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[jahillia]

trying to explain erlang to my boss...

He sees we have 58 agents on the phone for an hour and they should be able to take 580 calls if they average 6 minutes talk time....

ErlangC says the most we can take is 460.

He wants to know why the difference...how can I explain this to him?

[n_meghanath]

hmmmm!!!

It seems he hasn't gone beyond the unitary method, anyways ask him to send 58 calls together in one go every 6 mins and make sure that your agents spend exactly 6 mins on each of this calls so that you could hit 580 with no idle time for the agent to breath between the calls.

Calls arrival pattern is something you should try to explain rather than getting into lamda, poison distribution etc. For the sake of shortning the explaination you may even bring in the occupancy factor of 80% on the workload hours generated by 58 agents in 1 hr which would translate into around 460 calls.

If he says 80% is less productive than you can ask him to take a walk.

Meghanath

[Bay Bridge Brian]

There are other ways to go about finding ASA, Abondon Rate, Occupancy, and many other factors without using Erlang. The problem with Erlang is that it consistantly overstaffs costing the company money that could be used else where. I would be more than happy to discuss more effective solutions with you and your boss.
Drop me a line at bjs@baybridgetech.com to go over the alternative solutions to the problems that you are facing.

Brian

[NBosch]

I agree with Meganath fully and think the best way to explain it, is the call pattern.
Calls don't come in in a neat fashion every 6 minutes to suit the agents. Also, AHT is basically summed up by the first letter: the A for Average. Meaning that agents will not answer every call within 6 minutes.

Another good point is occupancy off course, as agents will not be "operational" for the full 100%. I do think however, that based on the time span of 1 hour, an 80% occupancy is quite low. This should be a daily goal, not an hourly. And if your team leaders are on the ball, they should be able to have this significanly higher at certain time intervalls .... and lower at others.

Good luck with handling your boss.

[thetuan]

Jahillia,

Let me give you a way to explain this to a non call center person. All the replies in this thread are correct, but I don't think the explanations are simple enough for a "person on the street" to understand.

Simply put, call arrival patterns are never linear so the operators are never taking calls at a constant rate in any given hour. If this was a production shop and the work load is predictable, then it is linear and you can predict, without regression analysis, the ouput of the operator.

So why the output for the operator will go from 580 calls down to 460 calls? You will have shrinkage time for the operator during the hour. One part of skrinkage time is time when the operator is not taking calls. Niek alluded to this but to explain this further, the operator will have "downtime" during the hour when he/she is not talking to customers. You can easily have your boss observe this fact by just walking around the call center. The job of the call center mgmt is to minimize this "downtime" to a reasonable factor that works for both the company and the operators. So be ready to explain to your boss what percent of the hour is the shrinkage time for the operation and what makes up the shrinkage time.

Any reasonable person will understand this and will be better informed when he/she looks at service levels and number of calls taken.

Tuan

[Charles Alvear]

All of these responses are defintely sensible for anyone with a call center background.

As just about everyone has touched on, the unpredictability of the call patterns is the key to the response to your boss.

You might simply reply back to him and ask if he will send out a memo to all 560 customers who are expecting to call each hour to notify them that they must call in at an assigned time slot and their time limit with the agent is going to be 6 minutes, no longer. He should do this for every hour of your workday. That might help him understand the call patterns issue.

If he is able to pull this off, then have him remove all projects off your plate so you can solely focus on micromanaging your agents to drive up their occupany rate to 100%. This will kill morale on the team and will probably result in some employee turnover, so be prepared for the ensuing costs associated with recruiting and hiring new talent.

Hope this layman explanation helps you with your situation.

[sheldonoverton]

In a perfect world, yes, that would be the case. But as you know, in the call center, the world is far from perfect.

He's assuming that agents will be on the phone 100% of the time during that hour. It would be nice if agents never needed a restroom break or a sip of water, and were at their desk every second they were scheduled to be, but that's not realistic. It's more realistic to assume 80%-85% of the time.

I hope this helps.

Sheldon Overton
sheldonoverton@aol.com

[Kevinized]

To explain an erlang formulas, show it to him.
Explain what the variables are

the total traffic offered in units of erlangs
the number of agents
the probability that a customer has to wait for service

The traffic is measured in number of calls offered, time offered and call lengths.

Now even with an understanding pure erlang formulas, there needs to be a system that will pass the calls free of any delays but when calls are routed through the various subsystems, PBX to auto attendant to ACD, delays are introduced in the calls by the transfer process and if there are not enough ports on the systems, more time can be introduced waiting for a port to become available.

Rather than expect agents to perform to some arbitrary standard, Measure their performance to see where it is compared to their peers. When you identify the better performers, encourage and enlighten the poorer performers to how the better ones do it.

If you can set aside time for the poorer performers to monitor the better,
they will see how to improve themselves.

Kevin.MacLean@myownsystems.com

[Daniel Rock]

It is also important to consider Quality vs Quantity. Of course you can try to answer to the maximum amount of calls, but sometimes clients require special attention, keep talking or request almost impossible solutions therefore the Agent has to spend more time on the phone either to calm them down or explain the situation. The agent cannot hang up with a client every 6 minutes just to keep the perfect amount of calls. In addition, an agent could be more than 15 minutes sometimes waiting for calls.
The only explanation I see for a Boss to say something as ridiculous as that is to encourage faster work, by giving an impossible target that the employee will feel that he has to achieve.