RE: OT: t-tests, non-parametric tests, and large studies—a paradox of statistical practice?

Posted by Rich Ulrich on Jan 11, 2013; 7:41pm
URL: http://spssx-discussion.165.s1.nabble.com/OT-t-tests-non-parametric-tests-and-large-studies-a-paradox-of-statistical-practice-tp5717324p5717331.html

[re-posted; first try seems to have failed.]
Oh, thanks!  That looks important. 

I have disliked the rank-based tests for the simpler reasons, for a
long time.  I would not have guessed that large Ns made them
so strong as tests against  "shape"  instead of location. 

 - I wonder, though, if Fagerland told the whole story, about the increased
use of non-parametric tests in studies with large Ns.  Since there are
some people who are (overly) concerned with non-normality, I did
eventually become willing to do my t-tests and report them in detail,
while tossing in the assurance that non-parametric tests showed the
same conclusions.  By nominal tabulation, my use increased over time. 
You would have to separate out that sort of back-up confirmation before
you conclude that there is really a lot of cherry-picking of results for their
p-values.

--
Rich Ulrich

> Date: Thu, 10 Jan 2013 12:56:11 -0800

> From: [hidden email]
> Subject: OT: t-tests, non-parametric tests, and large studies—a paradox of statistical practice?
> To: [hidden email]
>
> Here's an (open access) article you may find interesting.
>
> http://www.biomedcentral.com/1471-2288/12/78
>
> Cheers,
> Bruce
> ...