Oxide                  package:nlme                  R Documentation

_V_a_r_i_a_b_i_l_i_t_y _i_n _S_e_m_i_c_o_n_d_u_c_t_o_r _M_a_n_u_f_a_c_t_u_r_i_n_g

_D_e_s_c_r_i_p_t_i_o_n:

     The 'Oxide' data frame has 72 rows and 5 columns.

_F_o_r_m_a_t:

     This data frame contains the following columns:

     _S_o_u_r_c_e a factor with levels '1' and '2' 

     _L_o_t a factor giving a unique identifier for each lot.

     _W_a_f_e_r a factor giving a unique identifier for each wafer within a
          lot.

     _S_i_t_e a factor with levels '1',  '2', and  '3' 

     _T_h_i_c_k_n_e_s_s a numeric vector giving the thickness of the oxide
          layer.

_D_e_t_a_i_l_s:

     These data are described in Littell et al. (1996, p. 155) as
     coming ``from a passive data collection study in the semiconductor
     industry where the objective is to estimate the variance
     components to determine the assignable causes of the observed
     variability.'' The observed response is the thickness of the oxide
     layer on silicon wafers, measured at three different sites of each
     of three wafers selected from each of eight lots sampled from the
     population of lots.

_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.20)

     Littell, R. C., Milliken, G. A., Stroup, W. W. and Wolfinger, R.
     D. (1996), _SAS System for Mixed Models_, SAS Institute, Cary, NC.

_E_x_a_m_p_l_e_s:

     data(Oxide)

