Estimate

you’ll see them for 2.5 seconds. how many?

flash-count a dot cloud, then see how far people typically undercount

A glance isn't enough time to count a scattered group, only to guess, and most guesses land under the true number. The comparison spread shown afterward is a modeled curve built around that tendency, not real answers from other people.

Concepts: probability, perception.

An interactive you play with one thumb, on Wundr.