-varying covariate values and corresponding times for each individual or one matrix or dataframe of such covariate values. Times need not be the same as for responses. |

`tvctimes` |
When the time-varying covariate is a matrix, a vector of possibly unequally spaced times for the covariate, when they are the same for all individuals or a matrix of times. Not necessary if equally spaced. |

`oldtvcov` |
A list of matrices with time-varying covariate values,
observed at the event times in `response` , for each individual,
or an object of class, `tvcov` . If not provided, a new object is
created. |

`ties` |
If TRUE, when the response and covariate times are identical, the response depends on that new value (as in observational studies); if FALSE, only the next response depends on that value (for example, if the covariate is a new treatment just applied at that time). |

An object of class, `tvcov`

, is returned containing the new time-varying
covariate and, possibly, those in `oldtvcov`

.

J.K. Lindsey and D.F. Heitjan

`carma`

, `elliptic`

,
`gar`

, `kalcount`

,
`kalseries`

, `kalsurv`

,
`read.list`

, `restovec`

,
`tvctomat`

.

y <- matrix(rnorm(20), ncol=5) resp <- restovec(y, times=c(1,3,6,10,15)) z <- matrix(rpois(20,5),ncol=5) z # create a new time-varying covariate object for the response newtvc <- gettvc(resp, tvcov=z, tvctimes=c(1,2,5,12,14)) covariates(newtvc) # add another time-varying covariate to the object z2 <- matrix(rpois(20,5),ncol=5) z2 newtvc2 <- gettvc(resp, tvcov=z2, tvctimes=c(0,4,5,12,16), oldtvc=newtvc) covariates(newtvc2)

[Package *rmutil* version 1.0 Index]