rock                  package:boot                  R Documentation

_M_e_a_s_u_r_e_m_e_n_t_s _o_n _P_e_t_r_o_l_e_u_m _R_o_c_k _S_a_m_p_l_e_s

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

     The `rock' data frame has 48 rows and 4 columns.

     Twelve core samples from petroleum reservoirs were sampled by 4
     cross-sections.  Each core sample was measured for permeability,
     and each cross-section has total area of pores, total perimeter of
     pores, and shape.

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

     data(rock)

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

     This data frame contains the following columns:

     `_a_r_e_a' The area of the pores space (in pixels out of 256  x  256).

     `_p_e_r_i' The total perimeter of the pores (in pixels).

     `_s_h_a_p_e' The shape of the pores space defined as `peri/sqrt(area)'.

     `_p_e_r_m' The permeability in milli-Darcies.

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

     The data were collected and kindly made available by R. Katz of
     the Department of Statistics at the University of Oxford.

     Katz, R. (1995) Spatial Analysis of Pore Images. D.Phil. thesis,
     Department of Statistics, University of Oxford.

_R_e_f_e_r_e_n_c_e_s:

     Davison, A.C. and Hinkley, D.V. (1997) Bootstrap Methods and Their
     Application. Cambridge University Press.

     Venables, W.N. and Ripley, B.D. (1994) Modern Applied Statistics
     with S-Plus. Springer-Verlag.

