SoylentNews is people
SoylentNews
It seems obvious. You arrive at the checkouts and see one queue is much longer than the other, so you join the shorter one. But, before long, the people in the bigger line zoom past you and you've barely moved towards the exit.
When it comes to queuing, the intuitive choice is often not the fastest one. Why do queues feel like they slow down as soon as you join them? And is there a way to decide beforehand which line is really the best one to join? Mathematicians have been studying these questions for years. So can they help us spend less time waiting in line?
The intuitive strategy seems to be to join the shortest queue. After all, a short queue could indicate it has an efficient server, and a long queue could imply it has an inexperienced server or customers who need a lot of time. But generally this isn't true.
[...] Once you're in the queue, you'll want to know whether you made the right choice. For example, is your server the fastest? It is easy to observe the actual queue length and you can try to compare it to the average. This is directly related to the mean and standard deviation of the service time via something called the Pollaczek-Khinchine formula, first established in 1930. This also uses the mean inter-arrival time between customers.
Unfortunately, if you try to measure the time the first person in the queue takes to get served, you'll likely end up feeling like you chose the wrong line. This is known as Feller's paradox or the inspection paradox. Technically, this isn't an actual logical paradox but it does go against our intuition. If you start measuring the time between customers when you join a queue, it is more likely that the first customer you see will take longer than average to be served. This will make you feel like you were unlucky and chose the wrong queue.
So, before you choose a queue to join, put the screaming kids down and carefully note the average serving time in each queue, measure the queue length, and then project which will get you through to a completed transaction quickest.
(Score: 5, Insightful) by vux984 on Monday May 08 2017, @10:07PM (8 children)
There's a Mathematical Formula for Choosing the Fastest Queue ... but its useless because to use it you'd need to waste so much time measuring the queues that any time advantage is lost. And even if you do spend the time, its still a gamble because there is too much uncertainty within the small sample size of a queue that you'll still lose as often as not.
Most queues are +/- 1 in length anyway. Its pretty rare there will be 10 people in one line up and 6 in the next, unless the one with 6 has 1 guy with 4 shopping carts full of stuff or something.
In practice, queue selection is usually a function of looking at who is in the queue and who is servicing the queue. Bonus points if you shop there frequently and can assess cashiers directly rather than on broad stereotypes. But in general in my experience, evaluating queue times mathematically over the whole shift is less important than who is in the queue right now.
And that it is likely that, all things being equal, queues with more men are likely to move faster than queues with more women (men are less likely to use coupons or challenge sale prices or limits and more likely to usetc) and younger people likely move faster than older (the elderly generally seem more chatty). And avoid the trainee cashier. There's other factors... like an attractive girl with some boys queued up... maybe a boyfriend, or maybe wannabe boyfriend... that might stall the line. Or a guy with a shopping cart in it with nothing but 8 flats of bottled water in his cart -- he might take up as much space as a 'regular shopper' but he's going to move through a lot quicker. Or an elderly individual making chit-chat and reminiscing with the people in the queue... he's probably going to stall the cashier with stories too...
But you never know. All it takes is for the person ahead of you have expired yogurt in their cart, or something that wasn't priced properly...and you can't use math to predict that.
(Score: 2) by Nuke on Monday May 08 2017, @10:30PM (1 child)
queue selection is usually a function of looking at who is in the queue and who is servicing the queue
Quite. Among other things, look out for what I call "spectators", which are people in the queue merely accompanying the one doing the transactions; these peel away when they reach the front. I have seen as many as six people dissolve into a single transaction. Small children with adults are obvious examples of queue-lengthening spectators, but also look out for geriatrics accompanied by minders (who will actually do the transaction and any small groups of people chatting together.
I often go over a toll bridge with queues of cars and lorries (trucks, for the USA) at the 6 or so toll booths. Lorries can be 3-4 times physically longer than cars, but have the same transaction time. This does not seem to occur to most other car drivers and the dickheads just join the physically shortest queue.
(Score: 0) by Anonymous Coward on Tuesday May 09 2017, @01:13AM
Plus truck drivers are going to know what the fsck they're doing. When I used to drive truck and headed through Chicago on a near weekly basis, I pretty much had every toll memorized and the cash ready to go. No fishing for wallets, spare change, screaming kids in the back, etc etc. Just hand the lady (or dude) in the toll booth some bills or exact change if I had it, get the receipt to claim the expense, and go.
Of course these days all the big trucks have an I-Pass or whatever it's called for Chicago. I think they were integrating it with some other toll systems out East when I moved on from that job. Was an interesting lifestyle, definitely had its perks, but just not the career for me.
Going way off on a tangent, I still wish I could give it another go one last time before truck drivers become a thing of the past, but these days I'm one of the people automating that career away for good. Kinda sad in a way, but this pays better and I've got obligations now, etc etc. You only get to be a free-wheeling 20-something once.
(Score: 1) by Ethanol-fueled on Monday May 08 2017, @10:53PM (3 children)
Being a lazy fuck, I frequent only 2 or 3 stores -- and after many repeated instances when those lines were unacceptably long, I would inform those in line with me that management got bonuses for keeping payrolls low, and I used to work in stores, and that at any given moment there are at least 3 other employees not including the manager who were sitting in the back with their thumbs up their asses doing jack shit. Sometimes I would simply leave my groceries on the floor and walk right out, cutting off my nose to spite my face. This started having the effect of the staff calling for more checkers right as I entered the store. Not exactly the right solution to the problem, but it at least works for me.
Protip: The pharmacies and photo lab sections (and in some grocery stores the Starbucks and Juice franchises) are allowed and able to ring up groceries (other than alcohol) unrelated to their departments, though most customers are either unaware or too well-mannered to take advantage of that rule. I used to "short-circuit" waiting in the lines at a beach drug store by having the ice cream guy ring me up, since I was usually buying only 1 or 2 items nobody else got pissed off.
(Score: 2) by NewNic on Monday May 08 2017, @10:59PM (1 child)
In Target, I have used the returns counter to pay for my purchases. But never if there is a queue there, because it takes so long to process a return.
lib·er·tar·i·an·ism ˌlibərˈterēənizəm/ noun: Magical thinking that useful idiots mistake for serious political theory
(Score: 0) by Anonymous Coward on Tuesday May 09 2017, @02:28AM
Yep, I do that all the time too.
(Score: 2) by kaszz on Tuesday May 09 2017, @04:11AM
Sometimes I would simply leave my groceries on the floor and walk right out, cutting off my nose to spite my face.
It's called negative feedback loop in a language which they can interpretate ;)
(Score: 3, Insightful) by AthanasiusKircher on Monday May 08 2017, @11:04PM (1 child)
Indeed. The one thing left out of this formula and TFA's discussion, as you rightly point out, is customers. All it takes is one person with a handful of disorganized coupons, the speed of a tortoise, and a change purse which they'll go fishing for pennies in, and you might as well have gone in the queue with 3 more people in it. In that case, the median arrival time or transaction time or efficiency of the cashiers will make no difference.
Anyhow, once you make your choice, you generally just settle in. Patience is indeed a virtue, and as I grow a bit older, I find it just doesn't matter that much to get all worked up about something I can't change. I understand sometimes one is actually in a legitimate hurry over something, but most of the time, will it really ruin your day to leave the store 3 minutes later?
And IF you are the type who obsesses over the length of queues and can't stand to wait more than absolutely necessary, go at a different time. I know some people have work and family schedules that prohibit it, but frequently there are times when stores are significantly less busy. Many grocery stores seem to do little business after ~8pm, and I find it's often the most pleasant time to shop. I tend to walk fast and carry a basket rather than use a large cart when possible, mostly because I hate wasting time. During most of the day, you'll have to dodge people left and right, wait for someone to clear an aisle or wait while they puzzle for 45 seconds over what brand of pre-grated Parmesan cheese they want to buy, etc. Often one wastes a lot more time dodging people and waiting to get around them in a busy store than in the checkout line. Going on weekends is generally a very bad choice, but if one has to, Sunday evenings often seem significantly less crowded (in my experience).
I'm not saying these are universally applicable rules, and depending on your schedule, other times may work better. (E.g., Many grocery stores open at 7am or 8am, and they can often be nearly empty on weekday mornings except for employees stocking shelves.) Of course, I think many of these times are seen as inconvenient for a lot of people, who don't feel like shopping late on a weeknight or whatever. Well, then you make your choice and stand in line.
Because I choose better times to shop, I VERY rarely end up standing in line behind more than one person to checkout. So this entire discussion in TFA seems designed for a strange audience, i.e., one so deathly afraid of waiting in line that they'll stand there with a stopwatch and collect data before choosing a line, but one NOT so deathly afraid of standing in line that they'd just choose to shop at a more ideal time when there are little to no lines at all.
(Score: 2) by art guerrilla on Tuesday May 09 2017, @01:17PM
i guess this is getting into 'get off my lawn' territory, but i really resent presumptuous pukes who get in the 'express 10 items only' line with 15-20 -or more!- items...
i know it is not a big thing, but -dog damn it- i don't do that to other people, why you treat all the rest of us like it is your world and the rest of us are just clogging it up for you ? ? ? fuck inconsiderate people like that...
probably the same entitled/clueless pukes who *have* to park in front of the store (you know, where the foot wide yellow lines scream at you NOT to park), because, well, because their individual convenience far outweighs the inconvenience they are causing for every one else... again, THEY are saying 'fuck you' to me, what else do they expect me to say to them ? ? ?
can't STAND people like that; i am a loner who wishes the rest of the world would FOAD, and *I* show more consideration and respect in public for my fellow nekkid apes than so-called normies do... hypocritical fucks...