Non-parametric

Question 1

Assumptions for wilcoxon signed rank test single sample is
Underlying data is symmetrical about the median

Answer 1

No.
Underlying distribution is symmetrical about the median

Question 2

Assumptions for
Wilcoxon signed rank test paired sample is
Distribution of the population of differences is symmetrical about the media.

Answer 2

No.
Distribution of the population of differences is symmetrical about the median DIFFERENCE.

Question 3

Assumptions for
Wilcoxon rank-sum test

Answer 3

Both populations have the same shape of distribution

Question 4

Which gets rank 1, the least or the greatest value?

Answer 4

Wilcoxon signed rank test: least

Wilcoxon rank sum test: doesn’t matter

Question 5

What is m and n?

Answer 5

refers to the sample size in wilcoxon rank sum test
m is the ranks of the data in the smallest sample.
n is the ranks of the data in the biggest sample.

Question 6

Assumptions wilcoxon signed rank test 2 independent samples

Answer 6

Test is not applicable

Question 7

Wilcoxon rank sum test paired sample

Answer 7

Test isn’t applicable

Question 8

Assumptions for sign test

Answer 8

No assumptions

Question 9

Why the wilcoxon signed rank test is preferable than signed test

Answer 9

The magnitude of deviations of the sample values from the population median are taken into consideration apart from just the signs

Question 10

A 2-independent samples is tested using wilcoxon rank sum test. Give a reason that will validate this

Answer 10

The distributions of the two populations are not known to be normal.

Question 11

Describe the circumstances where the following are used:
1. Parametric test
2. Non-parametric test

Answer 11

1. (Distribution of population / underlying distribution) is known
2. (Distribution of population / underlying distribution) is not known

Question 12

It is claimed the median of the population is higher than 5. Therefore, which is correct?
1. H₀: μ=5
2. H₀: median=5

Answer 12

None. The correct answer is
H₀: population median = 5

Question 13

Samples of time taken to run on track A and another samples of time taken to run on track B are collected, and a non-parametric test is to be conducted

Show two correct ways two write null hypothesis
and two wrong ways.

Answer 13

Correct:
1. Population median A = population median B
2. The median time taken to run on track A and the median time taken to run on track B are the same

Wrong:
1. Median A=median B
2. The median of the samples of the time taken to run on track A and the median of the samples of the time taken to run on track B are the same