algae                  package:drc                  R Documentation

_V_o_l_u_m_e _o_f _a_l_g_a_e _a_s _f_u_n_c_t_i_o_n _o_f _i_n_c_r_e_a_s_i_n_g _c_o_n_c_e_n_t_r_a_t_i_o_n_s _o_f _a _h_e_r_b_i_c_i_d_e

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

     Dataset from an experiment exploring the effect of increasing
     concentrations of a herbicide on  the volume of the treated algae.

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

     data(algae)

_F_o_r_m_a_t:

     A data frame with 14 observations on the following 2 variables.

     '_c_o_n_c' a numeric vector of concentrations.

     '_v_o_l' a numeric vector of response values, that is relative change
          in volume.

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

     This datasets requires a cubic root transformation in order to
     stabilise the variance.

_S_o_u_r_c_e:

     Meister, R. and van den Brink, P. (2000) _The Analysis of
     Laboratory Toxicity Experiments_,   Chapter 4 in _Statistics in
     Ecotoxicology_, Editor: T. Sparks,  New York: John Wiley & Sons,
     (pp. 114-116).

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

     algae.m1 <- drm(vol~conc, data=algae, fct=LL.3())
     summary(algae.m1)

     algae.m2 <- boxcox(algae.m1)
     summary(algae.m2)

