decisions · paradox
Ellsberg paradox
A known risk feels safer than a risk with no stated odds.
One urn has a known mix. The other has an unknown mix. Which urn do you draw from?
You win if you draw a red ball. Which urn do you choose?
Most people choose the known urn both times.
That pair of choices cannot be explained by any fixed belief about the unknown urn.
The preference is for known probabilities over unknown ones.