Question

Please help. There is a strong positive linear correlation between the number of rainy days and the number of grapes produced on a grape plant. Does this mean that more rainy days cause the grape plants to produce more?

Answer 1

PLEASE, DO NOT go with the expert answer! That is sadly false.

The real answer is Option C: No. Any number of factors could also be affecting the number of grapes produced.

Explanation: Correlation Does NOT imply causation. In other words, a correlation between two quantities just means that they tend to change together. It can not prove that a change in one quantity causes a change in the other. No matter what your common sense tells you, or how strong the correlation is, in this case both linear and positive, you NEED more information to prove a cause-and-effect relationship. In this case, you don’t hav enough information to prove that more rainy days cause an increase in grape plant growth.

Hope this helps! Stay curious and safe, everyone! :D

Side Note: The phrase “Correlation is NOT the same as causation” can keep you safe from many misleading news stories and exaggerated advertising claims as well as answer this Algebra question. ;)