All Questions
11
questions
3
votes
1
answer
211
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Kruskal-Wallis returns only one significant group (out of 4 groups), when significant group is removed and test redone, another group is significant?
I am comparing 4 groups of samples using SPSS. The groups are 4 bathymetry groups (>0m, >-1m, >-2m, >-3m). Within each group are a number of samples n. Each sample has a recorded seagrass ...
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1
vote
1
answer
1k
views
How to do pairwise comparisons for Kruskal Wallis test?
If the null hypothesis in the Kruskal Wallis test is rejected, How can we perform pairwise comparisons? Can we apply Dunnett's Test for that?
- 11
1
vote
1
answer
2k
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How do I interpret the p-value in a Dunn-test?
I conducted a Kruskal Wallis test for my sample sizes, and this is what I got:
Kruskal-Wallis chi-squared = 12.138, df = 4, p-value = 0.01635
The p-value is below 0.05, so I know there is a ...
- 15
4
votes
2
answers
2k
views
Which pairwise comparison tests are best to use after the Kruskal-Wallis test (Dunn, Conover-Iman or Steel-Dwass-Critchlow-Fligner test)?
I have 3 sampling sites where I took 3 water samples in each site. I chose to do the Kruskal-Wallis test to find out if there is a significant difference in total nitrogen between the sites. I did not ...
2
votes
1
answer
2k
views
Is Dunn-Sidak approach in MATLAB multcompare identical to so-called Dunn's test?
I've asked the same question elsewhere.
These two articles recommend Dunn's test as non-parametric post hoc multiple comparison test following Kruskal-Wallis test.
How the Dunn method for ...
0
votes
0
answers
147
views
Kruskal Wallis test gives significance, multiple comparision table doesn't
I'm comparing physico-chemical properties of 8 different kefir samples like viscosity at different storage times. I have 4 viscosity measurements for each group. When I conduct Kruskal Wallis test; ...
- 1
4
votes
0
answers
238
views
multiple Kruskal-Wallis instead of ANOVA for non-normally distributed data
Apologies in advanced if I supply too little or vague information, since I am a complete newbie in stats and using this forum.
So I did a study which evaluated psychopathic personality traits, ...
- 41
0
votes
0
answers
398
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Kruskal-Wallis post hoc comparisons different results in different software used
I'm having some trouble analyzing my data because when I use StatSoft Statistica and run a Kruskal-Wallis, I get one set of values for multiple comparisons, but when the same analysis is run in XLSTAT ...
- 81
5
votes
2
answers
5k
views
Any other non-parametric alternative to Kruskal-Wallis?
It looks like Kruskal-Wallis is the standard nonparametric test for more than two groups. The problem is that it does not tell which groups are different, except that whether there exists significant ...
- 185
12
votes
1
answer
10k
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Multiple comparisons in a non-parametric test
I am working with a data set that is non-parametric and has 12 treatments. I performed the Kruskal-Wallis test and got a significant $p$-value, and now I would like to conduct a multiple comparisons ...
- 121
8
votes
1
answer
13k
views
Differences between Dwass-Steel-Critchlow-Fligner and Mann-Whitney U-test for a post-hoc pairwise analysis
If you have one control and four groups of patients with a non-normal small sample size, there are differences in these tests for a post-hoc analysis after Kruskal-Wallis?
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