Operations management by stevenson 9th ch7s

7S Learning Curves McGraw-Hill/Irwin Copyright © 2007 by The McGraw-Hill Companies, Inc All Learning Objectives  Explain the concept of learning curves  Make time estimates based on learning curves  List and briefly describe some of the main applications of learning curves  Outline some of the cautions and criticisms of learning curves  Estimate learning rates from data on job times 7S-2 Learning Curves  Learning curves: the time required to perform a task decreases with increasing repetitions 7S-3 Learning Effect Time per repetition Figure 7S.1 Number of repetitions 7S-4 Learning with Improvements Time per unit Figure 7S.2 Average Improvements may create a scallop effect in the curve Time 7S-5 Applications of Learning Curves 1.Manpower planning and scheduling 2.Negotiated purchasing 3.Pricing new products 4.Budgeting, purchasing, and inventory planning 5.Capacity Planning 7S-6 Worker Learning Curves Time/cycles Figure 7S.4 A (underqualified) B (average) Standard time C (overqualified) One week Training time 7S-7 Cautions and Criticisms  Learning rates may differ from organization to organization  Projections based on learning curves should be viewed as approximations  Estimates based the first unit should be checked for valid times  At some point the curve might level off or even tip upward 7S-8 Cautions and Criticisms  Some improvements may be more apparent than real  For the most part, the concept does not apply to mass production  Learning curves sometimes fail to include carryover effects  Life cycles, flex manufacturing can affect application of learning curves 7S-9