prefilter
generates initial values for model parameters and unobserved states;
structures data and initial values for C++ TMB
template;
fits state-space model; minimizes the joint log-likelihood via the selected
optimizer (nlminb
or optim
); structures and passes output
object to fit_ssm
sfilter(
x,
model = c("rw", "crw"),
time.step = 6,
scale = FALSE,
parameters = NULL,
map = NULL,
fit.to.subset = TRUE,
control = ssm_control(),
inner.control = NULL
)
Argos data passed through prefilter()
specify which SSM is to be fit: "rw" or "crw"
the regular time interval, in hours, to predict to. Alternatively, a vector of prediction times, possibly not regular, must be specified as a data.frame with id and POSIXt dates.
scale location data for more efficient optimization.
a list of initial values for all model parameters and unobserved states, default is to let sfilter specify these. Only play with this if you know what you are doing...
a named list of parameters as factors that are to be fixed during estimation, e.g., list(psi = factor(NA))
fit the SSM to the data subset determined by prefilter (default is TRUE)
list of control parameters for the outer optimization (see ssm_control
for details)
list of control settings for the inner optimization (see ?TMB::MakeADFUN for additional details)
called by fit_ssm
, not intended for general use. sfilter
can only fit to an
individual track, use fit_ssm
to fit to multiple tracks (see ?fit_ssm).