Optimizing Call Center Staffing using Simulation and Analytic Center Cutting Plane Methods

Júlíus Atlason, Marina A. Epelman og Shane G. Henderson

We consider the problem of minimizing staffing costs in an inbound call center, while maintaining an acceptable level of service in multiple time periods. The problem is complicated by the fact that staffing level in one time period can affect the service levels in subsequent periods. Moreover, staff schedules typically take the form of shifts covering several periods. Interactions between sta±ng levels in different time periods, as well as the impact of shift requirements on the staffing levels and cost should be considered in the planning. Traditional sta±ng methods based on stationary queueing formulas do not take this into account. We present a simulation-based analytic center cutting plane method to solve a sample average approximation of the problem. We establish convergence of the method when the service level functions are discrete pseudocon-cave. An extensive numerical study of a moderately large call center shows that the method is robust and, in most of the test cases, outperforms traditional sta±ng heuristics that are based on analytical queueing methods.

Corporate Governance, Executive Compensation and Securities Litigation

Eric L. Talley og Guðrún Johnsen

It is generally accepted that good corporate governance, executive compensation and the threat of litigation are all important mechanisms for incentivizing managers of public corporations. While there are significant and robust literatures analyzing each of these policy instruments in isolation, their mutual relationship and interaction has received somewhat less attention. Such neglect is mildly surprising in light of a strong intuition that the three devices are structurally related to one another (either as complements or substitutes). In this paper, we construct an agency cost model of the firm in which corporate governance protections, executive compensation levels, and litigation incentives are all endogenously determined. We then test the predictions of the model using a firm-level data set including governance, executive compensation, and securities litigation variables. Consistent with our predictions, we find governance and compensation to be structural substitutes with one another, so that more protective governance structures tend to coincide with lower-powered incentives in executive contracts. Also consistent with our predictions, we find executive compensation and shareholder litigation appear to be structural complements to one another, so that higher powered incentives tend to catalyze more frequent litigation. In fact, we estimate that each 1% increase in the incentive component of a CEO's contract predicts 0.3% increase in the likelihood of a securities class action and a $3.4 million dollar increase in expected settlement costs. In addition, the complementarity of executive compensation and litigation allows us to formulate new ways to test for the effects of legal reform, such as the Private Securities Litigation Reform Act of 1995. The results of our preliminary tests appear inconsistent with the claims of the statute's proponents that the PSLRA systematically discouraged non-meritorious litigation without burdening meritorious claims, particularly for firms with relatively low volatility.