help aaplot 
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Scatter plot with linear and/or quadratic fit, automatically annotated


Syntax

        aaplot yvar xvar [if] [in] [, quadratic both lopts(lfitoptions)
                  qopts(qfitoptions) aformat(format) bformat(format)
                  cformat(format) rsqformat(format) rmseformat(format)
                  abbrev(#) backdrop(addplot_option) addplot(addplot_option)
                  scatter_options ]


Description

    aaplot graphs a scatter plot for yvar versus xvar with linear and/or
    quadratic fit superimposed.  The equation(s) and R-square statistics of
    the fits shown are also shown at the top of the graph. If just one fit is
    shown, the subtitle is used. The sample size and RMSE(s) are shown in a
    note.


Remarks

    aaplot is indicative, not definitive. Some tastes might run to showing
    (for example) standard errors, t statistics and P-values instead of, or
    in addition to, the results shown.  Users so inclined should feel free to
    clone aaplot and should feel compelled to use their own different program
    name.


Options

    quadratic specifies plotting of quadratic fit only.

    both specifies plotting of linear and quadratic fit. The equation and
        R-square for the quadratic fit are displayed in the subtitle and
        those for the linear fit in the t1title.

    lopts() are options of twoway lfit to tune the rendering of the linear
        fit.

    qopts() are options of twoway qfit to tune the rendering of the quadratic
        fit.

    aformat(), bformat(), cformat(), rsqformat() and rmseformat() tune the
        display format of the constant, the coefficient of the linear term,
        the coefficient of the quadratic term (if any), the R-square
        statistic (given as a percent) and the RMSE.  The defaults are,
        respectively, %7.0g, %7.0g, %7.0g, %3.1f and the display format of
        yvar.  See help on format for guidance.

    abbrev() tunes the abbreviation of longer variable names. By default such
        names are abbreviated in the subtitle using abbrev(, 10). Users may
        change the length shown from 10.

    backdrop(addplot_option) provides a way to add other plots to the
        generated graph, but as backdrop plotted before and below all other
        plots. For example, many users like to draw shaded areas showing
        confidence intervals, but showing all data points too.  See 
        addplot_option.

    addplot(addplot_option) provides a way to add other plots to the
        generated graph.  See addplot_option.

    scatter_options are any options allowed for scatter excluding by().
        These include the options for titling the graph (see title_options),
        for tuning the display of data points and for saving the graph to
        disk (see saving_option).


Examples 

    . sysuse auto, clear
    . gen gpm = 1000 / mpg
    . label var gpm "Gallons per thousand miles"
    . aaplot gpm weight, name(g1)
    . aaplot gpm weight, lopts(lc(blue)) aformat(%04.3f) bformat(%06.5f)
        rmseformat(%4.3f) name(g2)
    . aaplot gpm weight, quadratic qopts(lc(pink)) name(g3)
    . aaplot gpm weight, both name(g4)
    . aaplot gpm weight, both backdrop(lfitci gpm weight, color(gs12))
        name(g5)


Author 

    Nicholas J. Cox, Durham University
    n.j.cox@durham.ac.uk


Acknowledgments

    This problem was suggested by Alona Armstrong.  Kit Baum, Eric Booth and
    Ariel Linden made helpful suggestions.


Also see

    Manual:  [R] regress postestimation, [G] graph twoway