NLSstAsymptotic            package:stats            R Documentation

_F_i_t _t_h_e _A_s_y_m_p_t_o_t_i_c _R_e_g_r_e_s_s_i_o_n _M_o_d_e_l

_D_e_s_c_r_i_p_t_i_o_n:

     Fits the asymptotic regression model, in the form 'b0 +
     b1*(1-exp(-exp(lrc) * x)' to the 'xy' data.   This can be used as
     a building block in determining starting estimates for more
     complicated models.

_U_s_a_g_e:

     NLSstAsymptotic(xy)

_A_r_g_u_m_e_n_t_s:

      xy: a 'sortedXyData' object

_V_a_l_u_e:

     A numeric value of length 3 with components labelled 'b0', 'b1',
     and 'lrc'.  'b0' is the estimated intercept on the 'y'-axis, 'b1'
     is the estimated difference between the asymptote and the
     'y'-intercept, and 'lrc' is the estimated logarithm of the rate
     constant.

_A_u_t_h_o_r(_s):

     Jose Pinheiro and Douglas Bates

_S_e_e _A_l_s_o:

     'SSasymp'

_E_x_a_m_p_l_e_s:

     data( Loblolly )
     Lob.329 <- Loblolly[ Loblolly$Seed == "329", ]
     NLSstAsymptotic(sortedXyData(expression(age), expression(height), Lob.329 ))

