# tweedie-internal: Tweedie internal function In tweedie: Evaluation of Tweedie Exponential Family Models

 Tweedie internals R Documentation

## Tweedie internal function

### Description

Internal tweedie functions.

### Usage

```	dtweedie.dlogfdphi(y, mu, phi, power)
dtweedie.logl(phi, y, mu, power)
dtweedie.logl.saddle( phi, power, y, mu, eps=0)
dtweedie.logv.bigp( y, phi, power)
dtweedie.logw.smallp(y, phi, power)
dtweedie.interp(grid, nx, np, xix.lo, xix.hi,p.lo, p.hi, power, xix)
dtweedie.jw.smallp(y, phi, power )
dtweedie.kv.bigp(y, phi, power)
dtweedie.series.bigp(power, y, mu, phi)
dtweedie.series.smallp(power, y, mu, phi)
stored.grids(power)
twpdf(p, phi, y, mu, exact, verbose, funvalue, exitstatus, relerr, its )
twcdf(p, phi, y, mu, exact,          funvalue, exitstatus, relerr, its )
```

### Arguments

 `y` the vector of responses `power` the value of power such that the variance is var(Y) = phi * mu^power `mu` the mean `phi` the dispersion `grid` the interpolation grid necessary for the given value of power `nx` the number of interpolation points in the xi dimension `np` the number of interpolation points in the power dimension `xix.lo` the lower value of the transformed xi value used in the interpolation grid. (Note that the value of xi is from 0 to infty, and is transformed such that it is on the range 0 to 1.) `xix.hi` the higher value of the transformed xi value used in the interpolation grid. `p.lo` the lower value of p value used in the interpolation grid. `p.hi` the higher value of p value used in the interpolation grid. `xix` the value of the transformed xi at which a value is sought. `eps` the offset in computing the variance function in the saddlepoint approximation. The default is `eps=1/6` (as suggested by Nelder and Pregibon, 1987). `p` the Tweedie index parameter `exact` a flag for the FORTRAN to use exact-zeros acceleration algorithmic the calculation (1 means to do so) `verbose` a flag for the FORTRAN: 1 means to be verbose `funvalue` the value of the call returned by the FORTRAN code `exitstatus` the exit status returned by the FORTRAN code `relerr` an estimation of the relative error returned by the FORTRAN code `its` the number of iterations of the algorithm returned by the FORTRAN code

### Details

These are not to be called by the user.

### Author(s)

Peter Dunn (pdunn2@usc.edu.au)

### References

Nelder, J. A. and Pregibon, D. (1987). An extended quasi-likelihood function Biometrika, 74(2), 221–232. doi10.1093/biomet/74.2.221

tweedie documentation built on Aug. 17, 2022, 9:06 a.m.