The City of Toronto Long Term Care Homes & Services (LTCH&S) division is one of the largest providers of long-term care in the Canadian province of Ontario, providing care to 2,640 residents at 10 homes across Toronto. Our collaboration with LTCH&S was initiated to facilitate the increasingly challenging task of scheduling nursing staff and reduce high absenteeism rate observed among the part-time nurses. We developed a spreadsheet-based scheduling tool to automate the generation of schedules and incorporate nurses' preferences for different shifts into the schedules. At the core of the scheduling tool is a hierarchical optimization model that generates a feasible schedule with the highest total preference score while satisfying the maximum possible demand. Feasible schedules had to abide by a set of complex seniority requirements which prioritized more senior nurses when allocating the available shifts. Our scheduling tool was implemented in a 391-bed home in Toronto. The tool allowed nursing managers to generate feasible schedules within a fraction of an hour, in contrast to the status-quo manual approach which could took up to tens of hours. In addition, the schedules successfully accounted for preferences with on average above 94% of the allocated shifts ranked as most preferred.

翻译：多伦多市长期护理所和服务部是加拿大安大略省提供长期护理的最大部门之一,为全多伦多10个家庭2 640名居民提供护理。我们与多伦多中心合作,协助安排护理人员和减少非全时护士中高缺勤率这一日益艰巨的任务。我们开发了一个基于电子表格的时间安排工具,将时间安排的生成自动化,并将护士对不同轮班的偏好纳入其中。在时间安排工具的核心是一种等级优化模式,它产生可行的时间表,总优惠得分最高,同时满足最大需求。可行的时间表必须遵守一套复杂的年资要求,在分配现有轮班时优先安排更多的高级护士。我们的时间安排工具在多伦多391张床位的家中实施。该工具允许护理管理人员在不到一小时的时间内制定可行的时间表,而采用按情况说明的手册方法可以长达数十小时。此外,时间表成功地记录了平均超过所分配的94%的更优先的轮班次。