recovery              package:multcomp              R Documentation

_R_e_c_o_v_e_r_y _T_i_m_e _D_a_t_a _S_e_t

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

     Recovery time after surgery.

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

     data("recovery")

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

     This data frame contains the following variables

     _b_l_a_n_k_e_t blanket type, a factor at four levels: 'b0', 'b1', 'b2',
          and 'b3'.

     _m_i_n_u_t_e_s response variable: recovery time after a surgical 
          procedure.

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

     A company developed specialized heating blankets designed to help
     the body heat following a surgical procedure. Four types of
     blankets were tried on surgical patients with the aim of comparing
     the recovery time of patients. One of the blanket was a standard
     blanket that had been in use already in various hospitals.

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

     P. H. Westfall, R. D. Tobias, D. Rom, R. D. Wolfinger, Y. Hochberg
     (1999). _Multiple Comparisons and Multiple Tests Using the SAS
     System_. Cary, NC: SAS Institute Inc., page 66.

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

       ### set up one-way ANOVA
       amod <- aov(minutes ~ blanket, data = recovery)

       ### set up multiple comparisons: one-sided Dunnett contrasts
       rht <- glht(amod, linfct = mcp(blanket = "Dunnett"), 
                   alternative = "less")

       ### cf. Westfall et al. (1999, p. 80)
       confint(rht, level = 0.9)

       ### the same
       rht <- glht(amod, linfct = mcp(blanket = c("b1 - b0 >= 0", 
                                                  "b2 - b0 >= 0", 
                                                  "b3 - b0 >= 0")))
       confint(rht, level = 0.9)

