On 13 Feb 2002 09:48:41 -0800, [EMAIL PROTECTED] (Dennis Roberts) wrote:
At 09:21 AM 2/13/02 -0600, Mike Granaas wrote:
On Fri, 8 Feb 2002, Thomas Souers wrote:
2) Secondly, are contrasts used primarily as planned comparisons? If
so, why?
I would second those who've already
On Fri, 8 Feb 2002, Thomas Souers wrote:
2) Secondly, are contrasts used primarily as planned comparisons? If so, why?
I would second those who've already indicated that planned comparisons are
superior in answering theoretical questions and add a couple of comments:
1) an omnibus test
Thomas Souers wrote:
Hello, I have two questions regarding multiple comparison tests for a one-way ANOVA
(fixed effects model).
1) Consider the Protected LSD test, where we first use the F statistic to test the
hypothesis of equality of factor level means. Here we have a type I error rate
At 09:21 AM 2/13/02 -0600, Mike Granaas wrote:
On Fri, 8 Feb 2002, Thomas Souers wrote:
2) Secondly, are contrasts used primarily as planned comparisons? If
so, why?
I would second those who've already indicated that planned comparisons are
superior in answering theoretical questions and
Hello, I have two questions regarding multiple comparison tests for a one-way ANOVA
(fixed effects model).
1) Consider the Protected LSD test, where we first use the F statistic to test the
hypothesis of equality of factor level means. Here we have a type I error rate of
alpha. If the global
You have to keep in mind that the LSD is concerned with familywise error
rate, which is the probability that you will make at least one
type I error in your set of conclusions. For the familywise error rate, 3
errors are no worse than 1.
Suppose that you have three groups. If the omnibus null is
At 10:37 AM 2/8/02 -0800, Thomas Souers wrote:
2) Secondly, are contrasts used primarily as planned comparisons? If so, why?
well, in the typical rather complex study ... all pairs of possible mean
differences (as one example) are NOT equally important to the testing of
your theory or notions
Hi
On 8 Feb 2002, Thomas Souers wrote:
2) Secondly, are contrasts used primarily as planned
comparisons? If so, why?
There are a great many possible contrasts even with a relatively
small number of means. If you examine the data and then decide
what contrasts to do, then you have in some
