CALL CENTERS (CENTRES) - Faculty of Industrial Engineering and ...

isfaction. The contact-center “performance” may be restricted to a traditional productivity
measure such as the number of calls answered per hour or it may include a broader measure
of the quality of service, e.g., revenue earned per hour or the number of problems successfully
resolved per hour. The analysis is based on an idealized model of a contact center, in which the
number of employed agents is constant over time, assuming that a new agent is immediately hired
to replace each departing agent. The agent employment periods are assumed to be independent
and identically distributed random variables with a general agent-retention probability distribution,
which depends upon management policy and actions. The steady-state staff-experience
distribution is obtained from the agent-retention distribution by applying renewal theory. An
increasing real-valued function specifies the average performance as a function of agent experience.
Convenient closed-form expressions for the overall performance as a function of model
elements are derived when either the agent-retention distribution or the performance function
has exponential structure. Management actions may cause the agent-retention distribution to
change. The model describes the consequences of such changes upon the long-run average staff
experience and the long-run average performance.
Keywords: Contact centers, Call centers, Retention, Employee turnover, Churn, Agent job satisfaction,
Compensation, Autonomy, Stress, Stochastic models, Renewal theory, Stochastic comparisons
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