Chapter 5 Designing Services 5-1 Lecture Outline Service Economy Characteristics of Services Service Design Process Tools for Service Design Waiting Line Analysis for Service Improvement
Copyright 2011 John Wiley & Sons, Inc. 5-2 Service Economy Copyright 2011 John Wiley & Sons, Inc. 5-3 U.S. Economy Copyright 2011 John Wiley & Sons, Inc. 5-4 Characteristics of Services Services
acts, deeds, or performances Goods tangible objects Facilitating services accompany almost all purchases of goods Facilitating goods accompany almost all service purchases Copyright 2011 John Wiley & Sons, Inc. 5-5 Continuum From Goods to Services Source: Adapted from Earl W. Sasser, R.P. Olsen, and D. Daryl Wyckoff, Management of
Service Operations (Boston: Allyn Bacon, 1978), p.11. Copyright 2011 John Wiley & Sons, Inc. 5-6 Characteristics of Services Service are inseparable from delivery Services tend to be decentralized and dispersed Services are consumed more often than products Services can be easily emulated Services are intangible Service output is variable Services have higher customer contact Services are perishable Copyright 2011 John Wiley & Sons, Inc.
5-7 Service Design Process Copyright 2011 John Wiley & Sons, Inc. 5-8 Service Design Process Service concept purpose of a service; it defines target market and customer experience Service package
mixture of physical items, sensual benefits, and psychological benefits Service specifications performance specifications design specifications delivery specifications Copyright 2011 John Wiley & Sons, Inc. 5-9 Service Process Matrix Copyright 2011 John Wiley & Sons, Inc.
5-10 High vs. Low Contact Services Design Decision High-Contact Service Low-Contact Service Facility Convenient to location customer Facility layout Near labor or transportation source Must look presentable, Designed for
accommodate efficiency customer needs, and facilitate interaction with customer Copyright 2011 John Wiley & Sons, Inc. 5-11 High vs. Low Contact Services Design Decision High-Contact Service Quality control
More variable since Measured against customer is involved in established process; customer standards; testing expectations and and rework possible perceptions of quality may differ; customer to correct defects present when defects occur Capacity Excess capacity
required to handle peaks in demand Copyright 2011 John Wiley & Sons, Inc. Low-Contact Service Planned for average demand 5-12 High vs. Low Contact Services Design Decision High-Contact Service
Worker skills Must be able to interact well with customers and use judgment in decision making Technical skills Scheduling Must accommodate customer schedule Customer concerned only
with completion date Copyright 2011 John Wiley & Sons, Inc. Low-Contact Service 5-13 High vs. Low Contact Services Design Decision High-Contact Service Service process
Mostly front-room Mostly backactivities; service may room activities; change during delivery planned and in response to executed with customer minimal interference Service package Varies with customer; includes environment as well as actual
service Copyright 2011 John Wiley & Sons, Inc. Low-Contact Service Fixed, less extensive 5-14 Tools for Service Design Service blueprinting
line of influence line of interaction line of visibility line of support Front-office/Backoffice activities Copyright 2011 John Wiley & Sons, Inc. Servicescapes space and function ambient conditions signs, symbols, and artifacts Quantitative techniques
5-15 Service Blueprinting Copyright 2011 John Wiley & Sons, Inc. 5-16 Service Blueprinting Copyright 2011 John Wiley & Sons, Inc. 5-17 Elements of Waiting Line Analysis Operating characteristics
average values for characteristics that describe performance of waiting line system Queue a single waiting line Waiting line system consists of arrivals, servers, and waiting line structure Calling population source of customers; infinite or finite Copyright 2011 John Wiley & Sons, Inc. 5-18
Copyright 2011 John Wiley & Sons, Inc. 5-19 Elements of Waiting Line Analysis Arrival rate ()) frequency at which customers arrive at a waiting line according to a probability distribution, usually Poisson Service rate ()) time required to serve a customer, usually described by negative exponential distribution Service rate must be higher than arrival rate () < )) Queue discipline order in which customers are served
Infinite queue can be of any length; length of a finite queue is limited Copyright 2011 John Wiley & Sons, Inc. 5-20 Elements of Waiting Line Analysis Channels number of parallel servers for servicing customers Phases
number of servers in sequence a customer must go through Copyright 2011 John Wiley & Sons, Inc. 5-21 Operating Characteristics Operating characteristics are assumed to approach a steady state Copyright 2011 John Wiley & Sons, Inc. 5-22
Traditional Cost Relationships As service improves, cost increases Copyright 2011 John Wiley & Sons, Inc. 5-23 Psychology of Waiting Waiting rooms magazines and newspapers televisions Bank of America mirrors Supermarkets
magazines impulse purchases Copyright 2011 John Wiley & Sons, Inc. 5-24 Psychology of Waiting Preferential treatment Grocery stores: express lanes for customers with few purchases Airlines/Car rental agencies: special cards available to frequent-users or for an additional fee Phone retailers: route calls to more or less experienced salespeople based on customers sales history
Critical service providers services of police department, fire department, etc. waiting is unacceptable; cost is not important Copyright 2011 John Wiley & Sons, Inc. 5-25 Waiting Line Models Single-server model simplest, most basic waiting line structure Frequent variations (all with Poisson arrival rate)
exponential service times general (unknown) distribution of service times constant service times exponential service times with finite queue exponential service times with finite calling population Copyright 2011 John Wiley & Sons, Inc. 5-26 Basic Single-Server Model Assumptions Poisson arrival rate exponential service times first-come, first-served
queue discipline infinite queue length infinite calling population Copyright 2011 John Wiley & Sons, Inc. Computations ) = mean arrival rate ) = mean service rate n = number of customers in line 5-27 Basic Single-Server Model
P0 = probability that no customers are in queuing system ( ) 1 ) L= )
probability of n customers in queuing system Pn = ( ) ( )( ) ) ) n P0 = ) )
Copyright 2011 John Wiley & Sons, Inc. average number of customers in queuing system n 1 ) ) ) ) ) average number of customers
in waiting line Lq = )2 ) () )) 5-28 Basic Single-Server Model average time customer spends in queuing system W=
1 = ) ) probability that server is busy and a customer has to wait (utilization factor) L ) average time customer spends waiting in line Wq =
) ) () )) Copyright 2011 John Wiley & Sons, Inc. = ) ) probability that server is idle and customer can be served I=1 =1
) ) = P0 5-29 Basic Single-Server Model Example l = 24 m = 30 Copyright 2011 John Wiley & Sons, Inc. 5-30 Basic Single-Server Model Example Copyright 2011 John Wiley & Sons, Inc.
5-31 Service Improvement Analysis Waiting time (8 min.) is too long hire assistant for cashier? increased service rate hire another cashier? reduced arrival rate Is improved service worth the cost? Copyright 2011 John Wiley & Sons, Inc. 5-32 Excel Single-Server Solution
D4/(D5-D4) (1/(D5-D4))*60 (D4/D5)*(D5-D4)*60 Copyright 2011 John Wiley & Sons, Inc. 5-33 Advanced Single-Server Models Constant service times occur most often when automated equipment or machinery performs service Finite queue lengths occur when there is a physical limitation to length of waiting line
Finite calling population number of customers that can arrive is limited Copyright 2011 John Wiley & Sons, Inc. 5-34 Advanced Single-Server Models Copyright 2011 John Wiley & Sons, Inc. 5-35 Advanced Single-Server Model Probability of zero customers
Copyright 2011 John Wiley & Sons, Inc. 5-36 Basic Multiple-Server Model Single waiting line and service facility with several independent servers in parallel Same assumptions as single-server model s) > ) s = number of servers servers must be able to serve customers faster than they arrive Copyright 2011 John Wiley & Sons, Inc. 5-37 Basic Multiple-Server Model
probability that there are no customers in system 1 P0 = n = s 1 1 ) n 1 ) s s) n=0 n! ( ) + ( )( ) ) s!
) s) - ) probability of n customers in system 1 ) n P0, for n > s ns s!s ) Pn = 1 ) n P0, for n s n! ) {
Copyright 2011 John Wiley & Sons, Inc. () () 5-38 Basic Multiple-Server Model probability that customer must wait 1 Pw = L= s! ()
) ) s) s s) ) )) ()/))s (s 1)! (s) )) W= 2 L
) Copyright 2011 John Wiley & Sons, Inc. P0 P0 + Lq = L ) ) Wq = W ) )
1 ) = Lq ) ) = s) 5-39 Basic Multiple-Server Model Example Three-server system Copyright 2011 John Wiley & Sons, Inc.
5-40 Basic Multiple-Server Model Example Copyright 2011 John Wiley & Sons, Inc. 5-41 Basic Multiple-Server Model Example Copyright 2011 John Wiley & Sons, Inc. 5-42 Basic Multiple-Server Model Example To cut waiting time, add another service rep Four-server System
Copyright 2011 John Wiley & Sons, Inc. 5-43 Multiple-Server Waiting Line in Excel Copyright 2011 John Wiley & Sons, Inc. 5-44 Multiple-Server Waiting Line in Excel Copyright 2011 John Wiley & Sons, Inc. 5-45