Workforce schedule optimization is not compromization

Richard Mills CEO    Schedule24 Workflow Management, Shift Patterns, Workforce Factors    

One of the inputs we spend some time is demonstrating just how big a problem optimizing a workforce schedule is. In fact it is such a big problem and so expensive to achieve, examples are very hard to find – except for the most trivial scheduling problem. So why does everybody seem to offer this as a standard feature in workforce scheduling. Well in the main it is just a lazy use of marketing words. It sounds compelling, exciting and you know ‘you only get what you pay for’. That’s why you need very deep pockets, and a great deal of time on your hands to have a better than even chance to achieve that optimized workforce schedule.

An optimized schedule is the best possible solution available. First you need know all the factors that will define the pathways to be optimized to reach a defined goal. The more factors the bigger the problem to be solved. Even a handful of factors can generate a problem space that is measured in orders of magnitude. Put another way, defining the optimization model can be harder than doing the scheduling in the first place. Second, because there may be more than one solution you need to know all the solutions that are possible. These kinds of problem can take a very large computer a very long time to do this.

Another problem is we may decide what an optimum model is for staff headcounts and how they are distributed over a time range. Alternatively there may be a series of desirable goals for a staff day-on day-off working pattern. As more constraints are added the problem becomes easier to work out but the net result is what we considered optimum for one category is ruled out as new constraints for another category of information is added.

For example, the following goals ‘had to be’ achieved for a clients workforce deployment strategy. Not because they were desirable, but they had negotiated and signed off union contracts before realizing whether it was even possible:

• between 4 and 6 consecutive work days
• between2 and 3 consecutive rest days
• an exact number of days off in a pay period
• one weekend off and one weekend working in 4
• and at least one weekend day off in 3
• reduced staff at weekends

This occupied an HR team for a period a little over 7 months with no result. Using an intelligent agent designed to understand among other things the problem space of weeks in the context of week days and weekends completed the problem in 35 minutes. Out of a problem space of unknown size 4,712 candidates were identified as possible solutions. Only 13 of those solutions succeeded for further consideration.

Contraint scheduling can be contrasted with heuristic scheduling which promises to provide very good solutions most of the time. And a lot quicker and a lot more cheaply but that can be discussed another day.

Two things in conclusion.

• Don’t agree to something you don’t understand in the context of workforce schedules, you will invariably underestimate the problem; and
• When it comes optimization you probably are not getting what you pay for.

For more information about you staff deployment strategies contact Group Senior, Workforce Scheduding at Intellicate

When it come to workforce scheduling flexibility should not mean confusion.

Richard Mills CEO    Intellicate Solutions, Schedule24 Workflow Management, Shift Patterns, Workforce Factors    

I often get asked the question what is it about scheduling that makes it so hard. I always answer Workflow! That more than anything is what defines good staff scheduling from bad. One problem is the format and publishing of schedules is often similar e.g. staff down the left and dates across the top – with perhaps some frequency counts at the bottom. This almost universal format is efficient, conveys a lot of information and is generally understood just by looking at it. That is why formatted spreadsheets and most staff scheduling software appear to do the same job.

However the effort and time to achieve something as familiar as the workplace schedule can be as different as ‘chalk and cheese’. It is workflow that makes the difference in the quality of workforce scheduling. If someone told you they had a ’system’ that was totally flexible, gave you complete control to do what you wanted, and above all cheap – even free – most jump at it. That’s exactly what a spreadsheet offers. However there is nothing stopping you doing something dumb. In fact you can even make a staff schedule that can’t possibly succeed look good – until someone else, usually operations, use it.

If all you are bothered about is just getting something out, and ultimately it’s someone else’s problem on the day (so much the better), that might be OK for some managers – though in a business serious about operating costs they are not managers for long.

The relationship between staff hours, costs and timing of shift patterns allied to a business requirement is complex. Without workflow you are unlikely to arrive at a satisfactory solution. Worst of all you are destined to deliver different workforce scheduling outcomes even when the problem remains the same. With workflow you get flexibility, without it you get confusion.