Answer to Question 1
Answer: A confounding variable is an outside variable related to the primary variables in a correlations study. It can cause problems by making it appear that the two primary variables are related when in fact they are not and the effect is being caused by the confounding variable.
Answer to Question 2
Answer: Correlation studies cannot prove causation. For example, most people who live in apartments have cats. But it is that they are actually cat people who prefer cats? Or do they own cats because dogs are not allowed or because they don't have a yard?
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