Wilcoxon tests Flashcards
1
Q
Assumptions of parametric tests
A
the data is normally distributed
It consists of interval level data
Assumes there is a homogeneity of variance
2
Q
Lord on numbers
A
Said that numbers don’t know where they came from. He thought that you could use ordinal data with parametric tests.
3
Q
When would you use the Wilcoxon rank sum test
A
If you have non-parametric data and you have two groups which are independent.
4
Q
When would you use the Wilcoxon signed rank test
A
You would use this test for repeated measures.
It tests the null hypothesis that two related samples were drawn from identical populations with the same mean.
5
Q
Pro’s and cons of non-parametric tests
A
+They don’t rely on parametric assumptions
+They operate on ranks
- Parametric tests are sufficient
- Lower power relative to parametric tests
- Not as good for smaller samples
