Quételet’s error
An introduction to Quételet's error, the fallacy of treating the average man as a norm or ideal, which can lead to flawed reasoning in statistics and everyday decision-making.
THE IDEA
Not worth a pastis—Quételet’s error—The average man is a monster—Let’s deify it—Yes or no—Not so literary an experiment
Forget everything you heard in college statistics or probability theory. If you never took such a class, even better. Let us start from the very beginning.
When to use it
Designing products for the 'average user' without considering who is excluded.
Using average grades to compare schools without accounting for distribution.
Relying on average life expectancy to plan retirement ignoring health variability.
FROM THEORY TO EVERYDAY LIFE
In practice
The average driver
Traffic planners design roads based on the average driving behavior, but this ignores the wide variation in driver skills and reactions, leading to unsafe conditions for both above and below average drivers.
A MOMENT TO REFLECT
Put it to work.
How can relying on averages obscure important differences within a population?
Why is it problematic to use the 'average person' as a standard for policy making?
In what ways might the fallacy of the average lead to unjust outcomes in hiring or education?
CONTINUE THE CONVERSATION
Source texts
- The Black Swan The Impact of the Highly Improbable With a new section On Robustness and Fragility (Nassim Nicholas Taleb)