Hick's law

Hick-Hyman law, is a human-computer interaction model that describes the time it takes for a user to make a decision as a function of the possible choices he or she has. Given n equally probable choices, the average reaction time T required to choose among them is approximately

T = blog₂(n + 1)

where b is a constant that can be determined empirically by fitting a line to measured data.

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