R: Developer documentation: transition model structure object

qmodel.object {msm} | R Documentation

## Developer documentation: transition model structure object

### Description

A list giving information about the structure of states and allowed transitions in a multi-state model, and options for likelihood calculation. Used in internal computations, and returned in a fitted `msm` model object.

### Value

`nstates` | Number of states
`iso` | Label for which basic structure the model is isomorphic to in the list of structures for which analytic formulae for the transition probabilities are implemented in the source file `src/analyticp.c`. This list is given by the internal object `msm:::.msm.graphs` which is defined and documented in the source file `R/constants.R`. `iso` is 0 if the analytic P matrix is not implemented for this structure, or if analytic P matrix calculations are disabled using `use.analyticp=FALSE` in the call to `msm`.
`perm` | Permutation required to convert the base isomorphism into the structure of this model. A vector of integers whose rth element is the state number in the base structure representing state r in the current structure.
`qperm` | Inverse permutation: vector whose rth element is the state number in the current structure representing the rth state in the base structure.
`npars` | Number of allowed instantaneous transitions, equal to `sum(imatrix)`.
`imatrix` | Indicator matrix for allowed instantaneous transitions. This has (r,s) entry 1 if the transition from r to s is permitted in continuous time, and 0 otherwise. The diagonal entries are arbitrarily set to 0.
`qmatrix` | Matrix of initial values for the transition intensities, supplied as the `qmatrix` argument of `msm`.
`inits` | Vector of these initial values, reading across rows of `qmatrix` and excluding the diagonal and disallowed transitions.
`constr` | Indicators for equality constraints on baseline intensities, taken from the `qconstraint` argument to `msm`, and mapped if necessary to the set (1,2,3,...).
`ndpars` | Number of distinct allowed instantaneous transitions, after applying equality constraints.
`expm` | Use expm package to calculate matrix exponentials for likelihoods, as supplied to the `use.expm` argument of `msm`. `TRUE` or `FALSE`.

### See Also

`msm.object`,`emodel.object`, `hmodel.object`.

[Package msm version 1.6.7 Index]