All Questions
Tagged with parametric nonparametric
15
questions
2
votes
4
answers
469
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I want to show by simulation that the Wilcoxon test is more robust than the Student test for non-normally distributed data
I want to test by simulation that the Wilcoxon test is more robust than the Student test for non-normally distributed data.
For example, I'm testing the ...
- 909
0
votes
0
answers
25
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Parametric or non parametric mixed effect models for very small sample size in ecological/soil data?
I am running an ecological/environmental experiment in a salt marsh with 5 experimental treatments and 3 replicate soil samples taken from each treatment. I have been taking measurements from these ...
- 1
1
vote
2
answers
163
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Parametric vs Non-parametric test recommendation
What type of non-parametric test would be suitable for the dataset shown in the image:
The sample size is 200 each for both variables. The data value can vary from 0-4 for both variables. The ...
- 13
3
votes
1
answer
131
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If I have a very small n for one group and a very large number of features, should I choose a parametric or a non-parametric test?
I have a dataset that contains human metabolite concetration in a fluid. One group has about 12 samples, while another only has 5. My question is if I can assume normality for this data and do ANOVA/t-...
2
votes
0
answers
24
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Is there a statistical test for five groups with averages ONLY?
The data I collected was measuring plant shoot masses and these were extremely small, so I could only find the total mass of the shoots from 30 plants. Hence, I only have the mean and none of the ...
user387381
2
votes
1
answer
127
views
Fisher Z transformation still not normal
I have 18 different groups that I need to compare. I used the raw values from a neuroimaging file to represent synchronization between two brain regions (which ranged from 0 to 1) and Fisher Z ...
- 21
0
votes
1
answer
57
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Importance of normality testing in clinical trials / AB tests
I’m curious to read about the importance of normality testing in AB tests and clinical trials.
It seems that there is a lot of mixed (and strong) opinions about the necessity for normality testing, ...
- 67
0
votes
0
answers
396
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Use of both parametric and non-parametric tests in the same study
Suppose we are investigating whether there is a significant difference in dependent variables A and B between two treatments in a population. Let's assume that the data provide parametric assumptions (...
- 41
3
votes
2
answers
180
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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
2
votes
1
answer
741
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Is Kernel-Regression parametric or non-parametric?
As the title says, is kernel regression a parametric or non-parametric method, and how can this be motivated/explained?
- 35
-1
votes
1
answer
185
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Independent Sample T-test or Mann-Whitney U test?
I am a very young stats learner, and I need help understanding the justification of a test choice. I have a sample of 39 participants (20 females and 19 males) been measured on task performance, and I ...
- 1
19
votes
3
answers
5k
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Why are parametric tests more powerful than non-parametric tests?
I'd like to understand why parametric tests are more powerful than their non-parametric alternatives. Is the word choice of "power" the same as statistical power? As I understand it, power ...
- 1,653
1
vote
1
answer
92
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Survey sampling: How many participants per group (current, former, and potential users) should we recruit?
We are designing research in which we will explore the perception of users (C current, F former, and P potential) on a product. We apply the same questionnaire for each group adapting (verb tenses) ...
0
votes
0
answers
45
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What repeated measures statistical tests should I use with uneven sample size and parametrical/nonparametrical distribution?
I'm looking for a way to measure significance + variance homogeneity/heterogenity
First of all I tested my data for normality and it's not always parametrical, so I think that I should use different ...
2
votes
3
answers
479
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When is a hypothesis test appropriate? [closed]
For example, when would a hypothesis test bed used?
- 51