Staffing a call center with uncertain non-stationary arrival rate and flexibility

We consider a multi-period staffing problem in a single-shift call center. The call center handles inbound calls, as well as some alternative back-office jobs. The call arrival process is assumed to follow a doubly non-stationary stochastic process with a random mean arrival rate. The inbound calls...

Full description

Saved in:
Bibliographic Details
Published in:OR Spectrum 2012-07, Vol.34 (3), p.691-721
Main Authors: Liao, Shuangqing, Koole, Ger, van Delft, Christian, Jouini, Oualid
Format: Article
Language:English
Subjects:
Arrivals
Business administration
Business and Management
Calculus of Variations and Optimal Control
Optimization
Call centers
Discretization
domain_shs.gestion.man-op
Flexibility
Humanities and Social Sciences
Mathematical models
Mathematical programming
Operating costs
Operations management
Operations research
Operations Research/Decision Theory
Optimization
Probability distribution
Programming
Regular Article
Stochastic models
Studies
Workforce planning
Workload
Workloads
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We consider a multi-period staffing problem in a single-shift call center. The call center handles inbound calls, as well as some alternative back-office jobs. The call arrival process is assumed to follow a doubly non-stationary stochastic process with a random mean arrival rate. The inbound calls have to be handled as quickly as possible, while the back-office jobs, such as answering emails, may be delayed to some extent. The staffing problem is modeled as a generalized newsboy-type model under an expected cost criterion. Two different solution approaches are considered. First, by discretization of the underlying probability distribution, we explicitly formulate the expected cost newsboy-type formulation as a stochastic program. Second, we develop a robust programming formulation. The characteristics of the two methods and the associated optimal solutions are illustrated through a numerical study based on real-life data. In particular we focus on the numerical tractability of each formulation. We also show that the alternative workload of back-office jobs offers an interesting flexibility allowing to decrease the total operating cost of the call center.
ISSN:0171-6468
1436-6304
DOI:10.1007/s00291-011-0257-0