All Questions
7
questions
2
votes
2
answers
337
views
Concept Clarification: Wilcoxon rank test vs two-samples T-test (UPDATE)
I am currently deciding whether to use the Wilcoxon rank test vs two-samples T-test to assess BMI between two unrelated groups. Using the following code to assess normality ...
- 361
0
votes
0
answers
933
views
Normally distributed data but small sample size, use nonparametric test?
My data set is very small (n=16) which according to a Shapiro-wilk test is normally distributed (p=0.82), despite the histogram looking questionable. When I split the data into my two categories there ...
0
votes
1
answer
36
views
Significant difference between two non normal and inhomogene groups
I've done some measurement of tissue rigidity. So I did 1.000 measures with healthy (n=300) and ill (n=700) people.
Now I want to find out if there is a significant different value of the measured ...
- 101
2
votes
2
answers
585
views
Mann Whitney U test with normal distribution approximation: null hypothesis rejected?
I'm new with U test and I have some doubts about the rejection of the null hypothesis with the U test with normal distribution approximation.
In my example I used this data for a 1 tailed test:
$$
...
- 21
2
votes
0
answers
167
views
How do I check data for normality, then what next...?
I am currently undertaking a hypothesis test for some financial returns data. I'm getting slightly confused on parametric versus non-parametric testing. I am testing a market portfolio of 305 stocks ...
- 21
0
votes
2
answers
2k
views
Absolute values -- parametric or non-parametric test?
I am looking at the absolute difference in values between pairs of numbers. I am then comparing these absolute values between two groups (e.g. Males and Females). Since these are absolute values I ...
- 1
4
votes
4
answers
10k
views
Which test to choose when the results from t-test and Wilcoxon test are different?
I have a sample of 48. According to the central limit theorem, I may consider means of every continuous variable in my sample to have a normal distribution.
However, one variable has a mean of 14 +/- ...
- 41