Professor Johnston has found a strong positive correlation between wearing neckties and the frequency of strokes (r = 0.89).He thinks that the necktie reduces blood flow to the brain,preventing the brain from receiving enough oxygen.Professor Johnston and his associates claim to have proven that wearing neckties causes strokes.What error has Professor Johnston made?
A)An r = 0.89 is not a very large r-value.
B)Professor Johnston is drawing a causal conclusion from correlational findings.
C)Not everyone who wears a necktie wears it very tight.
D)Professor Johnston should know that there are other ways for blood to reach the brain.

Question

Quizplus · Accepted Answer

Professor Johnston has made the error of drawing a causal conclusion from correlational findings. Correlation does not equal causation, so just because he found a strong positive correlation between wearing neckties and the frequency of strokes does not mean that wearing neckties causes strokes. There may be other factors at play that are causing both the wearing of neckties and the occurrence of strokes.

Professor Johnston Has Found a Strong Positive Correlation Between Wearing