Then, follow up your t test with a statement of the effect size and its
associated confidence interval.
---Jerry Zar
>>> dennis roberts <[EMAIL PROTECTED]> 04/07 2:46 pm >>>
i was not suggesting taking away from our arsenal of tricks ... but,
since
i was one of those old guys too ... i am wondering if we were mostly
lead
astray ...?
the more i work with statistical methods, the less i see any meaningful
(at
the level of dominance that we see it) applications of hypothesis
testing ...
here is a typical problem ... and we teach students this!
1. we design a new treatment
2. we do an experiment
3. our null hypothesis is that both 'methods', new and old, produce the
same results
4. we WANT to reject the null (especially if OUR method is better!)
5. we DO a two sample t test (our t was 2.98 with 60 df) and reject the
null ... and in our favor!
6. what has this told us?
if this is ALL you do ... what it has told you AT BEST is that ... the
methods probably are not the same ... but, is that the question of
interest
to us?
no ... the real question is: how much difference is there in the two
methods?
our t test does NOT say anything about that
===========================================================================
This list is open to everyone. Occasionally, less thoughtful
people send inappropriate messages. Please DO NOT COMPLAIN TO
THE POSTMASTER about these messages because the postmaster has no
way of controlling them, and excessive complaints will result in
termination of the list.
For information about this list, including information about the
problem of inappropriate messages and information about how to
unsubscribe, please see the web page at
http://jse.stat.ncsu.edu/
===========================================================================
