st: Re: Re: plotting fitted lines of percentiles of two variables

["Michael Blasnik" <michael.blasnik@verizon.net>]

Actually, it appears that grqreg does something a little different then what 
you ask for.  It plots the coefficients over a range of quantiles.  It seems 
that you want a plot of fitted values for three different quantiles.  It may 
be better for you to take a direct approach using -predict- to generate the 
fitted values for each quantile and then use a graph command to plot the 
three fitted lines.  Something like:

sqreg infant gdpe, quant(.25 .5 .75)
predict q25hat, equation(q25)
predict q5hat, equation(q50)
predict q75hat, equation(q75)
graph twoway line q25hat q50hat q75hat gdpe

You may want to tweak the graph , especially the legend.

Michael Blasnik

----- Original Message ----- 
From: "Michael Blasnik" <michael.blasnik@verizon.net>
To: <statalist@hsphsun2.harvard.edu>
Sent: Wednesday, August 02, 2006 9:55 AM
Subject: st: Re: plotting fitted lines of percentiles of two variables



> search graph quantile regression, all
>
> will lead you to grqreg, which I think does what you want.  You should try 
> using the search command prior to posting to the list..
>
> Michael Blasnik
>
> ----- Original Message ----- 
> From: "Sam Rawlings, Social Sciences and Law 03" <sr3209@bristol.ac.uk>
> To: <statalist@hsphsun2.harvard.edu>
> Sent: Wednesday, August 02, 2006 9:09 AM
> Subject: st: plotting fitted lines of percentiles of two variables
>
>
>
> > I have two variables - Log Infant Mortality Rate (infant) and Log GDP 
> > (gdpe). I want to plot the relationship between infant and gdpe as three 
> > separate fitted lines, one each for the 25th, 50th and 75th percentiles.
> > I tried using qqplot but I get a single line.
> > I believe what I want is a graphical represention of the results of
> > sqreg infant gdpe, quant(.25 .5 .75).
> >
> > Any help would be much appreciated. Thanks,
> >
> > Samantha
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