crwSimulator {crawl}R Documentation

Construct a posterior simulation object for the CTCRW state vectors

Description

The crwSimulator function uses a fitted model object from crwMLE and a set of prediction times to construct a list from which crwPostIS will draw a sample from either the posterior distribution of the state vectors conditional on fitted parameters or a full posterior draw from an importance sample of the parameters.

Usage

crwSimulator(object.crwFit, predTime=NULL, parIS=1000, df=Inf, scale=1)

Arguments

object.crwFit A model object from crwMLE.
predTime vector of additional prediction times.
parIS Size of the parameter importance sample
df Degrees of freedom for the t approximation to the parameter posterior
scale Scale multiplier for the covariance matrix of the t approximation

Details

The crwSimulator function produces a list and preprocesses the necessary components for repeated track simulation from a fitted CTCRW model from crwMLE. If df=Inf (default) then a multivariate normal distribution is used to approximate the parameter posterior. If object.crwFit was fitted with crwArgoFilter, then the returned list will also include p.out, which is the approximate probability that the observation is an outlier.

Value

List with the following elements:

x Longitude coordinate with NA at prediction times
y Similar to above for latitude
locType Indicates prediction types with a "p" or observation times with an "o"
P1.y Initial state covariance for latitude
P1.x Initial state covariance for longitude
a1.y Initial latitude state
a1.x Initial longitude state
n.errX number of longitude error model parameters
n.errY number of latitude error model parameters
delta vector of time differences
driftMod Logical. indicates random drift model
stopMod Logical. Indicated stop model fitted
stop.mf stop model design matrix
err.mfX Longitude error model design matrix
err.mfY Latitude error model design matrix
mov.mf Movement model design matrix
fixPar Fixed values for parameters in model fitting
Cmat Covaraince matrix for parameter sampling distribution
Lmat Cholesky decomposition of Cmat
par fitted parameter values
N Total number of locations
loglik log likelihood of the fitted model
Time vector of observation times
coord names of coordinate vectors in original data
Time.name Name of the observation times vector in the original data
thetaSampList A list containing a data frame of parameter vectors and their associated probabilities for a resample

Author(s)

Devin S. Johnson

See Also

See northernFurSeal for example.


[Package crawl version 1.1-0 Index]