The Wickelgren Power Law and the Ebbinghaus Savings Function

Wayne Wickelgren, who died on November 2, 2005, after a longbattle with Lou Gehrig’s disease, studied the time course offorgetting more assiduously and more effectively than anyonesince Hermann Ebbinghaus. In a classic article, Wickelgren(1974) derived an equation that is remarkable in several re-spects, including in its ability to characterize the famous Eb-binghaus (1885/1913) savings function. Under typical conditions,Wickelgren’s power law reduces tom ¼ lð1 þbtÞ