research-article

Does the Erlang C model fit in real call centers?

Authors:

Thomas R. Robbins,

D. J. Medeiros,

Terry P. HarrisonAuthors Info & Claims

WSC '10: Proceedings of the Winter Simulation Conference

Pages 2853 - 2864

Published: 05 December 2010 Publication History

Abstract

We consider the Erlang C model, a queuing model commonly used to analyze call center performance. Erlang C is a simple model that ignores caller abandonment and is the model most commonly used by practitioners and researchers. We compare the theoretical performance predictions of the Erlang C model to a call center simulation model where many of the Erlang C assumptions are relaxed. Our findings indicate that the Erlang C model is subject to significant error in predicting system performance, but that these errors are heavily biased and most likely to be pessimistic, i.e. the system tends to perform better than predicted. It may be the case that the model's tendency to provide pessimistic (i.e. conservative) estimates helps explain its continued popularity. Prediction error is strongly correlated with the abandonment rate so the model works best in call centers with large numbers of agents and relatively low utilization rates.

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Cited By

Mathijsen BJanssen ALeeuwaarden JZwart B(2018)Robust heavy-traffic approximations for service systems facing overdispersed demandQueueing Systems: Theory and Applications10.5555/3288543.328856590:3-4(257-289)Online publication date: 1-Dec-2018
https://dl.acm.org/doi/10.5555/3288543.3288565
Liston PByrne JKeogh OByrne P(2017)Beyond callsProceedings of the 2017 Winter Simulation Conference10.5555/3242181.3242513(1-12)Online publication date: 3-Dec-2017
https://dl.acm.org/doi/10.5555/3242181.3242513
Robbins THuschka TChick S(2016)Evaluating the fit of the Erlang A model in high traffic call centersProceedings of the 2016 Winter Simulation Conference10.5555/3042094.3042320(1790-1801)Online publication date: 11-Dec-2016
https://dl.acm.org/doi/10.5555/3042094.3042320
Show More Cited By

Index Terms

Does the Erlang C model fit in real call centers?
1. Computing methodologies
  1. Modeling and simulation
    1. Model development and analysis
      1. Model verification and validation
2. Software and its engineering
  1. Software notations and tools
    1. General programming languages
      1. Language types

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Information & Contributors

Information

Published In

cover image ACM Conferences

WSC '10: Proceedings of the Winter Simulation Conference

December 2010

3519 pages

ISBN:9781424498642

Sponsors

IIE: Institute of Industrial Engineers
INFORMS-SIM: Institute for Operations Research and the Management Sciences: Simulation Society
SCS: Shanghai Computer Society
SIGSIM: ACM Special Interest Group on Simulation and Modeling

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Winter Simulation Conference

Publication History

Published: 05 December 2010

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WSC10

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IIE
INFORMS-SIM
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WSC10: Winter Simulation Conference

December 5 - 8, 2010

Maryland, Baltimore

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WSC '10 Paper Acceptance Rate 184 of 281 submissions, 65%;

Overall Acceptance Rate 3,413 of 5,075 submissions, 67%

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Cited By

Mathijsen BJanssen ALeeuwaarden JZwart B(2018)Robust heavy-traffic approximations for service systems facing overdispersed demandQueueing Systems: Theory and Applications10.5555/3288543.328856590:3-4(257-289)Online publication date: 1-Dec-2018
https://dl.acm.org/doi/10.5555/3288543.3288565
Liston PByrne JKeogh OByrne P(2017)Beyond callsProceedings of the 2017 Winter Simulation Conference10.5555/3242181.3242513(1-12)Online publication date: 3-Dec-2017
https://dl.acm.org/doi/10.5555/3242181.3242513
Robbins THuschka TChick S(2016)Evaluating the fit of the Erlang A model in high traffic call centersProceedings of the 2016 Winter Simulation Conference10.5555/3042094.3042320(1790-1801)Online publication date: 11-Dec-2016
https://dl.acm.org/doi/10.5555/3042094.3042320
Alves MMatias Rde Freitas Filho PBuckley SMiller J(2014)Modeling and simulation applied to capacity planning of voice gatewaysProceedings of the 2014 Winter Simulation Conference10.5555/2693848.2694243(3143-3154)Online publication date: 7-Dec-2014
https://dl.acm.org/doi/10.5555/2693848.2694243

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