RE: st: * mark indicating between group significans in box plots

[Nick Cox <n.j.cox@durham.ac.uk>]

Thanks. 

If this was a ladder, I would refuse to climb it. 

More seriously, "ladder plot" is another name for a plot given many other names. 

Recently Edward Tufte has been pushing them hard on www.edwardtufte.com as "slopegraphs". 

Yet more names are gathered together in 

SJ-9-4  gr0041  . . . . . . Speaking Stata: Paired, parallel, or profile plots
        . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  N. J. Cox
        Q4/09   SJ 9(4):621--639                                 (no commands)
        explores paired, parallel, and profile plot making for
        changes, correlations, and other comparisons between
        variables

which was also referred to yesterday in the same thread. 

Nick 
n.j.cox@durham.ac.uk 

Seed, Paul

As Lars has paired data, he might want to consider 
a ladder plot.  This will show the linkage between 
his observations, on which his test is based.

************* example program *************
clear
sysuse auto
gen id = _n
rename turn t1
rename trunk t2
keep t1 t2 id
reshape long t, i(id) j(number)
twoway (connected t number ,  text(1.5 50 "an interesting graph") )
************* end example *************

And no, I don't think Nick was rude. I have similar discussions 
all the time.  It no doubt depends on discipline, and Lars 
does not give us a context to understand what he is trying to do, 
but in medicine and now in biomedical science there has been 
an increasing emphasis on estimating the size of effects, 
with confidence intervals and exact p-values; and 
away from mere "yes/no" thinking of the kind encouraged by stars. 

Den 10/11/11 13.19 skrev "Nick Cox" <n.j.cox@durham.ac.uk>:

>I don't think anyone would have thought you rude here. Me, possibly....
>
>Here is an oblique answer.
>
>sysuse auto
>graph box turn trunk, text(55 50 "an interesting graph") ysc(r(. 60))
>
>Nick 
>n.j.cox@durham.ac.uk
>
>Lars Folkestad
>
>It seems that some of my text has disappeared here.
>
>Im using a: Wilcoxon signed ranks test - as my data is paired and not
>normally distributed.
>
>I did not mean to be rude.
>
>I respect your decision not to answer, but seeing that this the starring
>is a much used and
>Often asked for by reviewers in my field I hope someone who knows the
>answer to how to star mark
>A boxplot will answer.
>
>Den 10/11/11 12.50 skrev "Nick Cox" <njcoxstata@gmail.com>:
>
>>I will show my hand, as it were.
>>
>>I've often seen people test a difference between means and show a box
>>plot as the graphical equivalent. I'd argue that a plot of means with
>>confidence intervals would be directly related, although even then
>>there are pitfalls.
>>
>>Of  course, that may not be what you are doing. If your test were say
>>a Mann-Whitney-Wilcoxon test, a box plot makes more sense.
>>
>>Even so, a -dotplot- or -stripplot- (SSC) shows much detail than a box
>>plot for two groups. A -qqplot- is even better.
>>
>>I personally dislike starring as a primitive practice and draw the
>>line at explaining how to do it but there are plenty of people to
>>think otherwise.
>
>Den 10/11/11 10.31 skrev "Lars Folkestad" <lfolkestad@health.sdu.dk>:
>
>>>>Sorry, thought it was a graphics question and did thus not mention the
>>>>statistics
>
>Den 10/11/11 10.05 skrev "Nick Cox" <njcoxstata@gmail.com>:
>
>>>>>Various thoughts, but I'll mention only one: What's the underlying
>>>>>test?
>
>On Thu, Nov 10, 2011 at 8:49 AM, Lars Folkestad
>
>>>>>> Im trying to indicate between group significant in a box plot using
>>>>>>
>>>>>>
>>>>>>        . graph box y1 y2
>>>>>>
>>>>>> Now i want to indicate that the between y1 and y2 there is a between
>>>>>>group
>>>>>> significants using the standard * for p<0.05 and ** for p<0.001
>>>>>> I can do it in the editor, but if there is a code i could put in my
>>>>>>do
>>>>>> file, that would be the easiest.
>>>>>>
>>>>>> Iv been fiddling with the yvar option in something like this:
>>>>>>
>>>>>> . graph box y1 y2, box(1, lcolor(navy) yvar(re("*")) box(2,
>>>>>>fcolor(green)
>>>>>> lcolor(green))


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