In article <94o81d$9o4$[EMAIL PROTECTED]>,
Elliot Cramer <[EMAIL PROTECTED]> wrote:
> Dale Berger <[EMAIL PROTECTED]> wrote:
> : Dear Colleagues,
>
> : A student is evaluating a summer program for junior high students.
One of
> : the goals was to raise 'self esteem.' Measures were taken before
the
>
> there is no good answer. You might look at "problems in measuring
> change" edited by chester Harris. He should have done a randomized
> experiment and he could then have gotten a definite answer.
>
> You might look at the deviations from the regression of post and pre
and
> see if this relates to anything
>
Someone pointed out the book by DT Campbell and DA Kenny (1999) A primer
on regression artifacts. The Guilford Press. I ordered it, and it has
been a pleasure to read.
Chapter 6 in Campbell & Kenny (1999) discuss the various ways of
correcting for regression to the mean in pre- and post-test comparisons.
They present 3 different ways for correcting for the regression to the
mean effect: residualized change, "backward" residualized change, and
estimated true change. They provide an example which produces
qualitatively different answers for each method. Each method can be
justified based on the meaning of "change."
I can't reproduce their arguments here. Campbell & Kenny provide
detailed equations with extensive citations of the primary literature
and reviews. They conclude that the measurement of change has been and
continues to be a highly controversial subject.
--
Eugene D. Gallagher
ECOS, UMASS/Boston
Sent via Deja.com
http://www.deja.com/
=================================================================
Instructions for joining and leaving this list and remarks about
the problem of INAPPROPRIATE MESSAGES are available at
http://jse.stat.ncsu.edu/
=================================================================
