quawak                package:lmomco                R Documentation

_Q_u_a_n_t_i_l_e _F_u_n_c_t_i_o_n _o_f _t_h_e _W_a_k_e_b_y _D_i_s_t_r_i_b_u_t_i_o_n

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

     This function computes the quantiles of the Wakeby distribution
     given parameters (xi, alpha, beta, gamma, and delta) of the
     distribution computed by 'parwak'. The quantile function of the
     distribution is


 x(F) = xi+frac{alpha}{beta}(1-(1-F)^beta)- frac{gamma}{delta}(1-(1-F))^{-delta} mbox{,}


     where x(F) is the quantile for nonexceedance probability F, xi is
     a location parameter, alpha and beta are scale parameters, and
     gamma, and delta are shape parameters. The five returned
     parameters from 'parwak' in order are xi, alpha, beta, gamma, and
     delta.

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

     quawak(f, wakpara)

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

       f: Nonexceedance probability (0 <= F <= 1).

 wakpara: The parameters from 'parwak' or similar.

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

     Quantile value for nonexceedance probability F.

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

     W.H. Asquith

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

     Hosking, J.R.M., 1990, L-moments-Analysis and estimation of
     distributions using linear combinations of order statistics:
     Journal of the Royal Statistical Society, Series B, vol. 52, p.
     105-124.

     Hosking, J.R.M., 1996, FORTRAN routines for use with the method of
     L-moments: Version 3, IBM Research Report RC20525, T.J. Watson
     Research Center, Yorktown Heights, New York.

     Hosking, J.R.M. and Wallis, J.R., 1997, Regional frequency
     analysis-An approach based on L-moments: Cambridge University
     Press.

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

     'cdfwak', 'parwak'

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

       lmr <- lmom.ub(c(123,34,4,654,37,78))
       quawak(0.5,parwak(lmr))

