

   UUnnb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

        ucv(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 unbiased 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::

        `bcv', `width.SJ', `density'

