R: Stochastic Process Model for Analysis of Longitudinal and...
stpm
R Documentation
Stochastic Process Model for Analysis of Longitudinal and Time-to-Event Outcomes
Description
Utilities to estimate parameters of the models with survival functions induced by
stochastic covariates. Miscellaneous functions for data preparation and simulation
are also provided. For more information, see: "Stochastic model for analysis of
longitudinal data on aging and mortality" by Yashin A. et al, 2007, Mathematical
Biosciences, 208(2), 538-551 <DOI:10.1016/j.mbs.2006.11.006>.
Author(s)
I. Y. Zhbannikov, I. V. Akushevich, K. G. Arbeev, A. I. Yashin.
References
Yashin, A. et al (2007), Stochastic model for analysis of longitudinal data on aging
and mortality. Mathematical Biosciences, 208(2), 538-551.
Akushevich I., Kulminski A. and Manton K. (2005). Life tables with covariates: Dynamic model
for Nonlinear Analysis of Longitudinal Data. Mathematical Popu-lation Studies, 12(2), pp.: 51-80.
<DOI: 10.1080/08898480590932296>.
Yashin, A. et al (2007), Health decline, aging and mortality: how are they related?
Biogerontology, 8(3), 291-302.<DOI:10.1007/s10522-006-9073-3>.
Examples
## Not run:
library(stpm)
#Prepare data for optimization
data <- prepare_data(x=system.file("data","longdat.csv",package="stpm"),
y=system.file("data","vitstat.csv",package="stpm"))
#Parameters estimation (default model: discrete-time):
p.discr.model <- spm(data)
p.discr.model
# Continuous-time model:
p.cont.model <- spm(data, model="continuous")
p.cont.model
#Model with time-dependent coefficients:
data <- prepare_data(x=system.file("data","longdat.csv",package="stpm"),
y=system.file("data","vitstat.csv",package="stpm"),
covariates="BMI")
p.td.model <- spm(data, model="time-dependent")
p.td.model
## End(Not run)