

   LLooggiitt ooff PPrrooppoorrttiioonnss

        logit(p)

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

          p: A numeric Splus object, all of whose values are in
             the range [0,1].  Missing values (`NA's) are
             allowed.

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

        This function calculates the logit of proportions.

   DDeettaaiillss::

        If any elements of `p' are outside the unit interval
        then an error message is generated.  Values of `p'
        equal to 0 or 1 (to within machine precision) will
        return `-Inf' or `Inf' respectively.  Any `NA's in the
        input will also be `NA's in the output.

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

        A numeric object of the same type as `p' containing the
        logits of the input values.

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

        `inv.logit'

