MAX                   package:drc                   R Documentation

_M_a_x_i_m_u_m _m_e_a_n _r_e_s_p_o_n_s_e

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

     'MAX' estimates the maximum mean response and the dose at which it
     occurs.

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

     MAX(object, lower = 1e-3, upper = 1000, pool = TRUE)

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

  object: an object of class 'drc'.

   lower: numeric. Lower limit for bisection method. Need to be smaller
          than EDx level to be calculated.

   upper: numeric. Upper limit for bisection method. Need to be larger
          than EDx level to be calculated.

    pool: logical. If TRUE curves are pooled. Otherwise they are not.
          This argument only works for models with independently fitted
          curves as specified in 'drm'.

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

     This function is only implemented for the built-in functions of
     class 'braincousens' and  'cedergreen'.

     This function was used for obtaining the results on hormesis
     effect size reported in Cedergreen et al. (2005).

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

     A matrix with one row per curve in the data set and two columns: 
     one containing the dose at which the maximum occurs  and one
     containing the corresponding maximum response.

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

     Christian Ritz

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

     Cedergreen, N. and Ritz, C. and Streibig, J. C. (2005) Improved
     empirical models describing hormesis,  _Environmental Toxicology
     and Chemistry_ *24*, 3166-3172.

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

     ## Fitting a Cedergreen-Ritz-Streibig model
     lettuce.m1 <- drm(weight~conc, data = lettuce, fct = CRS.4c())

     ## Finding maximum average response and the corrresponding dose
     MAX(lettuce.m1)

