lambda2df                package:fda                R Documentation

_C_o_n_v_e_r_t _S_m_o_o_t_h_i_n_g _P_a_r_a_m_e_t_e_r _t_o _D_e_g_r_e_e_s _o_f _F_r_e_e_d_o_m

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

     The degree of roughness of an estimated function is controlled by
     a smoothing parameter lambda that directly multiplies the penalty.
     However, it can be difficult to interpret or choose this value,
     and it is often easier to determine the roughness by choosing a
     value that is equivalent of the degrees of freedom used by the
     smoothing procedure. This function converts a multipler lambda
     into a degrees of freedom value.

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

     lambda2df(argvals, basisfd, wtvec=rep(1, n), Lfd=NULL, lambda=0)

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

argvals : Argument values associated with the values to be smoothed. 

basisfd : A basis object. 

  wtvec : A vector of weights for the data to be smoothed. 

    Lfd : Either a nonnegative integer or a linear differential
          operator object. 

 lambda : The smoothing parameter to be converted. 

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

     The conversion requires a one-dimensional optimization and may be
     therefore computationally intensive.

_V_a_l_u_e:

     The equivalent degrees of freedom value.

_N_o_t_e:

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

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

_S_e_e _A_l_s_o:

_E_x_a_m_p_l_e_s:

