1. 1 Correlation [kor-uh-ley-shun] noun Statistics: the degree to which two or more attributes or measurements show a tendency to vary together. HONR 101 Big Data C. Coullard

2. 2 Correlation is Positive if the values increase together Correlation r = 0.96 > 0

3. 3 Correlation is Negative: Correlation r = - 0.93 < 0 if one set of values decreases when the other set of values increases

4. 4 No Correlation Correlation r = - 0.06

5. 5 Correlation coefficient r The (x i,y i ) pairs with both above mean increase numerator. One above and other below decrease numerator.

6. 6 Correlation coefficient r

7. 7 More examples

8. 8 Does Correlation imply Causation? Do ice cream sales cause the temperature to rise? Do high temperatures cause more ice cream sales?

9. 9 Do absences cause low course grades? Do low course grades cause absences? Does Correlation imply Causation? Does it Matter?

10. 10 Do sunglasses cause ice cream cravings? Does ice cream cause sensitivity to sun? Does Correlation imply Causation? Does it Matter?

11. 11 Does Correlation imply Causation? Do cigarettes cause lung cancer? Does lung cancer cause cigarette craving? Does it Matter?

12. 12 Assignment