[rkward-devel] power analysis plugin

[Thomas Friedrichsmeier]

Hi,

On Wednesday 08 October 2014 11:49:56 meik michalke wrote:
> > - For GLM, would it make sense to allow to specify "number of parameters
> > to
> > estimate", and "sample size (N)", instead of numerator / denominator df?
> 
> i went for the wording used by ?pwr.f2.test, but i admit it sounds a bit
> scary ;-)

thinking about it, there is one scenario, where my idea won't work, namely 
when estimating the number of "estimatable" parameters (or numerator df). In 
this case there is no trivial mapping from sample size to denominator df.

Well, a small reminder on the relation between parameter count, number of 
observations, and df, in the help file will come in handy...
 
> > - That said, I wonder, whether the following printout would be good enough
> > 
> > (after the rk.header()):
> >    rk.print.literal (capture.output (print (x)))
> > 
> > (we could add a new function "rk.print.simple(x)" for this kind of output.
> > It would probably make sense in other places, too).
> 
> to me it looks a bit more consistent with the RKWard output you're used to
> now. it partly emulates what print.power.htest() does, but with rk.*
> functions. for copy&paste scenarios, i'd prefer that table.

True, that would be somewhat inconsistent. But actually for some plugins, I'm 
not entirely satisfied with the output generated by rk.print()/HTML(). Esp. 
print lm estimation results. So that's where the idea came from. But we'll 
leave it for now.
 
> btw, if you have text for the help file, i would like to try to put it in
> the rkwarddev script, to test a new possibility to generate .rkh files i
> implemented just yesterday.

Not much. I started, then stumbled across those issues, then got side-tracked. 
This is all I got so far:

## Documentation
pwr.rkh.summary <- rk.rkh.summary ("Perform power anaylsis for a variety of 
statistcal methods.")
pwr.rkh.usage <- rk.rkh.usage ("Given three of the parameters 'power of test', 
'sample size', 'effect size', and 'significance level', this plugin will 
estimate the fourth, i.e. for example the test power of a t.test at a given 
sample size, effect size, and level of significance. On the left hand control, 
select which of the parameters to estimate. In the middle, specify the 
statistical method, on the right hand side, enter the values of the given 
parameters.")
pwr.rkh.settings <- rk.rkh.settings (
  rk.rkh.setting (pwr.parameter.rad, text="Parameter to estimate, given the 
others."),
  rk.rkh.setting (pwr.parameter.towsamples.rad, text="Only shown when 
applicable: For estimating the required sample sizes for a test with two 
differently sized samples, specify which should be estimated, and which is 
given.")
)

> it stores text for elements by ID in an
> environement, and when rk.plugin.component() or rk.plugin.skeleton() use
> the "scan" option for "setting" nodes, that text is automatically filled
> in. to get the text into the environment, you can now provide it with the
> same functions which generates the XML element, e.g.
> 
>  rk.set.comp("Example component")
>  rk.XML.cbox(
>    label="Cherry",
>    value="cherry",
>    help="Check this to get a cherry on top.")
> 
> without rk.set.comp() you'd have to 'add component="Example component"' to
> the rk.XML.cbox() call, which is a bit annoying after the third time... to
> see the stored text, run
> 
>  rk.get.rkh.prompter()

Not pretending, I understood this, completely, but sounds good. Will try when 
I have a bit of time (not today).

Regards
Thomas
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 198 bytes
Desc: This is a digitally signed message part.
URL: <http://mail.kde.org/pipermail/rkward-devel/attachments/20141008/f1a4fb54/attachment.sig>