# Testing for statistical valididty

"In Chile, where they typically dive alone, three of the six attacks since 1963 proved fatal," McCosker said. "Whereas, in California and Oregon, since 1950, only nine of 93 attacks were fatal."

The quote refers to white shark attacks on divers. The claim is that these attacks tend to be fatal more often when divers go out alone (typical of Chile) rather than with companions (typical of California and Oregon). Does this claim have statistical validity?

What statistical approach can I use to answer this question

• What comprises an "attack" instance? If a group of 10 divers go out and the group encounters a shark, is that one attack or is it ten? If that's the case, it's like saying Russian Roulette is safer when playing with friends, which is true but conveys the wrong impression. – AdamO Mar 16 '18 at 18:16

           Fatal      Non-fatal           Total