PBG package:nlme R Documentation _E_f_f_e_c_t _o_f _P_h_e_n_y_l_b_i_g_u_a_n_i_d_e _o_n _B_l_o_o_d _P_r_e_s_s_u_r_e _D_e_s_c_r_i_p_t_i_o_n: The 'PBG' data frame has 60 rows and 5 columns. _F_o_r_m_a_t: This data frame contains the following columns: _d_e_l_t_a_B_P a numeric vector _d_o_s_e a numeric vector _R_u_n an ordered factor with levels 'T5' < 'T4' < 'T3' < 'T2' < 'T1' < 'P5' < 'P3' < 'P2' < 'P4' < 'P1' _T_r_e_a_t_m_e_n_t a factor with levels 'MDL 72222' 'Placebo' _R_a_b_b_i_t an ordered factor with levels '5' < '3' < '2' < '4' < '1' _D_e_t_a_i_l_s: Data on an experiment to examine the effect of a antagonist MDL 72222 on the change in blood pressure experienced with increasing dosage of phenylbiguanide are described in Ludbrook (1994) and analyzed in Venables and Ripley (1999, section 8.8). Each of five rabbits was exposed to increasing doses of phenylbiguanide after having either a placebo or the HD5-antagonist MDL 72222 administered. _S_o_u_r_c_e: Pinheiro, J. C. and Bates, D. M. (2000), _Mixed-Effects Models in S and S-PLUS_, Springer, New York. (Appendix A.21) Venables, W. N. and Ripley, B. D. (1999) _Modern Applied Statistics with S-PLUS (3rd ed)_, Springer, New York. Ludbrook, J. (1994), Repeated measurements and multiple comparisons in cardiovascular research, _Cardiovascular Research_, *28*, 303-311.