Bookmark and Share

Notice: On March 31, it was announced that Statalist is moving from an email list to a forum. The old list will shut down on April 23, and its replacement, is already up and running.

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

RE: st: Non-normal alternative to MANOVA

From   "Nick Cox" <>
To   <>
Subject   RE: st: Non-normal alternative to MANOVA
Date   Mon, 5 Jul 2010 12:27:20 +0100

This is a frequently asked question without an official FAQ. (It's not
StataCorp house style to say "No, we don't do it" unless there is also
an explanation of why it is a very bad idea.) 

See, for example,

and several replies. 


Thanks for the replies.
I've had a look at transforming the data or using lnskew0, the problem
is there
are 15 variables, each measured at 3 times periods (baseline, 7 weeks
and 3
mothns after treatment) and it's pretty difficult to find a
transformation that
works for all of them. The data were skewed at baseline and it only got
after treatment. The confounder numint (number of interventions) is a
issue so I can't ignore it. With 3 repeated measurements I wasn't sure
if you
could use lnskew0 separately on all 3 of them if I'm interested in
changes from

I'll have a look at ranking the data - is there a good reference
anywhere on how
to do that? I did it once in the past but can't remember the details.

> I have been asked to analyse a small dataset from a randomized
> with 24 subjects (12 in each group, control and intervention). There
are 3
> of continuous outcome measures (b1, b2, b3) taken at baseline, 7 weeks
and 3
> months, and 2 variables  which need to be controlled for  - level of
> impair (binary) and number of interventions numint (continuous
> If the data were normal I would have done something like this:
> manova b1 b2 b3=group impair numint, continuous(numint)
> and then do various manova tests.
> Unfortunately the outcome data b1-3 are highly skewed, so I can't use
> What would be a good alternative?

*   For searches and help try:

© Copyright 1996–2015 StataCorp LP   |   Terms of use   |   Privacy   |   Contact us   |   Site index