Transcript Learning Curve Analysis

Learning Curve Analysis
Learning Objective
After this class the students should be
able to:
Calculate the hours required to
produce determinate product taking
account the learning curve.
Time management
 The expected time to deliver this module is 50 minutes.
30 minutes are reserved for team practices and
exercises and 20 minutes for lecture.
Learning Curve
Past experience indicates that
individuals learn by experience
(i.e., get better and better at the
job by carrying out the tasks
more and more).
Warm-up – 30 minutes
 The student teams receive a bag containing
pieces and are asked to assembly a same set
for several times.
 One team’s member is invited to chronometer
the time that your team spend to assembly
the set.
 After the end, each team plots the results in a
software (excel) and try to fit an exponential
curve.
Learning curve
This phenomenon was first
reported by T. P. Wright in 1936.
But, the learning curve theory is
based on assumptions such as
those listed next Chase, R B.,
1981
Learning curve assumptions
 The time required to complete a specified
task or unit of a product or item will be less
each time the task is performed;
 The unit time will reduce at a decreasing rate;
 The decrease in time will follow a certain
pattern, such as negative exponential
distribution shape.
Learning Curve assumptions
 The learning curve may vary one product to
another and from one organization to another.
The rate of learning depends on factors such
as the quality of management and the
potential of the process and products
 Moreover, it may be said that any
change in personnel, process, or
product disrupts the learning curve.
Consequently, there is a need for the
utmost care in assuming that a learning
curve is continual and permanent.
Learning Curve Effects
Some Information on Learning Curve Effects in U.S. Industrial Sector
Number
Item/Area
Description
Time Period
Cumulative Learning Curve Slop
Parameter Percentage
1
Steel making
1920 1955
Units
Produced
(UP)
Production Worker
labor-hour per unit
produced
79
2
Handheld
calculators
1975 1978
UP
Average factory
selling price
74
3
Assembly of
aircrafts
1925 1957
UP
Direct labor
hours per unit
80
4
Ford Motor
Company
Model T
production
1910 1926
UP
Price
86
 The Table presents data on learning curve effects in the U.S. industrial
sector . An 80% learning rate is descriptive of certain operations in such
areas as ship construction, electronic data processing equipment,
automatic machine production, and aircraft instruments and frame
assemblies.
 The learning curves are found to be quite useful in a variety of
applications, including strategic evaluation of company and industry
performance, internal labor forecasting, establishing costs and budgets,
production planning, external purchasing, and subcontracting of items
 The learning curve theory is based on a doubling of productivity. More
specifically, when output or production doubles, the reduction in time
per unit affects the learning curve rate. For example, an 80% learning
rate means the second unit takes 80% of the time of the first unit, the
fourth unit takes 80% of the second unit, the eighth unit takes 80% of
the fourth unit, and so on.
Result
 We may write
LHm = LH1m C
Where:
LHm is the labor hours required to produce unit
LH1 is the labor hours to produce unit one or the
first unit.
C is the learning curve slope and is expressed by
log of the learning rate/(log2)
Discussion
 Each team has to present an analyze of its
results based on the theory presented in
class
Exercise
Assume that the learning rate for a
certain operation is 75% and it took
90 hours to produce the first unit.
Calculate the hours required to
produce the fifth unit.
Solution
By substituting the given data value into C equation, we
get
 C = log 0.75/log 2 = 0.4150
 Using the above value and the specified data in LHm =
LH1m C yields
 LH5 = 90(5)-0.4150
 = 46.15 hours
 It will take 46.15 hours to produce the fifth unit.
Reference
 “Engineering and Technology management
tools and applications” – Dhillon, B. S. Artec
House, Inc 2002.
 Operation Analysis Using Excel – Weida,
2000, Duxbury.