

   CCDD44 CCoouunnttss ffoorr HHIIVV--PPoossiittiivvee PPaattiieennttss

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

   baseline: The CD4 counts (in 100's) on admission to the
             trial.

    oneyear: The CD4 counts (in 100's) after one year of treat-
             ment with the new drug.

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

        The `cd4' data frame has 20 rows and 2 columns.

        CD4 cells are carried in the blood as part of the human
        immune system.  One of the effects of the HIV virus is
        that these cells die.  The count of CD4 cells is used
        in determining the onset of full-blown AIDS in a
        patient.  In this study of the effectiveness of a new
        anti-viral drug on HIV, 20 HIV-positive patients had
        their CD4 counts recorded and then were put on a course
        of treatment with this drug.  After using the drug for
        one year, their CD4 counts were again recorded.  The
        aim of the experiment was to show that patients taking
        the drug had increased CD4 counts which is not gener-
        ally seen in HIV-positive patients.

   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 obtained from

        DiCiccio, T.J. and Efron  B. (1996) Bootstrap confi-
        dence intervals (with Discussion). Statistical Science,
        11, 189-228.

   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.

