How to play
A lamp lights up: tap it as fast as you can. First one lamp, then two, four and eight. Wait for the light.
Tap the lamp · Or keys 1 to 8
Free in your browser, with ten levels that get harder. No account; your best scores stay on your device.
What the study found
With up to ten lamps and a key for each, the time to respond rose by roughly the same amount every time the number of equally likely choices doubled. It became known as Hick's law. Tapping a screen adds travel time that his keys did not have.
William Hick · Quarterly Journal of Experimental Psychology, 1952
Why it matters
Every extra option adds a little thinking time, for everyone, in a steady and predictable way. Behaviour at work follows patterns too. KOZMO asks how often specific things happen and turns the answers into evidence a team can understand and act on.
It is for fun: the game does not measure you.
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