All Questions
10
questions
0
votes
0
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229
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How to interpret results from the data if Levene's test is violated?
I'm doing ANCOVA analysis. So, the assumption of Levene's test is violated which means I have to run a non-parametric test. Does that mean I can't interpret other results that I obtained from the data ...
- 1
3
votes
2
answers
180
views
How to handle assumptions of statistical tests?
Does any definitive work exist, e.g. a review, a book chapter, or a book, on the advantages and disadvantages of existing approaches? Is there a consensus on which approach is the right one?
I have ...
- 199
20
votes
3
answers
3k
views
When to check model assumptions
Statistical methods are based on model assumptions. For example, an independent one-way ANOVA makes the following assumptions:
Normally distributed residuals
Homogeneity of variance
Independence of ...
- 301
3
votes
1
answer
279
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Do non-parametric tests depend on homoscedastic data?
I am finding myself having to perform non-parametric tests, primarily Mann-Whitney tests, on datasets which are not normally distributed.
I notice that the datasets are not homoscedastic - do these ...
- 43
7
votes
3
answers
9k
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Can I use the Mann-Whitney U test sequentially (pairwise) when I have three groups or do I need to use the Kruskal-Wallis test?
My question has three parts (the method and results for my experiment follow the questions):
If I have three groups of non-parametric sample data, can I use the Mann-Whitney U test to test the Null ...
- 213
1
vote
0
answers
35
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How can one verify distributional assumptions for testing procedures, if only one draw from each distribution is available
I am currently dealing with a situation in which the Wilcoxon signed rank test (WSRT) is a possible candidate to be applied to the data. So let`s say we have $n$ pairs of Random Variables $(X_i, Y_i)$ ...
- 3,104
2
votes
1
answer
1k
views
Assumptions of the Friedman Rank Test
Let $X_i:= (X_{i,1}, ..., X_{i,k}) $ for $i =1...n$ be $\mathbb{R}^k$-valued random Variables with $k\geq2$.
I wonder what the exact assumptions are to apply the Friedman test to Realisations of ...
- 3,104
1
vote
0
answers
66
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Non-parametric hypothesis test - to account for violations of regression model
I am performing a multiple linear regression with response, Y and independent variables X1, X2 and intercept term.
The regression coefficients indicate statistically significant prediction of both X1 ...
- 53
9
votes
2
answers
201
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How do you verify test assumptions in real world cases, without testing them
We know that, formally, the assumptions of a test cannot be tested, because if we choose what test to use based on the results of the test, the resulting composite test has unknown properties (Type I ...
- 18.3k
2
votes
0
answers
435
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What is the nonparametric variant of multivariate ANOVA with more than one one factor (and with interactions between factors)? [duplicate]
I analyze real data where assuptions of classical multiway (more than one factor assumed) MANOVA (more than one response variable) are not met (normality, equal variances). Is there any nonparametric ...
- 3,989