What happens when you add a new teller? (2008)
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What happens when you add a new teller? (2008)
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Re: What happens when you add a new teller? (2008)
#2A thread from 2015: https://news.ycombinator.com/item?id=9652882
Re: What happens when you add a new teller? (2008)
#3The teller post and queueing theory ideas are included here: https://github.com/joelparkerhenderson/queueing_theory
Re: What happens when you add a new teller? (2008)
#4Why I will never live anywhere with roommates, or have an event, anywhere with one bathroom!
Re: What happens when you add a new teller? (2008)
#5Seems to me the big problem with any kind of retail queue is highly inconsistent service times. If you have a consistent time/ customer, it's easy to predict. As soon as you have some customers taking 20 minutes and some taking 2 minutes all the simple math goes out the window. This is why some people get so infuriated when they see the person in the front of the line break out a fist full of coupons, food stamps, or wants to pay with a check. It's also why so many businesses use a single queue with multiple tellers/ cashiers.
Re: What happens when you add a new teller? (2008)
#6Seems to me the big problem with any kind of retail queue is highly inconsistent service times. If you have a consistent time/ customer, it's easy to predict. As soon as you have some customers taking 20 minutes and some taking 2 minutes all the simple math goes out the window. This is why some people get so infuriated when they see the person in the front of the line break out a fist full of coupons, food stamps, or…
"Seems to me the big problem with any kind of retail queue is highly inconsistent service times."
The article mentions that as one of the two problems: "If customer arrivals were exactly evenly spaced and each took exactly 10 minutes to serve, there would be no problem."
"It's also why so many businesses use a single queue with multiple tellers/ cashiers."
The article implicitly assumes a single queue. But, as long as any empty queue is immediately filled by someone switching from another queue, this assumption doesn't affect the expected total # of people waiting.
Re: What happens when you add a new teller? (2008)
#7It's all fun and games until it's not a bank with one teller, but a LabCorp with one phlebotomist, and you're not there to give a blood sample, but a urine sample.
Re: What happens when you add a new teller? (2008)
#8Kind of a textbook description of queue theory if you were taking a stochastic processes class. If the author really is suggesting this for use in retail line situations, he is out of touch because... retail managers have no idea what queue theory is. If they did, they would be making much more money, and not working in retail. Staffing is more of a function of how many people you can get on the clock without getting yelled at by regional managers (who also do not know queue theory) for overstaffing.
Re: What happens when you add a new teller? (2008)
#9Did a fun project for my MBA. A bike parking facility downtown, where you can park your bike securely, showers, lockers, towel service, ironing boards, buy some coffee and a snack. Raised $80k for it...needed 100. Anyways
We modeled the showering process. Had some data on how long people took to shower. Needed something like 3 showers per gender to get good throughput
One of the MBA profs didn't like this for some reason. Didn't believe it would be enough (without any numbers to back it up). We were like, well if we add a fourth shower we can accommodate dozens of more people. He liked that even less
Re: What happens when you add a new teller? (2008)
#10What does it mean that service times are exponential?