| A company wants to assign 14 employees to 10 offices. Each employee has a preference for a certain office. | |||||||||||||||
| How should the company assign employees to the offices to maximize the preference of all employees? | |||||||||||||||
| Preferences (1=first, 10=last choice) | |||||||||||||||
| Office 1 |
Office 2 |
Office 3 |
Office 4 |
Office 5 |
Office 6 |
Office 7 |
Office 8 |
Office 9 |
Office 10 |
||||||
| Employee 1 | 3 | 2 | 1 | 4 | 6 | 5 | 8 | 9 | 10 | 7 | |||||
| Employee 2 | 5 | 3 | 2 | 6 | 1 | 7 | 9 | 8 | 4 | 10 | |||||
| Employee 3 | 10 | 8 | 1 | 9 | 7 | 4 | 3 | 6 | 2 | 5 | |||||
| Employee 4 | 7 | 3 | 2 | 9 | 5 | 4 | 8 | 6 | 1 | 10 | |||||
| Employee 5 | 1 | 3 | 6 | 8 | 5 | 2 | 9 | 10 | 7 | 4 | |||||
| Employee 6 | 4 | 9 | 1 | 5 | 6 | 8 | 2 | 7 | 10 | 3 | |||||
| Employee 7 | 2 | 1 | 10 | 9 | 5 | 3 | 6 | 8 | 4 | 7 | |||||
| Employee 8 | 6 | 5 | 1 | 3 | 2 | 4 | 7 | 8 | 9 | 10 | |||||
| Employee 9 | 8 | 9 | 10 | 5 | 4 | 3 | 2 | 1 | 6 | 7 | |||||
| Employee 10 | 9 | 10 | 3 | 2 | 5 | 4 | 1 | 7 | 8 | 6 | |||||
| Employee 11 | 7 | 3 | 5 | 2 | 9 | 8 | 1 | 10 | 4 | 6 | |||||
| Employee 12 | 6 | 5 | 1 | 9 | 10 | 2 | 3 | 4 | 7 | 8 | |||||
| Employee 13 | 6 | 8 | 10 | 9 | 1 | 2 | 3 | 4 | 5 | 7 | |||||
| Employee 14 | 6 | 3 | 5 | 9 | 1 | 2 | 10 | 4 | 8 | 7 | |||||
| Assignments | Office 1 |
Office 2 |
Office 3 |
Office 4 |
Office 5 |
Office 6 |
Office 7 |
Office 8 |
Office 9 |
Office 10 |
Total | Preference | |||
| Employee 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | |||
| Employee 2 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | |||
| Employee 3 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | |||
| Employee 4 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | |||
| Employee 5 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | |||
| Employee 6 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | |||
| Employee 7 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | |||
| Employee 8 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | |||
| Employee 9 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | |||
| Employee 10 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | |||
| Employee 11 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | |||
| Employee 12 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | |||
| Employee 13 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | |||
| Employee 14 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | |||
| Total | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | ||||
| Required | 1 | 1 | 1 | 1 | 2 | 1 | 2 | 2 | 2 | 1 | |||||
| Problem | |||||||||||||||
| A company wants to assign 14 employees to 10 offices. There are four offices that require 2 people. Each | |||||||||||||||
| employee has given their preference. A 1 means first choice, 2 means second choice, etc. How should the | |||||||||||||||
| company assign the people to the offices to optimize the preferences of the employees? | |||||||||||||||
| Solution | |||||||||||||||
| 1) The variables are the assignments of the people to different offices. On worksheet Offices these are | |||||||||||||||
| given the name Assignments. | |||||||||||||||
| 2) There are the following logical constraints | |||||||||||||||
| Assignments = binary | |||||||||||||||
| and the other constraints | |||||||||||||||
| Assignments_per_employee = 1 | |||||||||||||||
| Total_employees = Required_employees | |||||||||||||||
| 3) The objective is to optimize the preference of the employees. That means we have to minimize the sum | |||||||||||||||
| of the total preferences given to the assigned offices, defined on the worksheet as Total_preference. | |||||||||||||||
| Remarks | |||||||||||||||
| When everybody wants a different office, there will be no problems. If all employees prefer the same | |||||||||||||||
| office (more likely!), the problem gets more difficult and it might be necessary to give an employee 7th or | |||||||||||||||
| 8th choice. It might be wise, in that case, to add a constraint to say that no assignment worse than 5th | |||||||||||||||
| choice is given, for instance. This may cause the problem to be infeasible, i.e., there is no possible | |||||||||||||||
| solution. If this happens, you will have to relax the constraint on the assignments, e.g. no worse than 6th | |||||||||||||||
| or even 7th choice. | |||||||||||||||
