A researcher finds a correlation of minus 0.8 between hours of exercise and resting heart rate. Which is the correct interpretation?
Answer and explanation
Correct answer: D. A strong negative association that does not prove causation
- Step 1: The sign shows direction and the magnitude shows strength.
- Step 2: A value of minus 0.8 means higher exercise goes with lower heart rate, but confounding is possible.
Answer
A strong negative association that does not prove causation.
Why not the others: No relationship exists: A value near zero would show no linear relationship. Exercise causes a lower heart rate in every individual: Correlation does not prove causation or apply to every individual. A weak positive association: 0.8 is strong, and the sign is negative.
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