Sharks represent an example of a common fear that is wildly exaggerated. More people are killed by cows or horses each year than by sharks.  The availability bias is when we believe examples of things that come easily to mind are far more likely to occur than is actually the case. Media coverage on the Internet or TV makes a big difference. Even movies such as "Jaws" can change our perceptions. When rare events occur, they become very visible to us as they receive heavy coverage by the media. This means we are more likely to recall these events. If something is more easily recalled in memory, we may conclude that it will occur with a higher probability.  

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