Question

The table below lists the scores of eight research participants on a test to measure anxiety, as well as the typical number of cigarettes each person smokes daily. Scores on the anxiety test can range anywhere from a low of 0 (indicating very low anxiety) to a high of 30 (indicating very high anxiety).
Research

Anxiety

Cigarettes





Participant

Test Score





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1

8

11



2

9

3



3

15

11



4

14

16



5

21

26



6

12

10



7

22

24



8

17

18



Construct a scatterplot to represent the correlation between smoking and anxiety. Describe the direction of the correlation and give two possible explanations for it.

Answer 1

Explanation:

By graphing cigarettes per day on one axis, and anxiety test score on the other axis, we see a strong positive correlation between the two.

One explanation is that smoking causes anxiety.  Another explanation is that people with more anxiety are more likely to smoke.