

   MMeeaassuurreemmeennttss oonn PPeettrroolleeuumm RRoocckk SSaammpplleess

   AArrgguummeennttss::

       area: The area of the pores space (in pixels out of 256
             x  256).

       peri: The total perimeter of the pores (in pixels).

      shape: The shape of the pores space defined as
             `peri/sqrt(area)'.

       perm: The permeability in milli-Darcies.

   SSUUMMMMAARRYY::

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

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

   DDAATTAA DDEESSCCRRIIPPTTIIOONN::

        This data frame contains the following columns:

   SSOOUURRCCE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.

   OOTTHHEERR RREEFFEERREENNCCEESS::

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

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

