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Scientifically, You Are Likely In the Slowest Line
MojoKid writes "As you wait in the checkout line for the holidays, your observation is most likely correct. That other line is moving faster than yours. That's what Bill Hammack (the Engineer Guy), from the Department of Chemical and Biomolecular Engineering at the University of Illinois — Urbana proves in this video. Ironically, the most efficient set-up is to have one line feed into several cashiers. This is because if any one line slows because of an issue, the entry queue continues to have customers reach check-out optimally. However, this is also perceived by customers as the least efficient, psychologically."
Please, please, someone forward this to Jim Sinegal.
That ain't liver; that's beef kidney!
I thought we've verify the efficiency of single line queue for many years.
See, you have three checkout lines to choose from. You can't see the register from where you are, but at two of the three lines the cashier is a goat...
The DMV does something right? I think we need another study. :)
For all intensive purposes, "whom" is no longer a word. That begs the question, "who cares"?
That's a shame, since it's obviously the most fair, and eliminates the annoyance of jockeying into different lines to maybe get a faster one. I guess people like the chance of getting lucky occasionally, even at the cost of utility (average wait time) and fairness? Hmmm, our economy makes so much more sense now.
How is that ironic? Doesn't everyone know that? There is no customer configuration in which a single queue isn't more efficient than multiple queues, in average or worst-case waiting time or throughput. You could probably model that and prove it mathematically without needing simulation or experiments.
Watching the video, the conclusion that the video makes is "...You are likely not in the fastest line".
That does not necessarily mean that the reverse (the title) is true -- and yet they somehow jump to that conclusion with the title "...You are likely in the slowest Line."
Can we get some people who actually understand this magical thing called "logic" to start editing Slashdot?
AccountKiller
The mystery remains though why Fry's has upwards of 60 checkout registers when only 5 or 6 are open at any one time.
Negative moral value of force outweighs the positive value of good intentions.
The video actually says that, mathematically, you are likely (2 out of 3 times) not to be in the fastest line.
In his example of three lines, there is still a 2/3 chance that you are not in the slowest line. So unless "one in three" has become "likely," the headline demonstrates a failure at basic maths.
They also hide the back-scatter xray machines that assure them that you're not stealing anything. I think they only have two sets of doors at the exit way to make sure you breath out any store air you may be concealing in your lungs and have not paid for before you leave.
I don't swear off buying from places because it only hurts me, but I sure do avoid shopping at Frys because of their apparent "every customer is a criminal" mindset.
Nullius in verba
I'm sure the fact that they can have a more impressive impulse purchase rack also factors in. They can have a greater variety of items by not having the same small selection of stuff at each register.
Microcenter also does this (at least here in Denver), though it's a much smaller store than any Fry's I've ever been to (even the old ones).
Someone flopped a steamer in the gene pool.
Its because Frys wants to get a bulk discount from the register repair guy. They wait until 50 of the registers are broken, then call them.
What's this mean? Two thirds of the time at least one neighboring line will be moving faster than you, and you'll curse and stew and froth about your terrible misfortune. But look on the bright side -- two times out of three, at least one of the neighboring queues will have exactly the same burning jealousy towards your swifter, more efficient checkout.
Ironically, the most efficient set-up is to have one line feed into several cashiers.
Alanis Morissette called; she wants her misused word back. Anyway...the above statement ain't necessarily so. What putting everyone into a single queue does is ensure that the distribution of waiting times is very narrow -- everyone will spend very nearly the same amount of time in the queue before reaching a cashier. However, this setup will almost always impair overall checkout efficiency (measured in customers per hour) by some amount; the average waiting time will be slightly longer. Each time a customer clears the cash desk and the cashier has to wait for the next customer to arrive, time is lost. Since the customer can't unpack his basket while the cashier is finishing with the previous customer, time is lost. It gets worse if a customer at the head of the queue doesn't realize that a cashier is available; everyone stands around waiting that extra bit of time. Yes, this can be offset by having a staff member playing shepherd, but that's extra expense for the store (and wouldn't it be better to have that employee actually manning a cash register?). As well, the store needs to be able to maintain a larger open space by the cash registers through which people can move, to get from the head of the queue to the checkout.
In other words, the one-queue system is less efficient in terms of staff costs, less efficient in terms of average customer waiting time, and less efficient in terms of use of floor space. The only advantage is the one alluded to -- it eliminates the slow cashier/slow customer/bad luck penalty, and ensures that everyone has roughly the same wait. (And for that, I actually do prefer this system -- but I don't pretend that it's really more effiicient. I accept that I'm paying a small premium in average waiting time - and writing off a chance to ever be in a lucky fast line - to avoid the risk of occasional long waits.)
~Idarubicin
FIRST... no he dose not prove that you are in the SLOWEST line. He demonstrates that it's most likely that you are NOT IN THE FASTEST LINE. The exact same argument can be used to show that you are likely NOT IN THE SLOWEST line [of course, Slashdot editors and readers have never written any kind of mathematical proof, so the concept of "similarly" is foreign to them].
SECOND... this is elementary probability... barely even high-school level.
Given 3 lines
WLOG, randomly choose one
there is 1/3 probability that your line is the fastest
therefore there is 2/3 probability that your line is not fastest
therefore it is more likely that you are not in the fastest line
THIRD... there is nothing ironic about the single queue being fastest. This is obvious to anyone who has even set next to someone who's brother's dog licked someone who accidentally clicked on the wiki page for queuing theory.
I cannot believe that this drivel got posted. Apparently, Slashdot is now for remedial math. AND the poster (and editors) didn't even get it right! Slashdot editors fail remedial math.
I know this site went to shit about 7 or 8 years ago, but all nerd cred is forever lost in my eyes. It is now just for 12 year old mouth breathers who have no idea what they are talking about.
Logging into my account that I created when I officially gave up on this website. I am not going back to routing *.slashdot.org to 0.0.0.0 so that I am never tempted to return here on a lark.
If you have 3 lines, you'd think that 2/3rds of the time there's another line which moves faster. But if you're in a slower line, you're spending more time in that line. So with three lines, you're only in the fastest line for 1/3rd of your purchases. But you're in the fastest line less than 1/3rd of the time. The way Fry's does it with a single queue is pretty much the best way (I can think of an exception for those 10 items or fewer lines).
An even better example of efficiency is a roller coaster. Typically one or two queues all the way to the loading platform, where people are then directed to very short queues for each row of seats. Substitute checkout lanes for the row of seats, and you have a very efficient system.
make imaginary.friends COUNT=100 VISIBLE=false
between single-line multi-server queue and multiple queues.
This occurs in fast food restaurants with the row of cashiers.
This is because some people are "blind" to the fact that there is a single line
situation in effect. These people can be divided into:
1. The generally oblivious. Mindless automatons or cellphone talkers.
2. The socially clueless. Somewhere on the autism spectrum, they don't
understand that queuing is a complex social interaction with rules and etiquette.
3. The obnoxious. Sees the situation but overtly butts in front to stand in front
of one of the cashiers directly, thus forcing others to break rank and sneak in
behind him, since the discipline is shot.
4. The "will be first up against the wall when the revolution comes" devious, who
form their own line like #3 but do it by carefully assessing the situation then actively
pretending that they are in category 1.
So it goes to multiple queues for a while, then some opportunist realizes they
can line up ambiguously in between two cashiers to snag whichever comes open
first, and we're back to single-line til a type 1 to 4 person arrives.
Where are we going and why are we in a handbasket?
"Right now, there're hundreds of
different languages being spoken around the world - you think one more is going to destroy communication forever?"
Where are we going and why are we in a handbasket?
The poor register jockeys making a flat hourly rate no matter how many customers get through their lines. The harder they work, the more work they make for themselves, particularly if they're sharing all the customers. (Anyone who's worked in any sort of real job surrounded by slackers knows this.) At least with your own customer queue, you can kind of see an incentive to get them all through, even if more keep showing up. As an added bonus, a manager might notice the ten people waiting to get through the lazy bitch's line (although in my experience, that just results in the efficient one being told he's "not taking initiative" or some similar bullshit.)
MSIE: The world's most standards-complaint web browser.
That 2 out of 3 times - I'm in a faster line than you. Ha!
Also, 6 out of 8 times, my cashier is more competent and better looking.
Mit der Dummheit kämpfen Götter selbst vergebens
On average, and entirely unsurprisingly, one time in three you'll be in the fastest line; one time in three, you'll be in the slowest line. (And in the remaining third of cases, you'll fall in the middle.)
Don't give me any of that "It's how you play the game" positivist commie-pinko crap.
*I* must win, and everyone else MUST lose. Regardless if it is fastest cashier line or thermonuclear war.
Any other solution is simply unacceptable injustice and it makes baby Jesus cry.
Mit der Dummheit kämpfen Götter selbst vergebens
The problem most people see with a single queue is that the line is LONG. Our minds have issues thinking of the fact that 4 lines with 4 people waiting each is the same as one line with 16 people waiting. We also give up the illusion of choice with the longer line. With multiple lines, we
can look at the quantity of products in the baskets, the perceived speed of the cashier, if there's a second employee at that register helping to bag groceries, etc. Of course, none of that matters if one of the people you're stuck behind is trying to pay with food stamps and has selected the wrong size of product, and needs to run back quickly to exchange it with the correct size.... or if someone's check won't read, or whatnot.
The other issue with a longer line is that you need space for it. Fry's is set up to handle the long queues, but look how much space that whole arrangement takes up, not to mention the fact that people at fry's don't tend to purchase 100 small items, which fascilitate the need for a conveyor belt and bagging system. The grocery store probably couldn't get away with much less space for the registers than they're already using, so providing space for a long queue would require them to take in more of the store for that purpose. Best they can do easily is provide the express lanes (which would work even faster if they only accepted cash).
-Restil
Play with my webcams and lights here
The Post Office & the Bank lines work this way (where I live), and nobody seems to complain that it feels slower. I think if supermarkets designed for it, it wouldn't take long for (most) people to be accept it.
They're not going to stop you from coming in. I've shopped at Fry's and Best Buy on many occasions, and each time I've walked passed the door Nazis without saying a word. They didn't try to stop me (that would be illegal), nor did they ever take my photo, ID, or "blacklist" me from entering.
The only exceptions are club stores like Costco where you sign a contract that says they'll revoke your membership if you don't let them check your receipts.
There's no -1 for "I don't get it."
What if you're in India and there's no line at all?
This would have been the first post, but I was on the slowest connection.
i pick the line with fewest women in them because they always seem to want to write a check and don't start pulling the checkbook out of their purses until after all items have been scanned... don't want to be sexist but there it is
Don't we all learn in school why 1 line is faster? I sure did. Not to mention that any place where it really matters (e.g. airports) do this already. Who cares what a handful of people who didn't pay attention in school "feel" about it "psychologically". What about me? Do you have any idea how distressed I get when there's multiple lines to choose from? And no way to know for sure which line performs best?
While we're on the subject, I notice further down people commenting on the new self service check outs that many retailers are starting to put in. They seem to like them. I LOATHE them. In my area, only Canadian Tire and Wal-Mart use them and I avoid them. Certain days through the week, at Canadian Tire only the customer service desk and the self serve checkouts are staffed. I always go to the customer service desk when that happens.
1) The self serve check outs are bar code and scale based. The system has to know the precise weight of every bar coded item. If you don't put the item on the scales, it won't let you continue, yet the scales are imprecise enough that a two back of automotive bulbs often don't weight enough to register. And good luck trying to deal with an unwieldy item that doesn't fit in a standard bag. A regular clerk just throws a sticker on it and moves on. This self service system halts and you have to wait for the central cashier to come over and fix it. This always takes a lot longer than having a clerk already standing there and eager to get to the next customer.
2) The system does not provide a customer a way to manual type in a barcode number the way a skilled clerk can when the bars themselves aren't legible to the laser. At the Walmart, deli items get a custom bar code printed up right then and there, but for some reason, the ink sometimes gets a tad smeared. (I don't know what ink/printing system is in the one they use here.) A human can read the numbers, but the laser can't apparently make heads or tails of the bars. Again, you need that central cash person to come over and fix it.
3) Both self service systems are set up so one person is supervising 4 registers and it seems at least at the Canadian Tire, the management only allots one person to do this per shift. At the Walmart, it appears that during slack time, the customer service person covers it in addition to their other duties. These leads to a problem. If you have four clerks and things are slow, you have the flexibility to send one or two off on break earlier or go stock shelves or something. When it's only one person, sure it's cheaper, but what happens when that person needs to go take a leak? At both Walmart and Canadian Tire on at least one occasion each, there hasn't been anyone standing on that little raised platform next to the self serve checkouts. At the Walmart at least, there was usually two other cashiers on duty. (one at the one queue into multiple registers section and one in the traditional single queue area) At Canadian Tire on the other hand, one time there was nobody, I mean nobody at any of the registers, including the customer service. I looked around, waited a bit and then the customer service staff came back with an empty cart (had been restocking returns I guess) and the self serve supervisor came hustling over from the bathroom/service centre area looking flustered.
I need a wheelchair van for my son. Help me get the word out. https://www.gofundme.com/wheelchair-van-for-jj
What if you're in India and there's no line at all? Just a huge mass of people crowding against the service counter shouting for what they want, over and over till the clerk serves them.
Substitute "India" for "London" and "service counter" for "bar in a busy pub on a Saturday night" and this remains true.
catch (HumourFailureException e) { e.user.send("You, sir, are a humourless idiot."); }
. Ironically, the most efficient set-up is to have one line feed into several cashiers.
Since irony indicates a result the opposite of what you'd expect, and logic tells us that the one-line option is the most efficient... how's it ironic?
No, it's just people being idiots. It doesn't work as sarcasm. "I couldn't care more" would work as sarcasm.
which is totally what she said