statistics · cause
Ecological fallacy
A pattern in the average can be false for each person.
A pattern that is true for groups is not necessarily true for the individuals inside those groups. Group averages can mislead about people.
Regions with higher average income also have higher average recycling. Does a person with higher income recycle more?
Across regions, places with higher average income also have higher average recycling rates.
Inside any single region, the people with higher income recycle less.
Drawing a conclusion about people from data that only describe groups is the mistake.
The group-level correlation can be produced by other regional factors and need not exist at the individual level.