

   SSccaatttteerr PPlloott wwiitthh SSmmooootthh CCuurrvvee FFiitttteedd bbyy LLooeessss

        scatter.smooth(x, y, span=2/3, degree=1,
            family=c("symmetric", "gaussian"),
            xlab=deparse(substitute(x)), ylab=deparse(substitute(y)),
            evaluation=50, ...)
        panel.smooth(x, y, span=2/3, degree=1,
            family=c("symmetric", "gaussian"), zero.line=F, evaluation=50, ...)
        loess.smooth(x, y, span=2/3, degree=1,
            family=c("symmetric", "gaussian"), zero.line=F, evaluation=50, ...)

   AArrgguummeennttss::

          x: x coordinates for scatter plot.

          y: y coordinates for scatter plot.

       span: smoothness parameter for `loess'.

     degree: degree of local polynomial used.

     family: if `family="gaussian"' fitting is by least-
             squares, and if `family="symmetric"' a re-descend-
             ing M estimator is used.

       xlab: label for x axis.

       ylab: label for y axis.

   zero.line: logical for plotting a horizontal line at zero -
             used for residual plots.

   evaluation: number of points at which to evaluate the smooth
             curve.

        ...: graphical parameters.

   DDeessccrriippttiioonn::

        Plot (`scatter.smooth') and add a smooth curve computed
        by `loess' to a scatter plot. `loess.smooth' is an aux-
        iliary function used by the other two.

   VVaalluuee::

        None.

   AAuutthhoorr((ss))::

        B.D. Ripley

   SSeeee AAllssoo::

        `loess'

   EExxaammpplleess::

        data(cars)
        attach(cars)
        scatter.smooth(speed, dist)
        detach()

