topic Re: ANOVA TEST in New SAS User

ANOVA TEST

ccavaco — Thu, 12 Oct 2023 20:44:19 GMT

I am currently trying to work on a problem that looks at performing a oneway ANOVA test, testing the three drugs’ effects on SBP (systolic blood pressure). What
is the overall p-value for the test? Using the Tukey (default) method of multiple
comparisons, what do you conclude about the three drug levels (Placebo, Drug A,
and Drug B)?

Re: ANOVA TEST

ccavaco — Thu, 12 Oct 2023 20:47:28 GMT

But I can not find the appropriate p-value

Re: ANOVA TEST

Reeza — Thu, 12 Oct 2023 20:49:36 GMT

Show your output and indicate how you cannot find the p-value? Does that mean you do not get results or that you do not know where in the output to obtain the p-value?

Re: ANOVA TEST

PaigeMiller — Fri, 13 Oct 2023 08:04:59 GMT

You don't show us your code, but I will assume that you are doing this Tukey test in PROC GLM. Next time show us your code, don't make me guess or assume.

In the MEANS statement, Tukey's multiple comparison generally does not produce p-values. It produces pairwise comparisons via the LINES option, which produces results like this:

You can also get the confidence intervals for pairwise comparison of means using the CLDIFF option, but again no p-values.

In the LSMEANS statement, with the PDIFF option, you can get p-values

Re: ANOVA TEST

sbxkoenk — Thu, 12 Oct 2023 22:04:18 GMT

Not sure if this tutorial talks about Tukey, but I still thought I would post it :

SAS Tutorial | What is ANOVA?
https://www.youtube.com/watch?v=C1s0ZXNTheo

by my colleague @AndyRavenna

Koen