【正文】 94 ? Empirical Findings ? Results ? SC = for reasonably large firm ? SC = for very large firms ? Interpretation ? Combining partial loads at an intermediate location lowers cost management difficulties with very large firms. Economies of Scope in the Trucking Industry Chapter 7 Slide 95 Dynamic Changes in CostsThe Learning Curve ? The learning curve measures the impact of worker’s experience on the costs of production. ? It describes the relationship between a firm’s cumulative output and amount of inputs needed to produce a unit of output. Chapter 7 Slide 96 The Learning Curve Cumulative number of machine lots produced Hours of labor per machine lot 10 20 30 40 50 0 2 4 6 8 10 Chapter 7 Slide 97 The Learning Curve Hours of labor per machine lot 10 20 30 40 50 0 2 4 6 8 10 ? The horizontal axis measures the cumulative number of hours of machine tools the firm has produced ? The vertical axis measures the number of hours of labor needed to produce each lot. Chapter 7 Slide 98 ? The learning curve in the figure is based on the relationship: ??? BNL1 a n d 0b e t w e e n is a n d p o s i t i v e a r e c o n s t a n t s a r e a n d o u t p u t ofu n i t p e r i n p u t l a b o r p r o d u c e do u t p u t of u n i t s c u m u l a t i v e??B amp。 ABA,LN??Dynamic Changes in CostsThe Learning Curve Chapter 7 Slide 99 ? ? L equals A + B and this measures labor input to produce the first unit of output ? ? Labor input remains constant as the cumulative level of output increases, so there is no learning :0??If:1?NIfDynamic Changes in CostsThe Learning Curve Chapter 7 Slide 100 ? ? L approaches A, and A represent minimum labor input/unit of output after all learning has taken place. ? ? The more important the learning effect. :in c re a s e s a n d 0 NIf ??:la rg e r T h e ?Dynamic Changes in CostsThe Learning Curve Chapter 7 Slide 101 The Learning Curve Cumulative number of machine lots produced Hours of labor per machine lot 10 20 30 40 50 0 2 4 6 8 10 ??The chart shows a sharp drop in lots to a cumulative amount of 20, then small savings at higher levels. Doubling cumulative output causes a 20% reduction in the difference between the input required and minimum attainable input requirement. Chapter 7 Slide 102 ? Observations 1) New firms may experience a learning curve, not economies of scale. 2) Older firms have relatively small gains from learning. Dynamic Changes in CostsThe Learning Curve Chapter 7 Slide 103 Economies of Scale Versus Learning Output Cost ($ per unit of output) AC1 B Economies of Scale A AC2 Learning C Predicting the Labor Requirements of Producing a Given Output 10 20 .80 ( + ) 30 .70 ( + ) 40 .64 ( + ) 50 .60 ( + ) 60 .56 ( + ) 70 .53 ( + ) 80 and over .51 ( + ) Cumulative Output PerUnit Labor Requirement Total Labor (N) for each 10 units of Output (L) Requirement Chapter 7 Slide 105 ? The learning curve implies: 1) The labor requirement falls per unit. 2) Costs will be high at first and then will fall with learning. 3) After 8 years the labor requirement will be and per unit cost will be half what it was in the first year of production. Dynamic Changes in CostsThe Learning Curve Chapter 7 Slide 106 ? Scenario ? A new firm enters the chemical processing industry. ? Do they: 1) Produce a low level of output and sell at a high price? 2) Produce a high level of output and sell at a low price? The Learning Curve in Practice Chapter 7 Slide 107 The Learning Curve in Practice ? How would the learning curve influence your decision? Chapter 7 Slide 108 ? The Empirical Findings ? Study of 37 chemical products ? Average cost fell % per year ? For each doubling of plant size, average production costs fall by 11% ? For each doubling of cumulative output, the average cost of production falls by 27% ? Which is more important, the economies of scale or learning effects? The Learning Curve in Practice Chapter 7 Slide 109 ? Other Empirical Findings ? In the semiconductor industry a study of seven generations of DRAM semiconductors from 19741992 found learning rates averaged 20%. ? In the aircraft industry the learning rates are as high as 40%. The Learning Curve in Practice Chapter 7 Slide 110 ? Applying Learning Curves 1) To determine if it is profitable to enter an industry. 2) To determine when profits will occur based on plant size and cumulative output. The Learning Curve in Practice Chapter 7 Slide 111 Estimating and Predicting Cost ? Estimates of future costs can be obtained from a cost function, which relates the cost of production to the level of output and other variables that the firm can control. ? Suppose we wanted to derive the total cost curve for automobile production. Chapter 7 Slide 112 Total Cost Curve for the Automobile Industry Quantity of Cars Variable cost General Motors Toyota Ford Chrysler Volvo Honda Nissan Chapter 7 Slide 113 ? A linear cost function (does not show the Ushaped characteristics) might be: ? The linear cost function is applicable only if marginal cost is constant. ? Marginal cost is represented by . Q?? VC?Estimating and Predicting Cost Chapter 7 Slide 114 ? If we wish to allow for a Ushaped average cost curve and a marginal cost that is not constant, we might use the quadratic cost function: 2 VC ?? ??Estimating and Predicting Cost Chapter 7 Slide 115 ? If the marginal cost curve is not linear, we might use a cubic cost function: 32 VC Q ??? ???Estimating and Predicting Cost Chapter 7 Slide 11