All Questions
Tagged with nonparametric t-test
96
questions
2
votes
1
answer
5k
views
Paired t-test of a non-normal data with sample size 66
I have a paired data with n=66. I understand that normality condition of differences data should be met to conduct a paired t-test. However, from the histogram, it doesn't appear so normal. The p-...
- 135
7
votes
3
answers
9k
views
Non-parametric alternative to simple t-test
I have five numeric variables of two populations (each of them with 60 individuals) and for each of those five variables I want to know if there is difference in the means.
I was trying to use a ...
1
vote
0
answers
45
views
Non parametric tests for relation/association between variable
What could be an appropriate test for checking whether there exist any relationship between Net Promoter Score ( Categorical in nature with 0 meaning detractor, 1 meaning Neutral, 2 meaning Promter ) ...
- 111
3
votes
1
answer
288
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Is the $t$-test asymptotically nonparametric?
Wikpedia defines "parametric statistics" as:
...a branch of statistics which assumes that sample data comes from a
population that follows a probability distribution based on a fixed
set of ...
- 3,750
1
vote
1
answer
226
views
Should I use non-parametric tests?
I am a teacher working on a simple research with the aim of studying whether the set of lesson designs I created can improve student performance. I have two groups with 15 students each. I divided ...
1
vote
0
answers
690
views
Bayesian Wilcoxon test
I have a pre-post dataset with 2 observations per subject (propotion data -bounded between 0 and 1-).
I have analyzed the data with a classical dependent t-test under the NHST paradigm. However, as ...
- 157
3
votes
0
answers
113
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When can I use a permutation test to see if means of two distributions differ without Type I errors?
I am analyzing psych experiments which generally take the form of a list of outcome measures for the test and control groups, with roughly equal sample sizes, and I would like to compare their means ...
- 193
0
votes
0
answers
163
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"Partial normality" - when to use t-test vs. non-parametric tests
The title is a bit misleading I suppose, so let me explain in detail what I mean.
For the sake of argument, let's say that we have an experiment, where population is divided into two groups and both ...
- 203
1
vote
2
answers
440
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Non parametric one sample test on difference
I have a group which is not normally distributed. I need to check whether the difference between left and right hand within the group is significant. Initially, I calculated the absolute difference (I ...
- 13
1
vote
2
answers
926
views
wilcoxon mann whitney or t-test?
I would like to compare the number of a particular type of disease that is prevalent in men vs women. The number of diseases is interval data (0,1,2,3,etc). Should I use the wilcoxon mann whitney or t-...
- 107
4
votes
1
answer
3k
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How does the Welch correction for the t-test make the test non-parametric?
In an answer to another question it is asserted that the Welch correction to the t-test makes it non-parametric, and this assertion isn't challenged by a frequent contributor with a deep level of ...
- 18.9k
2
votes
0
answers
455
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Effectiveness of exam: did it achieve the goal?
I have a dataset of student scores in an exam. Its structure is as follows:
...
- 121
3
votes
1
answer
2k
views
Non-parametric equivalent of the 1-sample t-test (not paired)
I have a sample of outcomes of my algorithm and would like to test to some degree of confidence if it differs from zero.
I know I can use a 1-sample t-test (as in https://docs.scipy.org/doc/scipy/...
- 213
4
votes
1
answer
915
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How to analyze random variables with non normal distribution
I'm wondering how random variables can be analyzed using parametric methods if the distribution is not normal.
For example if a variable Y is normal distributed but I'm interested only on values Y2 ...
- 1,059
6
votes
1
answer
3k
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What differentiates the wilcoxon test from t test regarding ordinal variables?
I'm wondering what the wilcoxon test differentiates from the t test so it can be used with ordinal variables. In other words why can't we use a t test for ordinal variables but can we use a wilcoxon ...
- 753