estSDE: Bayesian estimation in mixed stochastic differential...

Description Usage Arguments Details Value References Examples

Description

Bayesian estimation of the random effects φ_j in the mixed SDE dY_i(t)= b(φ_i, t, Y_i(t))dt + γ s(t, Y_i(t)) dW_i(t), , φ_i~N(μ, Ω), i=1,...,n and the parameters μ, Ω, γ^2.

Usage

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estSDE(t, y, prior, start, bSDE, sVar, ipred = 1, cut, len = 1000,
  Omega = "diag", mod = c("Gompertz", "logistic", "Weibull", "Richards",
  "Paris", "Paris2"), modVar = "", propPar = 0.02)

Arguments

t

vector of observation times

y

matrix or list of the n trajectories

prior

list of prior parameters - list(m, v, priorOmega, alpha, beta), priorOmega=list(alpha, beta) if Omega="diag", otherwise prior matrix of Wishart distribution

start

list of starting values

bSDE

b(phi, t, x) drift function

sVar

variance function s^2

ipred

which of the n trajectories is the one to be predicted

cut

the index how many of the ipred-th series are used for estimation

len

number of iterations of the MCMC algorithm - chain length

Omega

structure of the variance matrix Omega of the random effects, diagonal matrix, otherwise inverse wishart distributed

mod

model out of Gompertz, Richards, logistic, Weibull, Paris, Paris2, only used instead of bSDE

modVar

default value is sVar(t,x)=1, if "AR": sVar(t,x)=x

propPar

proposal standard deviation of phi is |start$mu|*propPar

Details

Simulation from the posterior distribution of the random effect from n independent trajectories of the SDE (the Brownian motions W1,...,Wn are independent).

?

Value

phi

samples from posterior of φ

mu

samples from posterior of μ

Omega

samples from posterior of Ω

gamma2

samples from posterior of γ^2

References

Hermann et al. (2015)

Examples

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mod <- "Gompertz"
bSDE <- getFun("SDE", mod)
mu <- getPar("SDE", mod, "truePar")
n <- 5
parameters <- defaultPar(mu, n)
y <- drawData("SDE", bSDE, parameters)
t <- parameters$t

prior <- getPrior(mu, parameters$gamma2)
start <- getStart(mu, n)
chains <- estSDE(t, y, prior, start, bSDE)

SimoneHermann/hierRegSDE documentation built on May 9, 2019, 1:46 p.m.