MD254: e-Service Operations Management

1. MD254: e-Service Operations Management Managing Waiting Lines in Traditional Services and e-Services

3. Background

4. Background Waiting lines are a part of any service Physical services have physical waiting lines Call centers have queues of phone calls e-Services have waiting times between when you click a URL in your browser and when the e-Service returns a web page During that time period, you are waiting in a virtual waiting line of peoples’ requests

5. Background Competitive importance of fast – or at least, reasonable – delivery speed Physical service People can see the waiting line, and this affects their behavior and perceptions Call center service operations People end up “on hold,” which can affect their behavior and perceptions e-Service 8-second rule of thumb for delivering web pages has gotten steadily faster over time

6. Queues and Queueing Systems

7. Queues and Queueing Systems Queue A line of waiting customers who require service from a service system made up of one or more servers

8. Queues and Queueing Systems Location of Queues Relative to Customer Customer goes to Server Retailing – queue builds up in front of cash register Restaurants – queue builds up at front door; customer’s food order queues in kitchen Server goes to Customer Plumber – queue is on a list of destinations to visit

9. Queues and Queueing Systems Networks of Queues Queueing Systems are often made up of networks of waiting lines Disney World longer queues are partitioned into subqueues different entertainment provided during each subqueue Telecommunications Services Phone calls travel across a queueing network of phone system devices e-Service Web servers, application servers, database servers, and so on, make up a network of queues that manage and process a waiting line of customers

10. Psychology of Waiting

11. Psychology of Waiting Physical Services People dislike empty time, so it is often good to fill up such time in useful ways Service related diversions (i.e., filling out forms) can be accomplished during waiting, to shorten the eventual service time, and make better use of service provider times (e.g., doctors) Customers worry about their place in line, and whether they’ve been forgotten, so it is often good to remind them you have not forgotten Customers have certain expectations about how a waiting line will be run, and when this expectation is violated (e.g., a later arrival being served first), they may get mad Experiences during waiting times are also part of the service experience, leading to good or bad word of mouth, and retaining or losing the customer

12. Psychology of Waiting e-Services Customers cannot usually see the queue of customers in front of their service request – they can only sit there and hope that the next web page comes up Difficult to see why service may be slow Often difficult to find non-electronic service personnel, to assist one with the e-service Offline activities (services delivered to home, delivery of products purchased online) provide major portions of perceived service queues Often good to keep customer informed about these

13. Queues in a Traditional Service

14. Queues in a Traditional Service Single Queue, Single Server Single Queue, Multiple Server Multiple Queue, Multiple Server Job Shop Multiple queue, Multiple server Jobs can flow from any server to any other server Batch Flow Jobs flow from server to server in groups Discrete Flow (Assembly) Line Each job individually visits a number of servers in a specific order

15. Queues in a Traditional ServiceAn Emergency Room

16. Queues in an e-Service

17. Queues in an e-ServiceCommon e-Service Processes

18. Queues in an e-Service

19. Queues in an e-ServiceA Network of Queues

20. Features of Queueing Systems

21. Features of Queueing Systems Calling population Arrival process Queue configuration Queue discipline Service process

22. Features of Queueing Systems Calling population Composition Homogeneous customers Heterogeneous customers (multiple classes of customers) How many groups? Characteristics of groups? Size Finite – how many? Infinite

23. Features of Queueing Systems Arrival process The demand for a service has temporal and spatial components that determine how demand arrives at the service system Nature Discrete/Fixed Scheduled Stochastic/Random Inter-arrival times (period between arrivals) are commonly assumed to be distributed exponentially Customer Behaviors Balking – seeing length of waiting line, and leaving before entering line Reneging – leaving the waiting line after being in it for a while

24. Features of Queueing Systems Queue configuration The number of queues, their locations, their spatial requirements, and their effects on customer behavior Single queue vs. multiple queues Queue traffic controller? (bouncer, lady in bank at lunchtime yelling out which line is empty) Jockeying behavior – customers leave one line for another shorter one

25. Features of Queueing Systems Queue discipline A policy established by management to select the next customer from the queue for service First-Come, First-Served (FCFS) Person who arrived first goes next Shortest Processing Time Job that will take the shortest time to process goes next Priority Based Queueing Disciplines Bouncer at bar lets in the “beautiful people” first – rest of us have to wait (or tip heavily to get past bouncer) until space is available late at night Emergency room helps people with really bad injuries first Many, many, many potential policies have been developed for different systems

26. Features of Queueing Systems Service process The tasks that must be accomplished to complete the process The number of servers The location of servers where the tasks are completed The length of time for completing each task

27. Summary

28. Summary All production systems have waiting lines – even the ones that are scheduled to try to eliminate waiting Queueing systems are important in all services – traditional and e-service Managers must understand how to model the traditional and e-services Several important features of queueing systems define how queues function