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Glossary » power law of practice

power law of practice

an expression of time to perform a task based on practice trials, saying that people improve in speed at a decaying exponential rate.

Tn = T1 n-a, a ~ 0.4

Tn = the time to perform a task after n trials.
T1 = the time to perform a task in the first trial.
n = the number of trials.

Cognitive modeling approaches such as GOMS apply this to making predictions of human performance.