Hybrid flexibility strategy on personnel scheduling: Retail case study

This study evaluates the potential benefits of incorporating labor flexibility into personnel scheduling. The solution methodology develops, in an innovative way, a hybrid strategy of labor flexibility that combines the following two flexibility strategies: (i) flexible contracts, which allow to relax the duration of the shifts and the number of weekly hours employees must work; and (ii) multiskilled staff, employees trained to work on multiple task types. A mixed integer linear programming model is proposed to determine how many employees are required in each type of contract, and how many of them will be multiskilled employees and in which task types. Results using real data from a Chilean retail firm show the potential benefits of the proposed hybrid flexibility strategy in relation to experiments where flexibility is not considered (i.e., without flexible contracts and multiskilling), or even, when scenarios consider only one of the two flexibility strategies. The increases in the number of multiskilled employees are mainly produced by demand variability than by their respective size. Regarding the staff composition, empirical results show that on average the proportion of full-time employees with respect to part-time employees is approximately 1:3. It is also shown that the most attractive contracts are those that have short workdays.