An object of class stateprobs returned by sim_stateprobs() or from
$sim_stateprobs() methods in model classes.
A stateprobs object inherits from data.table and contains
the following columns:
A random sample from the PSA.
The treatment strategy ID.
The patient ID.
The subgroup ID.
The health state ID.
The time at which a state probability is computed.
The probability of being in a given health state.
When simulating individual-level models, the patient_id column is
not included as state probabilities are computed by averaging across patients.
In cohort models, the object also contains size and absorbing attributes.
The size attribute is a numeric vector with the elements n_samples,
n_strategies, n_patients, n_states, and
n_times denoting the number of samples, treatment strategies, patients,
health states, and times. The absorbing attribute is a numeric vector
containing the absorbing health states (see the absorbing field of the
CohortDtstmTrans class for more details).