Apparently, there is a science to choosing the fastest checkout lane at the grocery store. I’m going to be trying this one.
Each person in a grocery store checkout lane approximates 48 seconds in addition to whatever is in his/her cart (this average time includes exchanged greetings and the payment process). Each item in a cart is only 2.8 seconds. Therefore, 17 items in someone’s cart is the same as an extra person. So, it is usually better to hop in line behind the one woman with 30 items (132 seconds) instead of the three-person Express Lane (which will be between 153 and 270 seconds).
This assumes clerks are similarly fast (not a rule where I shop). Also, it doesn’t say anything about those U-Scan self-checkout machines. I’d love to know how to spot the clueless before I stupidly park my cart behind them.
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The queue system used at supermarkets is mathematically-speaking extremally unfair and unpredictable. I’ve studied queue theory – I’m trained in networking, it’s something we need to know. The optimal queueing stratagy is common-queue. The fact that supermarkets don’t use this is down to a matter of pure practicality: To physically impliment a common-queue system would require a prohibitative amount of floor space. It’d also be more prone to confusion caused by children running around, people running back to pick up an item they forgot, and so on.
You know what doesn’t make sense about the express lane? The supermarket rewards their least valuable customers with their own lane. What’s that all about?
I’m totally on board with Siricou’s idea. That absolutely make the most sense if it could be implemented.
The designation of an express lane doesn’t actually improve throughput over just making it a non-express lane. Not does it lower the average waiting time. It’s purpose is to improve consistancy – to make everyone wait for a reasonable time, rather than have some people wait a very short time and others a very long time. Express customers screw up the distribution of the main queues, as they are effectively illusionary time-consumers.
And… there goes my laptop. Goodbuy, £600 for a replacement. I was hopeing it’d last another month or two, but the power input finally packed in while I was typing. Been going for weeks. On batteries now. And no, it’s not the charger.
Although sexist, middle age men shopping alone are absolute race cars through the check out. They don’t like to shop, they have their list and just want to get in and get out. No chit chat with the check out clerk, they will have their bags packed efficiently and quickly and with a wallet rather than a purse the size of a small city, payment is also quick. I would take a line with 3 or 4 or these guys holding 10 items each rather than a single matron with a dozen oranges!