

   BBiiaasseedd CCrroossss--VVaalliiddaattiioonn ffoorr BBaannddwwiiddtthh SSeelleeccttiioonn

        bcv(x, nb=1000, lower, upper)

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

          x: a numeric vector

         nb: number of bins to use.

     lower,: Range over which to minimize.  The default is
             almost always satisfactory.

   DDeessccrriippttiioonn::

        Uses biased cross-validation to select the bandwidth of
        a  Gaussian kernel density estimator.

   VVaalluuee::

        a bandwidth

   RReeffeerreenncceess::

        Scott, D. W. (1992) Multivariate Density Estimation:
        Theory, Practice, and Visualization.  Wiley.

   SSeeee AAllssoo::

        `ucv', `width.SJ', `density'

