Peoples level of happiness usually returns to a baseline even after rare live events.

Availability Heuristic


The availability heuristic refers to our tendency to give more weight to information that readily comes to mind. This means that people often overestimate the probability of rare events, such as being eaten by a shark, murdered by a serial killer or die in a tsunami because they get a lot of publicity in the media when they occur.

Image of National Lottery homepage for availability bias
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Lottery and casino companies benefit from availability bias by regularly making announcements about jackpot winners and how it has changed their lives. Of course we hardly ever hear anything about the many millions of people who don’t win money on the lottery or at the casino. As a result people think they are much more likely to win the lottery or slots jackpot than is really the case.

The UK’s Brexit vote may also have been influenced by availability bias. Over the years many misleading and false stories have been published in the British media about the EU. In one case the Telegraph and the Express vastly over estimated the number of long-term EU migrants coming into the country by including the number of short-term migrants (less than 1 year) over 5 consecutive years.

In another instance the media claimed the EU was to end the UK’s control over asylum seekers coming in the country.  Given the frequency of such stories in the media it is likely that many people will have over-estimated how many were in fact true.    Together with confirmation bias this may have had a significant impact on how people chose to vote in the EU referendum.


Conversion marketing – Glossary of Conversion Marketing.

Cognitive biases – Why do people prefer gut instinct to research?

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