Hick's law

Terms from Artificial Intelligence: humans at the heart of algorithms

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Hick's Law is one of the few results in cognitve psychology with a precise formulation, namely that the time taken to mae a choice increases with the logarithmof the number of choices. That is, if someone has to make a choice between N alternatves, the reaction time T is given by:
      T   ∝   log( N )

In fact, the original experiments that gave to this were based on highly structured inputs that enabled 'binarychop' style decison strategies. Given a long list of randomly sorted alternatives there is at least a linear time to read the list. However, whether the exact time is logarithmic or linear, the qulaitiave result still holds: the more alterbatuves the longer ot takes a person to kae the decsions.

This isimportant when designing intelligent human-in-the-loop systems, as it is sensible to present muliple alternatives to the human, but not too many.

Used on Chap. 19: page 481