Asynchronous channels – alternative formula for long-term forecasting

As part of our university reading we have come across a very interesting book written by Koole, called “Call Centre Optimization”.  Recently, during the delivery of our Planning for Back Office training we used this formula for a discussion as a possible back office alternative to Erlang-C and a way of factoring in variability and confidence.

This could be useful for long-term planning and budgeting; however with this considered it could really support the real-time and operational planning.

Variability of the amount of asynchronous work

“The amount of work from asynchronous channels is variable: both the number of contacts is variable and their handling times.  Because of the nature of the asynchronous contacts it is of interest to compute the standard deviation of the total amount of work in a day or a period of the day.  There is a mathematical formula to compute this.  Assuming that the forecast is good and that the only variability in the number of arrivals comes from Poisson distribution, and that the variability in handling times is roughly of the same size as the handling times themselves (which is a reasonable assumption), then it is safe to schedule (Volume+1.4 √Volume) x AHT instead of just Volume x AHT.  Under the assumption this gives roughly a 84% probability that all work can be done.  If 1.4 is replaced by 2.3 then this probability is 95%.”
Koole, Page 104, “Call Centre Optimization”

What flexibility is being built into your long-term plan?

How could this formula help your real-time & operational management?

To watch the National best practice seminar video click here, or to read the session write up and watch the slides click here.

Phil Anderson,
Contact Centre Specialist,
Professional Planning Forum
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