dtweedie-internal          package:tweedie          R Documentation

_T_w_e_e_d_i_e _i_n_t_e_r_n_a_l _f_u_n_c_t_i_o_n

_D_e_s_c_r_i_p_t_i_o_n:

     Internal tweedie functions.

_U_s_a_g_e:

     dtweedie.dldphi( phi, mu, power, y)
     dtweedie.dldphi.saddle( y, mu, phi, power)
     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)
     tweedie.dev(y, mu, power)
     stored.grids(power)

_A_r_g_u_m_e_n_t_s:

       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).

_D_e_t_a_i_l_s:

     These are not to be called by the user.

_A_u_t_h_o_r(_s):

     Peter Dunn (dunn@usq.edu.au)

_R_e_f_e_r_e_n_c_e_s:

     Nelder, J. A. and Pregibon, D. (1987). An extended
     quasi-likelihood function _Biometrika_, *74*(2), 221-232.

