1. Spearman’s Rank Correlation Coefficient
To see if a correlation is statistically significant

3. The Spearman’s rank test gives you a number between -1 and 1.
-1 = a perfect negative correlation
1 = a perfect positive correlation
0 = no correlation
The graph in the middle will have a value close to -1

4. Difference between an observation’s ranking for the two variables you are investigating
It will make sense
In a minute
Spearman’s rank correlation coefficient
Number of observations

5. Is there a correlation between height and weight of a person?
H0 – There is no correlation between height and weight of a person

6. Data Collected

7. The shortest height so gets a rank of 1
The heaviest weight gets a rank of 10
These two people weigh the same. If you get a tie, average the rankings between the two. They are both 4th and 5th so they both get 4.5

8. Add up the values of d2
= 50.5

10. Number of observations
0.694
What does this tell you about the correlation? (Larger than or equal to, you can reject the null)
Number of observations
The critical value is 0.648

11. 0.694 is greater than 0.648
....so the correlation is significant at the 0.05 level
We can reject our null hypothesis!!!!!!

12. Is there a significant correlation between height and hand area?

13. Person
Height
Height ranking
Hand area
Hand area ranking d d2 1 2 3 4 5 6 7 8 9 10 11 12 13 14