turn on suggestions

Auto-suggest helps you quickly narrow down your search results by suggesting possible matches as you type.

Showing results for

Find a Community

- Home
- /
- Analytics
- /
- Stat Procs
- /
- Kruskal-wallis test significant at p = 0.003 and D...

Topic Options

- Subscribe to RSS Feed
- Mark Topic as New
- Mark Topic as Read
- Float this Topic for Current User
- Bookmark
- Subscribe
- Printer Friendly Page

- Mark as New
- Bookmark
- Subscribe
- Subscribe to RSS Feed
- Highlight
- Email to a Friend
- Report Inappropriate Content

06-17-2016 04:23 PM

A friend of mine asked me if I knew why a kruskall-wallis test of scores had significant p value of 0.003 and the Dunns test showed no statistical significant results.

One person told us to look at quartiles to see the difference. Is it ok to do that? An why Dunns test would not show where were the differences?

Thanks so much.

Maria

Accepted Solutions

Solution

09-20-2016
09:49 PM

- Mark as New
- Bookmark
- Subscribe
- Subscribe to RSS Feed
- Highlight
- Email to a Friend
- Report Inappropriate Content

08-30-2016 08:09 PM

i just notice I forgot to thank you Steve, sorry. Thanks so much!

All Replies

- Mark as New
- Bookmark
- Subscribe
- Subscribe to RSS Feed
- Highlight
- Email to a Friend
- Report Inappropriate Content

06-28-2016 09:02 AM

In Dunn's test, one group is designated as a 'Control' group, and each of the other groups are compared nonparametrically, with an adjustment for the number of comparisons. The K-W is an overall test, that at least one group differs from the others in location.

So you have two things that could cause what you see. The first is that the differences in location may not involve the control group. The second is that the adjustment for multiple comparisons is such that a 'raw' p value may be significant, but after controlling for the number of comparisons, the adjusted p value is not significant.

Steve Denham

Solution

09-20-2016
09:49 PM

- Mark as New
- Bookmark
- Subscribe
- Subscribe to RSS Feed
- Highlight
- Email to a Friend
- Report Inappropriate Content

08-30-2016 08:09 PM

i just notice I forgot to thank you Steve, sorry. Thanks so much!