3. • Suppose there are 5 machines and 5 jobs to be
performed.
• 1 machine can do only 1 job at a time.
• How the machines should be assigned to the
jobs?
• Given – the cost of performing a job on a
machine.
• An Assignment Problem (AP) is always square.
• The assignment is done on a one-to-one
matching basis.
4. • Only one allocation is possible in a given row or
column.
• The AP is inherently degenerate, as the
assignment is done on a one-to-one matching
basis. (In the above 5 machine 5 job problem,
there would be 25 cells, but allocation can be
made only in 5 cells, whereas 9 cells should be
allocated.)
• Total number of assignments possible = n!
6. Hungarian Method
Machine
X Y Z
Job
A 25 31 35
B 15 20 24
C 22 19 17
• Machine opportunity and job opportunity cost to
be determined.
• The minimum element of a particular row or
column to be subtracted from all elements of that
row or column.
12. Machine
X Y Z
Job
A 0 4 10
B 0 3 9
C 5 0 0
Machine Opportunity Cost
2nd
Reduced Cost (Total Opportunity Cost) Matrix
13. 0 4 10
0 3 9
5 0 0
• Optimal assignment is that
assignment where total
opportunity cost is zero.
• We draw horizontal and
vertical lines so as to cross
all the zero elements using
the minimum number of
lines.
14. 0 4 10
0 3 9
5 0 0
• Optimal assignment is that
assignment where total
opportunity cost is zero.
• We draw horizontal and
vertical lines so as to cross
all the zero elements using
the minimum number of
lines.
• If the minimum number of lines required to do
so is equal to the number of rows or columns,
then optimum allocation is possible.
15. 0 4 10
0 3 9
5 0 0
• Optimal assignment is that
assignment where total
opportunity cost is zero.
• We draw horizontal and
vertical lines so as to cross
all the zero elements using
the minimum number of
lines.
• If the minimum number of lines required to do
so is equal to the number of rows or columns,
then optimum allocation is possible.
• In this case it is not possible.
16. 0 4 10
0 3 9
5 0 0
• We identify the minimum
element not covered by
lines.
17. 0 4 10
0 3 9
5 0 0
• We identify the minimum
element not covered by
lines.
• In this case it is 3.
19. Assignment Model: Applications
• Assign salespeople to sales territories.
• Assign vehicles to routes.
• Assign accountants to client accounts.
• Assign contracts to bidders through
systematic evaluation of bids from competing
suppliers.
• Assign naval vessels to patrol sectors.
• Schedule teachers to classes.
20. Assignment Model: Applications
• Matching men to machines according to
pieces produced per hour by each individual
on each machine.
• Matching teams to projects by the expected
cost of each team to accomplish each project.