Wilcoxon signed ranks Test

Question 1

Checklist

Answer 1

Ordinal data
Repeated measures design
Test for difference

Question 2

Calculation steps

Answer 2

1. Calculate differences between Condition A & B (A-B)
2. 0 differences are ignored
3. Differences are ranked (ignore± when ranking)
4. Sum the positive ranks and the negative ranks
5. The smaller of these 2 values is calculated value of T

Question 3

Critical value

Answer 3

Check critical value table based on 1-tailed/2-tailed hypothesis, significance level and N (don’t count 0 differences as part of N)

Question 4

Significance statement

Answer 4

If the calculated T value is less than or equal to the critical T value the result is significant = reject Null Hypothesis.
If the calculated T value is greater than the critical T value the result is not significant = accept Null Hypothesis.