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st101/Week 2/12 Correlation vs Causation Discussion Forums Resources

st101/Week 2/12 Correlation vs Causation Discussion Forums Resources This is example taken from internet: For example, suppose the fall term of classes ends in December. The manager of a toystore in the local mall hires one new worker. This worker is a college student named Stacy. She wants to do some work before spring term classes start. After Stacy is hired, the store's sales shoot up by 300%. "Wow!" the manager says to herself, "That Stacy is a fantastic sales worker! I haven't hired anyone else but Stacy. Still, since we hired her, our sales have tripled! I'd better give her a raise!" Is the manager's conclusion logical? Is it true that Stacy must be fantastic at her job? Odds are, nine out of ten readers at this point are nodding, thinking to themselves, "Yeah, it makes sense to me. You hire a new girl, and the sales go up. No other girls were hired. It must be the new girl's work." On the other hand, the tenth reader stopped and thought, "Wait a minute.... Didn't you say Stacy was hired in December? That's right around Christmas time. Maybe the reason the sales went up wasn't because of Stacy, but because of the time of year." The manager's conclusion now vanishes in a puff of logic.