BU385 Chapter 7: Chapter 7S- Learning Curves
Document Summary
Time required to perform task decreases with increasing repetitions learning curves/improvement curve show this. Degree of improvement and # of repetitions needed to realize the major portion of improvement is a function of the task being done. Short and routine = modest amount of improvement occurring first few repetitions. Complex and long = improvement occur over large number of repetitions. Learning curves have little relevance for planning or scheduling of routine short activities, but are relevant for complex long activities. Learning effect: time per unit decreases as # of units produced increases. Cra(cid:449)ford"s method: rate of decrease in unit time remains constant as # of units produced doubles. Wright"s method: i(cid:374)stead of ti(cid:373)e per u(cid:374)it, so(cid:373)e use a(cid:448)erage ti(cid:373)e (cid:894)up to a(cid:374)d i(cid:374)(cid:272)ludi(cid:374)g u(cid:374)it(cid:895) Experience curve: when unit cost is used instead of unit time. Major changes made once production is underway (product redesign, new equipment) can cause temporary increase in time per unit until workers adjust to change.
