© 2007 Pearson Education Learning Curve Analysis Supplement G

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© 2007 Pearson Education

Learning CurveAnalysis

Supplement GSupplement G

© 2007 Pearson Education

Learning Curves

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Learning curveLearning curve

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© 2007 Pearson Education

Learning Curves

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Learning curveLearning curve

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Learning period

Showing the learning period

© 2007 Pearson Education

Learning Curves

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Learning curveLearning curve

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Learning Learning periodperiod

Standard time

Showing the learning period and the time when standards are calculated

© 2007 Pearson Education

Developing Learning Curves

In developing learning curves we make the following assumptions:

The direct labor required to produce the n + 1st unit will always be less than the direct time of labor required for the nth unit.

Direct labor requirements will decrease at a declining rate as cumulative production increases.

The reduction in time will follow an exponential curve.

kn = k1nb

where k1 = direct labor hours for the 1st unit

n = cumulative number of units produced b = log r / log 2

r = learning rate

© 2007 Pearson Education

80% Conversion Factors for the Cumulative Average Number of

Direct Labor Hours per Unit

© 2007 Pearson Education

90% Conversion Factors for the Cumulative Average Number of

Direct Labor Hours per Unit

© 2007 Pearson Education

Example G.1 Developing the 80% Learning Curve

Manufacturer of diesel locomotives:

Labor hours required for first unit = 50,000

Learning rate = 80%

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© 2007 Pearson Education

Example G.1 Estimating Direct Labor Requirements

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Labor hours required for first unit = 50,000

Learning rate = 80%

© 2007 Pearson Education

Example G.1 using the formula

Labor hours required for 40th unit

k40 = 50,000(40)(log 0.8)/(log 2)

Labor hours required for first unit = 50,000

Learning rate = 80%

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© 2007 Pearson Education

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k40 = 50,000(40)-0.322

Labor hours required for first unit = 50,000

Learning rate = 80%

Example G.1 using the formula

© 2007 Pearson Education

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4040 8080 120120 160160 200200 240240 280280Cumulative units producedCumulative units produced

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k40 = 50,000(0.30488)

Labor hours required for first unit = 50,000

Learning rate = 80%

Example G.1 using the formula

© 2007 Pearson Education

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4040 8080 120120 160160 200200 240240 280280Cumulative units producedCumulative units produced

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k40 = 15,244 hours

Labor hours required for first unit = 50,000

Learning rate = 80%

Example G.1 using the formula

© 2007 Pearson Education

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4040 8080 120120 160160 200200 240240 280280Cumulative units producedCumulative units produced

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k40 = 15,244 hours

Labor hours required for first unit = 50,000

Learning rate = 80%

Example G.1 using the formula

© 2007 Pearson Education

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4040 8080 120120 160160 200200 240240 280280Cumulative units producedCumulative units produced

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k40 = 15,244 hours

Labor hours required for first unit = 50,000

Learning rate = 80%

Example G.1 using the formula

© 2007 Pearson Education

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4040 8080 120120 160160 200200 240240 280280Cumulative units producedCumulative units produced

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Cumulative average labor hours =

Labor hours required for first unit = 50,000

Learning rate = 80%n

1 1.000002 0.900003 0.83403. .. .. .

38 0.4363439 0.4330440 0.4298464 0.37382

128 0.30269

80% Learning Rate(n = cumulative production)

Example G.1 using Conversion Factors

© 2007 Pearson Education

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Labor hours required for first unit = 50,000

Learning rate = 80%

Cumulative average labor hours = 50,000(0.42984)

n

1 1.000002 0.900003 0.83403. .. .. .

38 0.4363439 0.4330440 0.4298464 0.37382

128 0.30269

80% Learning Rate(n = cumulative production)

Example G.1 using Conversion Factors

© 2007 Pearson Education

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Labor hours required for first unit = 50,000

Learning rate = 80%

Cumulative average labor hours = 21,492 hours

n

1 1.000002 0.900003 0.83403. .. .. .

38 0.4363439 0.4330440 0.4298464 0.37382

128 0.30269

80% Learning Rate(n = cumulative production)

Example G.1 using Conversion Factors

© 2007 Pearson Education

Labor hours required for first unit = 50,000

Learning rate = 80%

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4040 8080 120120 160160 200200 240240 280280Cumulative units producedCumulative units produced

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Example G.1 using Unit-doublings

© 2007 Pearson Education

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4040 8080 120120 160160 200200 240240 280280Cumulative units producedCumulative units produced

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Labor hours required for first unit = 50,000

Learning rate = 80%

Example G.1 using Unit-doublings

© 2007 Pearson Education

50 50 –

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4040 8080 120120 160160 200200 240240 280280Cumulative units producedCumulative units produced

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Labor hours required for first unit = 50,000

Learning rate = 80%

Second unit = 50,000(80%)

Example G.1 using Unit-doublings

© 2007 Pearson Education

50 50 –

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4040 8080 120120 160160 200200 240240 280280Cumulative units producedCumulative units produced

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Labor hours required for first unit = 50,000

Learning rate = 80%

Second unit = 40,000 hours

Example G.1 using Unit-doublings

© 2007 Pearson Education

50 50 –

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4040 8080 120120 160160 200200 240240 280280Cumulative units producedCumulative units produced

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Labor hours required for first unit = 50,000

Learning rate = 80%

Fourth unit = 40,000(80%)

Example G.1 using Unit-doublings

© 2007 Pearson Education

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Labor hours required for first unit = 50,000

Learning rate = 80%

Fourth unit = 32,000 hours

Example G.1 using Unit-doublings

© 2007 Pearson Education

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The 80% Learning Curve forExample G.1

© 2007 Pearson Education

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4040 8080 120120 160160 200200 240240 280280Cumulative units producedCumulative units produced

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The 80% Learning Curve forExample G.1

© 2007 Pearson Education

Application G.1 Estimating Direct Labor Requirements

The 1st unit of a new product is expected to take 1,000 hours. The learning rate is 80%, how much time should the 50th unit take?

© 2007 Pearson Education

Units perUnits per CumulativeCumulativeMonthMonth MonthMonth UnitsUnits

11 22 2222 33 5533 55 101044 88 181855 1212 3030

Example G.2Estimating Labor Requirements

© 2007 Pearson Education

Example G.2Estimating Labor Requirements

Units perUnits per CumulativeCumulativeMonthMonth MonthMonth UnitsUnits

11 22 2222 33 5533 55 101044 88 181855 1212 3030

Cumulative CumulativeAverage Time Total Hours

Month per Unit for All Units

n

1 1.000002 0.950003 0.915404 0.889055 0.86784. .. .. .

30 0.6909064 0.62043

128 0.56069

90% Learning Rate(n = cumulative production)

© 2007 Pearson Education

Units perUnits per CumulativeCumulativeMonthMonth MonthMonth UnitsUnits

11 22 2222 33 5533 55 101044 88 181855 1212 3030

Cumulative CumulativeAverage Time Total Hours

Month per Unit for All Units

1 30,000(0.95000) = 28,500

n

1 1.000002 0.950003 0.915404 0.889055 0.86784. .. .. .

30 0.6909064 0.62043

128 0.56069

90% Learning Rate(n = cumulative production)

Example G.2Estimating Labor Requirements

© 2007 Pearson Education

Units perUnits per CumulativeCumulativeMonthMonth MonthMonth UnitsUnits

11 22 2222 33 5533 55 101044 88 181855 1212 3030

Cumulative CumulativeAverage Time Total Hours

Month per Unit for All Units

1 30,000(0.95000) = 28,500 28,500(2) = 57,0002 30,000(0.86784) = 26,035

n

1 1.000002 0.950003 0.915404 0.889055 0.86784. .. .. .

30 0.6909064 0.62043

128 0.56069

90% Learning Rate(n = cumulative production)

Example G.2Estimating Labor Requirements

© 2007 Pearson Education

Units perUnits per CumulativeCumulativeMonthMonth MonthMonth UnitsUnits

11 22 2222 33 5533 55 101044 88 181855 1212 3030

Cumulative CumulativeAverage Time Total Hours

Month per Unit for All Units

1 30,000(0.95000) = 28,500 28,500(2) = 57,0002 30,000(0.86784) = 26,035 26,035(5) = 130,1753 30,000(0.79945) = 23,983 23,983(10) = 239,8304 30,000(0.74080) = 22,224 22,224(18) = 400,0325 30,000(0.69090) = 20,727 20,727(30) = 621,810

n

1 1.000002 0.950003 0.915404 0.889055 0.86784. .. .. .

30 0.6909064 0.62043

128 0.56069

90% Learning Rate(n = cumulative production)

Example G.2Estimating Labor Requirements

© 2007 Pearson Education

Units perUnits per CumulativeCumulativeMonthMonth MonthMonth UnitsUnits

11 22 2222 33 5533 55 101044 88 181855 1212 3030

Cumulative CumulativeAverage Time Total Hours

Month per Unit for All Units

1 30,000(0.95000) = 28,5002 30,000(0.86784) = 26,0353 30,000(0.79945) = 23,9834 30,000(0.74080) = 22,2245 30,000(0.69090) = 20,727

Example G.2Estimating Labor Requirements

© 2007 Pearson Education

Units perUnits per CumulativeCumulativeMonthMonth MonthMonth UnitsUnits

11 22 2222 33 5533 55 101044 88 181855 1212 3030

Cumulative CumulativeAverage Time Total Hours

Month per Unit for All Units

1 30,000(0.95000) = 28,500 28,500(2) = 57,0002 30,000(0.86784) = 26,0353 30,000(0.79945) = 23,9834 30,000(0.74080) = 22,2245 30,000(0.69090) = 20,727

Example G.2Estimating Labor Requirements

© 2007 Pearson Education

Units perUnits per CumulativeCumulativeMonthMonth MonthMonth UnitsUnits

11 22 2222 33 5533 55 101044 88 181855 1212 3030

Cumulative CumulativeAverage Time Total Hours

Month per Unit for All Units

1 30,000(0.95000) = 28,500 28,500(2) = 57,0002 30,000(0.86784) = 26,035 26,035(5) = 130,1753 30,000(0.79945) = 23,9834 30,000(0.74080) = 22,2245 30,000(0.69090) = 20,727

Example G.2Estimating Labor Requirements

© 2007 Pearson Education

Units perUnits per CumulativeCumulativeMonthMonth MonthMonth UnitsUnits

11 22 2222 33 5533 55 101044 88 181855 1212 3030

Cumulative CumulativeAverage Time Total Hours

Month per Unit for All Units

1 30,000(0.95000) = 28,500 28,500(2) = 57,0002 30,000(0.86784) = 26,035 26,035(5) = 130,1753 30,000(0.79945) = 23,983 23,983(10) = 239,8304 30,000(0.74080) = 22,224 22,224(18) = 400,0325 30,000(0.69090) = 20,727 20,727(30) = 621,810

Example G.2Estimating Labor Requirements

© 2007 Pearson Education

Units perUnits per CumulativeCumulativeMonthMonth MonthMonth UnitsUnits

1 2 22 3 53 5 104 8 185 12 30

Cumulative CumulativeAverage Time Total Hours

Month per Unit for All Units

1 30,000(0.95000) = 28,500 28,500(2) = 57,0002 30,000(0.86784) = 26,035 26,035(5) = 130,1753 30,000(0.79945) = 23,983 23,983(10) = 239,8304 30,000(0.74080) = 22,224 22,224(18) = 400,0325 30,000(0.69090) = 20,727 20,727(30) = 621,810

Month 1:

Example G.2Estimating Labor Requirements

© 2007 Pearson Education

Units perUnits per CumulativeCumulativeMonthMonth MonthMonth UnitsUnits

1 2 22 3 53 5 104 8 185 12 30

Cumulative CumulativeAverage Time Total Hours

Month per Unit for All Units

1 30,000(0.95000) = 28,500 28,500(2) = 57,0002 30,000(0.86784) = 26,035 26,035(5) = 130,1753 30,000(0.79945) = 23,983 23,983(10) = 239,8304 30,000(0.74080) = 22,224 22,224(18) = 400,0325 30,000(0.69090) = 20,727 20,727(30) = 621,810

Month 1: 57,000 – 0 = 57,000 hours

Example G.2Estimating Labor Requirements

© 2007 Pearson Education

Units perUnits per CumulativeCumulativeMonthMonth MonthMonth UnitsUnits

1 2 22 3 53 5 104 8 185 12 30

Cumulative CumulativeAverage Time Total Hours

Month per Unit for All Units

1 30,000(0.95000) = 28,500 28,500(2) = 57,0002 30,000(0.86784) = 26,035 26,035(5) = 130,1753 30,000(0.79945) = 23,983 23,983(10) = 239,8304 30,000(0.74080) = 22,224 22,224(18) = 400,0325 30,000(0.69090) = 20,727 20,727(30) = 621,810

Month 1: 57,000 – 0 = 57,000 hoursMonth 2: 130,175 – 57,000 = 73,175 hours

Example G.2Estimating Labor Requirements

© 2007 Pearson Education

Units perUnits per CumulativeCumulativeMonthMonth MonthMonth UnitsUnits

1 2 22 3 53 5 104 8 185 12 30

Cumulative CumulativeAverage Time Total Hours

Month per Unit for All Units

1 30,000(0.95000) = 28,500 28,500(2) = 57,0002 30,000(0.86784) = 26,035 26,035(5) = 130,1753 30,000(0.79945) = 23,983 23,983(10) = 239,8304 30,000(0.74080) = 22,224 22,224(18) = 400,0325 30,000(0.69090) = 20,727 20,727(30) = 621,810

Month 1: 57,000 – 0 = 57,000 hoursMonth 2: 130,175 – 57,000 = 73,175 hoursMonth 3: 239,830 – 130,175 = 109,655 hoursMonth 4: 400,032 – 239,830 = 160,202 hoursMonth 5: 621,810 – 400,032 = 221,778 hours

Example G.2Estimating Labor Requirements

© 2007 Pearson Education

Units perUnits per CumulativeCumulativeMonthMonth MonthMonth UnitsUnits

1 2 22 3 53 5 104 8 185 12 30

Cumulative CumulativeAverage Time Total Hours

Month per Unit for All Units

1 30,000(0.95000) = 28,500 28,500(2) = 57,0002 30,000(0.86784) = 26,035 26,035(5) = 130,1753 30,000(0.79945) = 23,983 23,983(10) = 239,8304 30,000(0.74080) = 22,224 22,224(18) = 400,0325 30,000(0.69090) = 20,727 20,727(30) = 621,810

Month 1: 57,000 – 0 = 57,000 /150 = 380 employeesMonth 2: 130,175 – 57,000 = 73,175 /150 = 488 employeesMonth 3: 239,830 – 130,175 = 109,655 /150 = 731 employeesMonth 4: 400,032 – 239,830 = 160,202 /150 = 1068 employeesMonth 5: 621,810 – 400,032 = 221,778 /150 = 1479 employees

Example G.2Estimating Labor Requirements

© 2007 Pearson Education

Application G.2 Estimating Cumulative Labor Hours

An example of using the learning model to test budget constraints:

A company has a contract to make a product for the

first time. The total budget for the 38-unit job is 15,000

hours. The first unit took 1000 hours, and the rate of

learning is expected to be 80 percent.

Do you think the 38-unit job can be completed within

the 15,000-hour budget?

How many additional hours would you need for a

second job of an 26 additional units?

© 2007 Pearson Education

Application G.2First 38-unit Job

© 2007 Pearson Education

Application G.2Second additional 26-unit Job

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