What's the best example of "correlation does not imply causation"?

1. My stat professor’s favorite was the correlation between ice cream sales and crime rate in Detroit, as there was a pretty strong positive correlation between the two.
   — mistyskye14


2. Data from about 20 years ago showed higher wages for teachers correlated with lower average SAT scores.
   — DemonDuJour


3. The decline of pirates and rise in global warming.
   — couch120






4. The spurious correlations generator at tylervigen.com/discover is always fun. It uses real data to align datasets that have no connection to eachother. Did you know that the divorce rate in Maine is closely correlated to the per capita consumption of margarine? Or, that the number of motorcycle riders killed in collisions with animals is correlated to eBay's total merchandise volume? Or that deaths from falling off a train is correlated to online retailers' revenue on Thanksgiving? (99% confidence value in all cases) If you're willing to go for less than 99% you can get *really* crazy. The deaths due to cancer on Thursdays correlates with the number of lawyers in Tennessee at about 97%.
   — anschauung


5. 75% of murderers ate some form of potato in the week before they killed someone.
   — Gwafa_Hazid


6. In college they used to use "ice cream sales and boating accidents", since both see an uptick in the summer months.
   — Tom_Navy






7. This one: https://xkcd.com/552/
   — sew_butthurt


8. [Global temperature and number of pirates](https://sparrowism.soc.srcf.net/home/graph.png)
   — BanMeBabyOneMoreTime


9. 100% of people who have ever drank water have died. 100% of the people today who have had water are going to die. The secret for eternal life must be to stop drinking water.
   — Rust_Dawg






10. 100% of people who take vaccines die.
    — SlothReactionTime