Availability Heuristic

In a study, participants listen to either:

A list of 19 famous women and 20 less famous men

A list of 20 famous men and 19 less famous woman

Afterwards, some were asked to recall the names they could remember, and then if the list they had heard contained more men or women.

Unsurprisingly, the famous names were more readily recalled; but, interestingly, the vast majority of participants then incorrectly assumed that the gender of the more famous people were the majority gender in the list they heard.

Read more: Attest – Official Publication

Denominator Neglect

Picture two urns stood on a table in front of you.

You’re given the opportunity to pick a marble from one of them, and drawing a red marble wins a prize.

The first urn has 10 marbles in it, 1 of which is red.

The second urn has 100 marbles in it, 8 of which are red.

Which urn would you choose? It doesn’t seem a tricky decision: your chances of drawing a red marble out of the first urn are greater (10%) than your chances of drawing a red marble out of the second urn (8%).

And yet, as Daniel Kahneman describes in Thinking, Fast and Slow:

‘About 30-40% of students (the survey participants) choose the urn with the larger number of winning marbles, rather than the urn that provides a better chance of winning.’

… Read more: Attest – Official Publication

The Jones Effect

‘The outside influences are always pouring in upon us, and we are always obeying their orders and accepting their verdicts. The Smiths like the new play; the Joneses go to see it, and they copy the Smith verdict’ – Mark Twain, Corn Pone Opinions

Although not the originator of the phrase ‘The Jones Effect’, Mark Twain has a point: people follow people – they follow their habits, likes, dislikes, and opinions.

(…) Read more: Attest – Official Publication