OM5 Chapter 14: Operations Scheduling and Sequencing
Discussion Questions
1. Discuss how you decide to schedule your school assignments. Do your informal scheduling
rules correspond to any of those in this chapter?
Many students will probably recognize that they use a shortest processing time
2. Explain why appointments are necessary for many professional services. (Hint: How do
services differ from goods as described in Chapter 1?) List and explain some key issues and
decisions that must be addressed in designing appointment systems.
Seven differences between goods and services are described in Chapter 1. You might begin
Several of these differences provide the foundation to answer this question. In fact, one can
argue they are even more pronounced for PSO than RSOs (routine service organizations).
For example, services cannot be stored as physical inventory. Service capacity is the
Finally, service capacity in a PSO is perishable. That is, once a doctor or lawyer does not use
an hour of his or her billable idle time, it cannot be stored for later sale—the revenue
3. Scheduling and sequencing are typically viewed from a technical perspective; that is, they are
focused on minimizing quantitative measures such as lateness or cost. However, schedules
also have intangible effects on customers, employees, and the perception of service quality.
Discuss what some of these intangible effects might be and how managers should consider
them when constructing schedules.
Some not so tangible effects include: customer inconvenience (not really the right time);
imbalances in work load and schedules can cause discontent among employees as one sees
the other as getting favorable treatment; wage price differential for odd shift schedules not
4. Why is staff scheduling in a service environment a difficult task? What can managers do to
ensure that staff schedules are effective and efficient?
This question differs from #2 in that it includes both RSOs and PSOs. Although similar
reasons cited in the answer to #2 help address this question, other issues include the use of
multiple shifts, part-time employees, and varying demand. For example, call centers
5. Explain the advantages and disadvantages of SPT and EDD sequencing rules. Under what
circumstances might you prefer one over the other?
The SPT sequencing rule maximizes workstation utilization and minimizes average job flow
time and work-in-process inventory. This is a very powerful sequencing rule. One
Problems and Activities
Note: an asterisk denotes problems for which an Excel spreadsheet template on the CourseMate
Web site may be used.
1. Write a short one-page paper listing the advantages and disadvantages of using part-time
employees to help meet demand.
The main advantage of part-time employees is to help minimize cost. Other advantages
The main disadvantage of part-time employees is do they have adequate production or
service management skills compared to full-time employees. If interacting with the
customer, the service-providing organization carries the risk of more service upsets and
2. Research a desktop or Web-based scheduling software system and write a short one-page
paper describing its features and capabilities, and any benefits from real world organizations
that adopted the software.
The expected answer to this question should be similar to the box in the chapter titled
“Software to Schedule Anywhere.” Their Web site claims their software helps reduce
3. Research and write a short paper (two pages maximum) on how efficient vehicle scheduling
and routing are accomplished. If possible, provide some examples of commercial software
that are used for vehicle scheduling and routing and their capabilities.
A Google search reveals about 900,000 hits for “vehicle routing software” so your students
StreetSyncTM Desktop is an affordable and easy-to-use route scheduling software package
ArcLogisticsTM is a complete solution for complex routing and scheduling problems.
4. Interview an operations manager at a nearby manufacturing or service company to find out
about scheduling problems the company faces and how they are addressed.
This question can help make the text material relevant and also demonstrate to the student the
complexity of real scheduling issues. One point to make in class is that if a company cannot
5. A hospital emergency room needs the following numbers of nurses.
Day M T W T F S S
Min. number 4 3 2 4 7 8 5
Notice this is a difficult target-staffing pattern ranging from a minimum of 4 to 8 nurses. There
Step M T W T F S S
14324785
6. A supermarket has the following minimum personnel requirements during the week. Each employee
is required to have two consecutive days off. How many regular employees are required and what is
a good schedule?
Day Mon Tue Wed Thur Fri Sat Sun
Minimum Personnel 3 4 5 3 5 6 5
Step M T W T F S S
7. These six jobs are to be scheduled on a single machine:
Job 1 2 3 4 5 6
a. Suppose the jobs are processed in numerical order. Compute the average flowtime
after each job is completed.
b. In what order would the jobs be processed using the SPT rule? Compute the average
flowtime after each job is completed. Compare this answer with your answer to part
a.
Of course, the longest processing time job waits until the end to be work on and in this
8.* An insurance claims work area has five claims waiting for processing as follows.
Job Processing Time Due Date (Di)
Compute the average flowtime, tardiness, and lateness for the following sequences:
SPT sequence: 4-5-2-3-1
Earliest due date sequence: 4-5-3-1-2
Sequence 2-1-5-3-4
SPT is recommended. It minimizes average flow time and number of jobs in system.