R: A data projection with previously estimated or user-defined...
spm_projection
R Documentation
A data projection with previously estimated or user-defined parameters.
Projections are constructed for a cohort with fixed or
normally distributed initial covariates.
Description
A data projection with previously estimated or user-defined parameters.
Projections are constructed for a cohort with fixed or
normally distributed initial covariates.
A list of parameters from output of the spm(...) function.
N
A number of individuals to simulate, N=100 by default.
ystart
A vector of starting values of covariates (variables), ystart=80 by default.
model
A model type. Choices are: "discrete", "continuous" or "time-dependent".
tstart
Start time (age), default=30. Can be an interval: c(a, b) - in this case,
the starting time is sumulated via runif(1, a, b).
tend
End time (age), default=105.
dt
A time interval between observations, dt=1 by default.
sd0
A standard deviation value for simulation of the next value of variable.
sd0=1 by default.
nobs
A number of observations (lines) for i-th individual.
gomp
A flag (FALSE by default).
When it is set, then time-dependent exponential form of mu0 and Q are used:
mu0 = mu0*exp(theta*t), Q = Q*exp(theta*t).
Only for continous-time SPM.
Value
An object of 'spm.projection' class with two elements.
(1) A simulated data set.
(2) A summary statistics which includes (i) age-specific means of state variables and
(ii) Survival probabilities.
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>.