fix.family.link             package:mgcv             R Documentation

_M_o_d_i_f_y _f_a_m_i_l_i_e_s _f_o_r _u_s_e _i_n _G_A_M _f_i_t_t_i_n_g

_D_e_s_c_r_i_p_t_i_o_n:

     Generalized Additive Model fitting by `outer' iteration, requires
     extra derivatives of the variance and link functions to be  added
     to family objects. The functions add what is needed.

_U_s_a_g_e:

     fix.family.link(fam)
     fix.family.var(fam)

_A_r_g_u_m_e_n_t_s:

     fam: A 'family'.

_D_e_t_a_i_l_s:

     Outer iteration GAM estimation requires derivatives of the
     GCV/UBRE score, which are obtained by differentiating the P-IRLS
     GAM fitting iteration w.r.t. the model smoothing parameters. The
     expressions for the derivatives require the second derivative of
     the link w.r.t. the mean, and the first derivative of the variance
     function w.r.t. the mean. These functions add functions evaluating
     these quantities to a family.

_V_a_l_u_e:

     A family object with extra component functions 'dvar' and
     'd2link'.

_A_u_t_h_o_r(_s):

     Simon N. Wood simon.wood@r-project.org

