Calculates a frequency table counting the number of times each pair of
states were observed in successive observation times. This can be a useful
way of summarising multi-state data.
Usage
statetable.msm(state, subject, data = NULL)
Value
A frequency table with starting states as rows and finishing states
as columns.
Arguments
state
Observed states, assumed to be ordered by time within each
subject.
subject
Subject identification numbers corresponding to state.
If not given, all observations are assumed to be on the same subject.
data
An optional data frame in which the variables represented by
subject and state can be found.
If the data are intermittently observed (panel data) this table should not
be used to decide what transitions should be allowed in the \(Q\) matrix,
which works in continuous time. This function counts the transitions
between states over a time interval, not in real time. There can be
observed transitions between state \(r\) and \(s\) over an interval even
if \(q_{rs}=0\), because the process may have passed through one or more
intermediate states in the middle of the interval.