This class of objects is returned by the coxph
class of functions
to represent a fitted hazards model, when the model has
multiple states. The object inherits from the coxph
class.
The object has all the components of a coxph
object, with the
following additions and variations.
a character vector listing the states in the model
the coefficient map. A matrix containing a column for each transition and a row for each coefficient, the value maps that transition/coefficient pair to a position in the coefficient vector. If a particular covariate is not used by a transition the matrix will contain a zero in that position, if two transitions share a coefficient the matrix will contain repeats.
the stratum map. The row labeled `(Baseline)' identifies transitions that do or do not share a baseline hazard. Further rows correspond to strata() terms in the model, each of which may apply to some transitions and not others.
mapping for the residuals and linear predictors. A two column matrix with one row for each element of the vectors and two columns, the first contains the data row and the second the transition.
In a multi-state model a set of intermediate observations is created
during the computation, with a separate set of data rows for each
transition. An observation (id and time interval) that is at risk for
more than one transition will for instance have a linear predictor and
residual for each of the potential transitions. As a result the vector
of linear predictors will be longer than the number of observations.
The rmap
matrix shows the mapping.
coxph
, coxph.object