Bond                package:SASmixed                R Documentation

_S_t_r_e_n_g_t_h_s _o_f _m_e_t_a_l _b_o_n_d_s

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

     The 'Bond' data frame has 21 rows and 3 columns of data on the
     strength required to break metal bonds according to the metal and
     the ingot.

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

     This data frame contains the following columns:

     _p_r_e_s_s_u_r_e a numeric vector of pressures required to break the bond

     _M_e_t_a_l a factor with levels 'c', 'i' and 'n' indicating the metal
          involved (copper, iron or nickel).

     _I_n_g_o_t an ordered factor indicating the ingot of the composition
          material.

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

     Littel, R. C., Milliken, G. A., Stroup, W. W., and Wolfinger, R.
     D. (1996), _SAS System for Mixed Models_, SAS Institute (Data Set
     1.2.4).

     Mendenhall, M., Wackerly, D. D. and Schaeffer, R. L. (1990),
     _Mathematical Statistics_, Wadsworth (Exercise 13.36).

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

     str(Bond)
     options(contrasts = c(unordered = "contr.SAS", ordered = "contr.poly"))
     if (require("lme4", quietly = TRUE, character = TRUE)) {
       ## compare with output 1.1 on p. 6
       print(fm1Bond <- lmer(pressure ~ Metal + (1|Ingot), Bond))
       print(anova(fm1Bond))
     }

