Alpha6: Complex Rostering Reduced to Six Steps


Defining the problem:

In many organisations business activity comes in ebb and flows based on demands from their customers. Whilst this can be forecast to some degree based on orders, shipments, contracts and seasons of the year etc, there is a high degree of complexity in ensuring sufficient staff are rostered to reflect the level of activity. This complexity arises from the working rules, policies and practices that limit staff assignments; Union Rules, Health and Safety Rules, EU working time rules, breaks between shifts, maximum shift lengths, holiday rules and internal policies all constrain the ability to map the right number of staff to achieve the right level of activity at the right time.

The result is that many organisations tend to roster to meet a constant somewhere between the ebb and flow of the activity levels (if indeed they have measured these). The problem is compounded as managers often do not consider absences (such as holiday entitlement) when they device the roster.

The consequence of these omissions is that often staff are over-rostered – e.g. present when there is little or no work to be done and absent (under-rostered) when there is a high demand of work. The result is that overtime and agency workers are deployed to meet the demand or else the organisation maybe damaged in terms of reputation, Service Level Agreement or in terms of financial penalties.

One way of avoiding the risk is to factor in the costs of overtime and agency work to avoid delays but this makes the organisation uncompetitive and risks losing customers or failing to acquire new business as a result.

Fool’s Gold:
in the past electronic solutions have been developed that attempt to map shifts and rosters to demand through complex algorithms and brute force mapping. The solutions have often been expensive, highly complicated with only IT personnel able to tweak rules and parameters and often long delays between each attempt to identify the correct pattern. The systems often return unworkable rosters that will not meet union rules and are based on a singular fallacy that there is such a thing as a perfect roster. An optimal roster can still be an unworkable one based on the internal preferences and policies of the organisation. These preferences often cannot be codified in a fully electronic system and the missing element is the human factor.

Alpha6 Methodology
Alpha6 is a methodology and process that has been developed and honed over 20 years to create optimal rosters that both meet the requirements of the business and the written and unwritten rules around staff working times. But most importantly it also includes the human factor in guiding the process from each step forward. Alpha6 done manually is not pain free; it requires training, skill and collaboration from other team members.

Alpha1: Demand to Requirements
The start of the process is to identify the demand levels and translate them into requirements. Demand are the activities that need to be completed over a week broken down by between 15 and 60-minute intervals. The activity could be building a widget or packing etc. The important element is when these activities need to start (e.g. when the shipment arrives) and be completed by.

From this Raw business level view of demand, you can with knowledge of the duration each activity takes, and quantity translate these into a requirements grid. Again, this is by 15 to 60-minute intervals over each day for a week. You know have a set of requirements of how many staff you need by each 15-60 segment of the day and week.

However, there is an immediate sense check to do on the requirements grid. Staff do not come into work for just 15 minutes so we need to look at how sensible the requirements and apply some annealing – softening of the requirements.

So, for example, your faithful transposing of demand into requirements (say by 15 minutes) may show as follows: 8:15 = 5, 8:30 = 1, 8:45 = 5 – you will not be sending 4 people home at 8:30 so amending the requirements to 8:15 = 4, 8:30 = 4, 8:45 = 4 will iron out the undoable without impacting significantly either on cost or productivity

Alpha2: Constraints
Understanding and documenting the constraints will save you huge amount of time.
These include the contracted hours of staff, their holiday entitlement, average time off work due to training or sickness, the minimum and maximum shift lengths that have been agreed internally, the number of shifts that can be worked in a row, the minimum and maximum off duty days that can be used.  There may also be rules around how many nights can be worked in a row that is different from how many earlies or days.

Alpha3: Shifts and Requirements
With both the requirements and constraints identified the next process is to select a number of shifts that fit within the constraints identified that can satisfy the requirements. Without an electronic system, you will need to narrow down these shifts before you attempt this stage. In general, the process of mapping shifts to requirements is a two-way process where adapting shift start/end times and durations becomes a learning process. At the end of the process you will have identified the number of shifts and the type of shifts that meet the requirements. By aligning the shift durations and quantity you will be able to calculate the number of staff required to full fill the requirements.

Alpha4: Planning for absence
Whilst Alpha3 provides the number staff to fulfil the requirements it does not consider staff holiday, absence and training. If you need 60 staff to fulfil the requirements, then you must also factor in their holidays and cover. If staff have 20 days holiday a year then that is 1200 days holiday which is an additional 5 staff required (because cover staff also get holiday). This cover needs to be spread over the period of a year and applied to any “tension” days or shifts (e.g. it may be that staff are more likely to take off Saturday and Sundays as holiday or night shifts). You may also factor in things like training or sickness. The main calculation here is how much to plan for versus how much to deal with through overtime. In some cases, your calculation might reveal you need 4.5 people for cover. In this scenario, it might be more cost effective to roster 4 more people and deal with .5 as overtime.

Alpha5: OFF DUTY
With your completed staffing level you now start with a pattern, one week (row) for each staff member. Thus, if you have a requirement for 67 staff the pattern will go for 67 weeks and there will be 67 lines in your pattern (with columns Mon to Sun). Obviously, staff do not work 7 days a week but given the requirements we know how many staff are needed on any given day and subtract that from the number of staff calculated. At the bottom of the pattern we know the total number of off duties for each day of the pattern. The process now is to plug in the required number of off-duties on each day for each row of the pattern. However, in general the 2 golden rules are that staff prefer weekends off and want a minimum of 2 off duties in a row. A roster that has off duty/on duty/off duty is likely to be rejected by staff.  The best approach is to start from Saturday/Sunday and work backwards/forwards ensuring that all off-duties are included. Be cognisant of the period between off duties and the rules about how many on duty shifts employees should work in a row. The key point here is that staff generally care more about when they are NOT working than when they are working. Getting this right is a critical stage.

Alpha6: ON DUTY
With the Off-duty roster completed the next step is to plug in the on-duty shifts. Based on the previous steps you will know how many of each shift need to be done on each day. However, an early typically cannot follow a night shift and you need to be cognisant of any rules about how many night shifts can be worked in row.  You now have an optimised pattern that meets the business needs whilst also being employee friendly.

HFX Imperago Workforce Design incorporates and automates the Alpha6 process reducing this process from 3-5 days to 15 minutes.