Shift scheduling in call centers with multiple skill sets and transportation costs

Workforce plans in call centers, mostly working 24 hours a day and 7 days a week, have to satisfy both customer service levels and personnel constraints. Moreover, in large metropolitans such as Istanbul, call centers provide the transportation of the staff, so that shuttle costs constitute a major part of the total operational costs. We present a mathematical model which minimizes the transportation costs while satisfying service level and personnel constraints. We test our model with data from call centers.