Re: st: Concord - plottting problem

[Nick Cox <njcoxstata@gmail.com>]

That behaviour is wired into the code at present, although it could be changed.

I suppose showing the entire range could be justified as a feature
allowing  consistent comparison, but I have absolutely no recall of
whether that's my code or Thomas Steichen's or of whether it was
deliberate or an oversight. (-concord-'s first public appearance was
1998.) TJS = Thomas J. Steichen, twice retired, NJC = Nicholas J. Cox,
still responsible for this child.

There's a work-around.

levelsof site, local(sites)

foreach s of local sites {
        preserve
        keep if site == `s'
        concord <whatever>
        restore
}

A completely different comment is that with values like those given,
ranging from about 14 to 370, multiplicative comparisons may be in
order, i.e. compare ln(x1) and ln(x2) as well.


Nick
njcoxstata@gmail.com


On 7 May 2013 07:36, Martyn Sherriff <statams48@gmail.com> wrote:
> I am using concord (package concord from
> http://fmwww.bc.edu/repec/bocode/c, 3.1.0 10nov2010  TJS & NJC
> graphics improvements ) to look at agreement. I have several sites to
> look at, so I stacked the data as x1, x2 and site as a variable to
> select the data. When I use the plotting options of 'loa' and 'qnormd'
> selecting on the value of site the plots are satisfactory. However
> when I use the option 'ccc', the one that I am interested in, the axes
> take the maximum values of the entire dataset ignoring the 'if'
> condition. I have tried to limit the axes to no avail:
>
> concord x1 x2 if site == 1,loa
> results in an x-axis upper limit of 100, whereas
> concord x1 x2 if site == 1,ccc
> results in an x-axis upper limit of 400
>
> The summary data is:
> . tabstat x1 x2,stats(n min max) by(site)
>
> Summary statistics: N, min, max
>   by categories of: site
>
>     site |        x1        x2
> ---------+--------------------
>        1 |        13        13
>          |     13.82     13.82
>          |     98.36      98.4
> ---------+--------------------
>        2 |        17        17
>          |     37.77     38.25
>          |       360       369
> ---------+--------------------
>    Total |        30        30
>          |     13.82     13.82
>          |       360       369
> ------------------------------
>
> I realise that I am missing something quite simple in the syntax but I
> just cannot see it.
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