Waiting Line Models and Service Improvement

1. Waiting Line Models and Service Improvement

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4. 4 Waiting Lines / Queues Waiting in lines does not add enjoyment Waiting in lines does not generate revenue There are costs in providing waiting space Lines can result in loss of business(customers leave, refusing to wait) Loss of goodwill Overall reduction in customer satisfaction Congestion may disrupt other business operations

5. What can help reduce waiting times?

6. 6 Approaches that help… Reduce perceived waiting time Magazines in waiting rooms Radio/television In-flight movies Filling out forms mirrors When all else fails, derive benefits from waiting Place impulse buy items near checkout (“endcaps”) Advertise other goods/services

7. 7 What’s important to the Customer? Length of the line when I arrive How long I have to wait

8. 8 What’s important to the Service Provider? How many people I have to hire to service customers (clerks, cashiers, baggers, etc.) (Hopefully) the level of service provided

9. 9 Waiting Lines You have just been hired as the new assistant manager of a new Costco store. You are in charge of customer service. You determine that: 60 shoppers arrive per hour on average You can process 50 shoppers per hour on average with the number of cashiers Will your service be any good? Will your customers be satisfied?

10. 10 Waiting Lines 60 shoppers arrive per hour on average You can process 60 shoppers per hour on average Will your service be any good? Will your customers be satisfied?

11. 11 Waiting Lines 60 shoppers arrive per hour on average You can process 70 shoppers per hour on average Will your service be any good? Will your customers be satisfied?

12. 12 Waiting Lines: United States What’s an acceptable time to wait in line at:

13. 13 Waiting Lines What is a “reasonable” waiting time? Is your willingness to wait dependent upon the type of establishment? Are there cultural differences? Can we establish a model of wait time to reduce average wait time?

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16. 16 Waiting in line to get add slips signed in HTM302

17. 17 Elements of Waiting Line Analysis

18. 18 Components of Queuing System

19. 19 Elements of a Waiting Line

20. 20 Elements of a Waiting Line

21. 21 Elements of a Waiting Line

22. 22 Basic Waiting Line Structures

23. 23 Single-Channel Structures

24. 24 Multi-Channel Structures

25. 25 Predicting Waiting Times Later we’ll show how you can mathematically predict the performance of a waiting line, in terms of: Number of people waiting in line Expected waiting time But first, let’s look first at some model results to get an intuitive feel as to what happens.

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29. 29 Multi-Channel Structures

30. 30 Which is better?

31. 31 Which is better?

32. 32 Two servers, four possibilities; which is best?

33. 33 Multi-Channel Structures(that the book doesn’t deal with…)

34. 34 Multi-Channel Structures(that the book doesn’t deal with…)

35. 35 Multi-Channel Structures

36. 36 Operating Characteristics

37. 37 Cost Relationship in Waiting Line Analysis

38. 38 Cost Relationship in Waiting Line Analysis

39. 39 Cost Relationship in Waiting Line Analysis

40. 40 Waiting Line Costs and Quality Service

41. 41 Cost Relationship in Waiting Line Analysis

42. 42 Cost Relationship in Waiting Line Analysis

43. 43 Basic Single-Server Model

44. 44 Formulas for Single-Server Model

45. 45 Formulas for Single-Server Model

46. 46 An example You manage a small grocery store, with one checker for scanning, collecting payment, and bagging groceries. The arrival rate is 24/hr, service rate 30/hr, so average waiting time is 8 minutes. You want to improve checkout time, so you are considering adding: A second employee to bag groceries OR A second checker Which is better?

47. 47 An example

48. 48 Waiting Line Cost Results

49. Simulation Model

50. 50 Informal feedback Write a “2 minute” journal to be handed in immediately The journal should briefly summarize: Major points learned Areas not understood or requiring clarification