Hick–Hyman Law, explained.
The Hick–Hyman law, often called Hick's Law, relates choice response time to the uncertainty among possible responses under specified conditions.
Why it happens
When several outcomes can require different actions, the user must determine which response applies. Equally likely alternatives carry more uncertainty as their number grows. A familiar organization can also reduce search and interpretation demands, which are not captured by counting choices alone.
The Hick–Hyman law relates choice response time to uncertainty about the required response under particular experimental conditions.
Read the result
Start a search and select the named item. Try multiple rounds before comparing menu sizes. The displayed bits describe theoretical uncertainty; your time includes reading and visual search, so this is not a fitted laboratory response-time curve.
A worked example
Finding an action in a menu
A screen offers twelve unfamiliar actions with similar labels.
Grouping related actions and improving their names may help a user identify the relevant one without simply deleting choices.
Evaluate the actual task: fewer visible choices may shift effort into hidden menus rather than eliminate it.
OPTIONAL DEEPER DETAILGo deeper: inside the model
Inside this model
Each round selects one equally likely item from a shuffled menu. The theoretical uncertainty is log2(number of choices) bits. The recorded browser time also includes visual search; no universal timing coefficient is assumed.
Where this idea is useful
A practical use
Clear grouping and familiar labels can make a menu easier to navigate. Merely hiding options can also make important actions harder to find.
A common misconception
“Every menu should contain as few items as possible.”
Reducing visible items can add navigation or obscure needed features. Organization, familiarity and the task affect the result.
What this explanation leaves out
- This task is an illustration, not a replication of laboratory choice-reaction experiments. Visual search, reading, familiarity and accessibility tools affect the measured time.
Do all choices have the same uncertainty?
No. The experiment uses equal selection probabilities. When some responses are much more likely, their probability distribution changes the relevant uncertainty.
Does the user face too many possibilities, unclear labels, or unnecessary search?
Associated thinkers
Further reading
Explore the original research or the teaching reference behind this experiment.