R: Diggle-Rowlingson Raised Incidence Model

tribble {splancs} | R Documentation

## Diggle-Rowlingson Raised Incidence Model

### Description

Fits the Diggle-Rowlingson Raised Incidence Model.

### Usage

    tribble(ccflag, vars=NULL, alphas=NULL, betas=NULL, rho,
     which=1:length(alphas), covars=NULL, thetas=NULL,
     steps=NULL, reqmin=0.001, icount=50, hessian=NULL)

### Arguments

`ccflag` | Case-control flag : a vector of ones and zeroes.
`vars` | A matrix where `vars[i,j]` is the distance squared from point `i` to source `j`.
`alphas` | Initial value of the `alpha` parameters.
`betas` | Initial value of the `beta` parameters.
`rho` | Initial value of the `rho` parameter.
`which` | Defines the mapping from sources to parameters.
`covars` | A matrix of covariates to be modelled as log-linear terms. The element `covars[i,j]` is the value of covariate `j` for case/control `i`.
`thetas` | Initial values of covariate parameters.
`steps` | Step sizes for the Nelder-Mead simplex algorithm.
`reqmin` | Tolerance for simplex algorithm
`icount` | Iteration count for simplex algorithm
`hessian` | by default NULL, any other value causes hessian to be computed and returned

### Value

The return value is a list with many components, and class `ribfit`.

`alphas` | A vector of the alpha parameters at the maximum
`betas` | A vector of the beta values at the maximum
`rho` | The value of rho at the maximum
`logl` | The maximised log-likelihood
`null.logl` | The null log-likelihood
`call` | The function call to `tribble`

For further information see Diggle and Rowlingson (1993).

### References

Rowlingson, B. and Diggle, P. 1993 Splancs: spatial point pattern analysis code in S-Plus. Computers and Geosciences, 19, 627-655; the original sources can be accessed at: http://www.maths.lancs.ac.uk/~rowlings/Splancs/. See also Bivand, R. and Gebhardt, A. 2000 Implementing functions for spatial statistical analysis using the R language. Journal of Geographical Systems, 2, 307-317.

### See Also

`triblik`, `dsquare`

[Package splancs version 2.01-40 Index]