Partial cross training in call centers with uncertain arrivals and global service level agreements

Inbound call center operations are challenging to manage; there is considerable uncertainty in estimates of arrival rates, and the operation is often subject to strict service level constraints. This paper is motivated by work with a provider of outsourced technical support services in which most projects (client specific support operations) include an inbound tier one help desk subject to a monthly service level agreement (SLA). Support services are highly specialized and a significant training investment is required, an investment that is not transferable to other projects. We investigate the option of cross training a subset of agents so that they may serve calls from two separate projects, a process we refer to as partial pooling. Our paper seeks to quantity the benefits of partial pooling and characterize the conditions under which pooling is most beneficial. We find that low levels of cross training yield significant benefit.

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