[HN Gopher] Where to wait for an elevator (2010)
___________________________________________________________________
Where to wait for an elevator (2010)
Author : bumbledraven
Score : 66 points
Date : 2022-07-06 17:07 UTC (5 hours ago)
(HTM) web link (www.johndcook.com)
(TXT) w3m dump (www.johndcook.com)
| baxtr wrote:
| Might be a bit off-topic...
|
| But: The one big question I have with elevator UX is this: why
| isn't it possible to deselect a choice? So pressed 10th floor but
| wanted 11th. There is no way to press button 10 and then button
| 11 to correct that mistake.
|
| Will I ever solve this mystery?
| thefifthsetpin wrote:
| Some elevators are clever enough to detect kids messing with
| them. If you select enough floors, they'll just deselect
| everything soon, including your errant selection.
|
| Admittedly, that's not very helpful unless you somehow knew
| that the elevator you were in had been configured in such a
| way.
| rootusrootus wrote:
| I imagine that's by design. Otherwise you could unselect other
| people's choices.
| baxtr wrote:
| Yes of course it's by design. I just wonder why.
| samatman wrote:
| Maybe ask a woman?
| dejj wrote:
| In Marc-Uwe Kling's "Qualityland", reversing elevators,
| turning around subway cars, and flicking traffic lights is
| a level-skill obtained by accumulating social credit
| points.
|
| [1] https://www.amazon.com/Qualityland-Visit-Tomorrow-Marc-
| Uwe-K...
| mulmen wrote:
| Because you could deselect other peoples choices.
| eddd-ddde wrote:
| This isn't an argument, as you can also select other
| people's non-choices.
| [deleted]
| halfnormalform wrote:
| Elevators sometimes have an anti-mischief feature where
| they will deselect every floor if all the floors are
| selected in a brief period of time. The cab will slow to
| a stop if no new buttons are pressed. It's kind of eerie,
| actually.
| mulmen wrote:
| Neat! How do you know this?
| halfnormalform wrote:
| The elevators at my office were upgraded a few years ago
| and one of the elevator techs happened to mention it to
| me. I tried it out while alone, for obvious reasons.
| mulmen wrote:
| Cool. I was hoping for something other than "I
| exhaustively test all new elevators".
| rootusrootus wrote:
| There's some incentive not to do that, however, because
| in many cases it will inconvenience you just as much as
| everyone else. But if you could just deselect all the
| floors between the current one and your destination,
| there's a pretty strong incentive there.
|
| Until someone punches you out, of course, because it'd be
| hard to hide and you're in a confined space with them...
| rahimnathwani wrote:
| That doesn't prevent people from getting to their
| destination.
| ehvatum wrote:
| How do I go about deselecting other people's choices, if
| that's my specific goal? I can get whatever I want in
| Jira, but nothing in elevators. It's fucked.
| [deleted]
| jaywalk wrote:
| Not worth complicating the UX to address such a minor
| issue.
| baxtr wrote:
| Minor to you... Introducing a great experience is the job
| of good UX. Not simply limiting options and saying
| 'done'. I am sure there are better options to handle
| this. Seems like no-one has put the effort into it (yet).
| [deleted]
| jaywalk wrote:
| Unnecessarily stopping at a floor for a few seconds is
| minor to literally everyone riding in a public elevator.
|
| But yeah, I'm sure that at all of the various elevator
| companies, over all of the years that elevators have had
| electronic controls, nobody has bothered to put any
| thought into this.
| allenu wrote:
| This is it exactly. It opens up the door to even more
| complexity in the design...
|
| Now that you can unselect floors, if the elevator is on
| its way to the 5th floor and you unselect it, should it
| skip that floor mid-movement?
|
| If there's only one floor selected, we'll probably want
| to disallow unselecting it while the elevator is moving,
| but what if you just hopped on and it hasn't moved yet?
|
| This would probably make for an interesting interview
| question.
| asmosoinio wrote:
| In the Philippines (tested in Manila) high rises this seemed to
| be a common feature: Double clicking a selected floor would
| deselect.
| NovemberWhiskey wrote:
| Elevators in Japan often support this; usually either a double-
| tap or press-and-hold the button to deselect.
| butterNaN wrote:
| I have been to a few elevators in India where you can deselect
| a choice like you described. However they are not rare.
| layer8 wrote:
| There are two cases where deselecting a floor would complicate
| the logic:
|
| 1. When the currently targeted floor is deselected and the
| remaining selected floors are all in the other direction: Then
| the elevator would have to either reverse course without
| stopping -- a situation which otherwise doesn't occur and would
| be unexpected and possibly dangerous for the passengers -- or
| stop on a non-selected floor before changing direction, which
| would be confusing as well.
|
| 2. The deselected floor was the only selected floor: The
| elevator would then have to choose a floor to stop on by itself
| -- e.g. the next one it can safely stop on -- which is also a
| situation that doesn't otherwise occur. In addition,
| deselecting the only selected floor doesn't seem to be a
| practical use case.
|
| So instead of having to define, implement and test a behavior
| for those odd situations, it's safer and less costly to just
| disallow deselection.
| xmodem wrote:
| Rather than testing these scenarios, couldn't one simply
| just(tm) not allow deselection in these scenarios?
| layer8 wrote:
| Then you'd have to test _that_. And it would still be
| confusing to users that deselecting only sometimes works.
| bobthepanda wrote:
| Right.
|
| HN is not representative of the average person, or even a
| standard cross section of society. A elevator has to be
| legible to an 8 year old child, an 80 year old retiree,
| someone who is blind, a person who is deaf, etc.
|
| When designing for such a broad audience, KISS (keep it
| simple, stupid)
| deathanatos wrote:
| I didn't think elevators permitted scenario 1 to occur at
| all; I thought they refused to allow selecting floors not in
| the direction of travel.
|
| (I don't usually board elevators traveling in the wrong
| direction, ofc., so, I'm not that sure.)
| zerocrates wrote:
| I haven't done it in a while but my recollection is that if
| you press a "wrong-direction" floor it will just go there
| after having completed all the previously-selected stops.
| scrumbledober wrote:
| not just previously selected but it will wait until there
| are no stops in the current direction, then switch
| directions and go in the reverse order
| zerocrates wrote:
| Yeah I wasn't sure what will happen if more people add in
| stops in the "right" direction afterwards, I don't think
| I've ever been in that situation, but that makes sense.
| spogbiper wrote:
| The one in my building will allow you to select any floor
| at any time. it always goes to the last stop in the current
| direction before reversing as far as i have noticed
| [deleted]
| hahnchen wrote:
| If I were to guess, people enter the elevator and
| subconsciously just press which floor they want to go to. If
| you allow deselecting, someone will inadvertently deselect
| where they want to go to if that button is already selected.
| pflenker wrote:
| Because in a busy environment (where consistently more than one
| person uses the elevator) the scenario of making a wrong
| decision and having the wish to correct it occurs far less than
| the scenario where someone does not pay attention to which
| floors have been selected already and deselects your
| destination. At the worst case this means that you both miss
| your stop because you both did not notice.
| baxtr wrote:
| Yes, some elevator environments are busy. But many aren't.
| alephxyz wrote:
| Might also get confusing if the LED indicating the button's
| been pressed stops working
| Swenrekcah wrote:
| This comment right here is an example of thinking like a
| good designer. No amount of sleek surfaces and cool
| lighting can beat this.
| h4waii wrote:
| Leave the button recessed after it's been selected, even
| if the LED fails (how often does this actually happen?)
| it's still a visual and tactile indicator.
|
| To deselect the floor, simply press in again.
| mellavora wrote:
| So why is it that if you select 2 and 3 you don't get to floor 5?
| vidanay wrote:
| You mean 6?
| mikkergp wrote:
| I mean 8
| OisinMoran wrote:
| "Since you can't move without increasing the average distance,
| you must have started at the best spot."
|
| Technically this isn't a fully sound inference. All this proves
| is that you're at a _local_ optimum. So you 'd also need to know
| or show that there is only one optimum/the problem is
| convex/local=global or any variant.
|
| Of course that _is_ the case here, but it 's always worth noting
| the specific properties of a problem that make a neat solution
| possible.
| glitcher wrote:
| The best real-world optimization: stand aside to make room for
| anyone exiting the elevator before crowding the doorway trying to
| walk in too quickly!
| novosel wrote:
| Oh my god, this.
| acomjean wrote:
| clearly they aren't using "destination dispatch" where the
| elevator tells you where to wait after you tell it where you want
| to go.
|
| https://en.wikipedia.org/wiki/Destination_dispatch
|
| I've only seen this in one building. It was a little weird, but
| it supposedly is coming soon to more and more elevators.
| tarentel wrote:
| I worked in a building at NYC that did this. It was confusing
| at first as I just immediately jumped into the first elevator
| door that opened since it was my first day and didn't realize
| there were no buttons inside. After the initial and very short
| learning curve due to all the stairs I had to climb that day I
| would say it was much more efficient than any other building I
| had been in.
| bombcar wrote:
| I encountered one that did this, but the screen for selecting
| your floor was a temperamental touch screen, so trying to
| type "13" would often select "1" and "11" before 13,
| consigning you to riding and stopping at those floors, also.
|
| Then I found the secret wheel-chair button assortment, which
| was genuine buttons.
| yccs27 wrote:
| If you want a fun challenge, try making your own elevator
| algorithm! https://play.elevatorsaga.com/
| jaywalk wrote:
| I stayed at a hotel that used this. It's a very nice, efficient
| system. Much better than everybody cramming into the next
| elevator that arrives and selecting a bunch of floors.
| bobbylarrybobby wrote:
| At the end of the workday, not having several full elevators
| stop on their way down to the lobby to try (and fail) to take
| you down from the second floor is a godsend to everyone
| involved.
| ncmncm wrote:
| 2nd floor? You need the exercise.
| ThePadawan wrote:
| I live in a building that has this. As a resident - it works.
|
| Whoever made this building made a whole lot of mistakes though:
|
| - They put this into a building with public spaces (e.g. a
| doctor's office).
|
| - When standing in front of the elevators, nowhere does it say
| which office is on which floor (it says so in the lobby which
| you walked by to get to the elevators)
|
| - The screens where riders have to select floors automatically
| turn off after not being used for a few minutes. At that point,
| to people who have never used them before, they do not look
| like they have anything to do with the elevators at all.
|
| - When these screens do turn on, they list the floors in
| reverse order (i.e. highest first). That makes sense because
| the people on the highest floors are the most likely to use the
| elevators, right? Well, all the offices are on floors 1 through
| 4. They're on page two of the screen. The button for "next
| page" is not labelled as such. You have to know it's there.
|
| - The screens are resistive touch screens and not well
| calibrated. The buttons to select a floor are approximately the
| same height as the tip of your index finger. A first time user
| won't hit the correct floor the first time, guaranteed.
|
| - At the point where you are standing in front of the
| elevators, you are so deep into the building that you have 0
| cell reception. I have randomly encountered food delivery
| people be stranded there because they could not call their
| customers to figure out how to use the elevator.
|
| Every single week I have to rescue a poor 80 year old person
| who needs to go to the doctor and is horribly lost and
| confused, and it just breaks my heart how the building's owner
| (which I've contacted about this to no avail) chose "oh the
| salesperson said this was more efficient and trendy" and now a
| large percentage of users are so much worse off for that
| choice.
| ehvatum wrote:
| I wonder if there is any improving that system without
| replacing it.
| xmodem wrote:
| Most of the problem described here is the input mechanism.
| The building I work in has "destination dispatch" too but
| instead of a touchscreen, it has a large numeric keypad
| that you type your floor number on, with physical buttons
| that look like normal elevator buttons. We do also have
| some floors that are open to the public and i've only seen
| people confused by it a couple of times in several years of
| working here.
| ThePadawan wrote:
| There are some easy fixes to the things I described - like
| adding a list of offices and floor numbers above the
| touchpads, or adding a phone signal boosting indoors
| antenna.
|
| Apart from that, the first thing I wondered when I moved in
| was "oh, as a resident, does that mean I just get a keyfob
| I can wave at this screen that knows I live on the X-th
| floor?". That's also feasible, to the degree that the
| Wikipedia article linked above refers to this.
|
| The problem with all these fixes is of course that they all
| cost more than $0.
|
| And neither the company owning this building nor any
| landlord company involved in its operation is even based in
| the same ZIP code as the building. So why would they care?
| 8organicbits wrote:
| > So why would [the landlord] care?
|
| A complaint from one of many residents may be futile, but
| a complaint from the retail tenant with the largest space
| would carry more weight. Surely showing that this
| elevator decreases the value of their building would be
| something they'd care about, if delivered correctly.
| chis wrote:
| Is there any intuitive explanation for why the mean minimizes the
| squared error? I know it IS true - this property is used for
| linear regressions etc - but I couldn't actually explain it.
|
| It seems like whatever minimizes a squared error should itself
| have some squares in it.
| shikoba wrote:
| If you know about inertia, the grabiy center is where inertia
| is minimized. But it's just a way to rephrase it.
| xcskier56 wrote:
| Whelp, now I'm gonna think about minimizing the distance to every
| elevator every time I'm in front of more than 2 elevators...
| thanks
| kazinator wrote:
| > _So standing in front of the second elevator minimizes the
| expected distance to the next elevator, assuming all three
| elevators are equally likely to arrive next._
|
| > _What if you want to minimize the worst case instead of the
| average case? Stand half way between the first and third
| elevators._
|
| What is the difference between "in front of second" and "halfway
| between first and third"?
| troglonoid wrote:
| In the first paragraph he says the elevators aren't evenly
| spaced, and then again, it is mentioned in the James Hadley
| quote.
|
| In this scenario, the second elevator isn't centered between
| the first and the third elevators.
|
| If I understand the description properly, the layout may be
| something like this:
|
| []__[]____[]
| sanderjd wrote:
| The elevators are not evenly spaced. This point is in the
| article but could have been belabored a bit more. If they are
| evenly spaced, there is no difference.
| mikkergp wrote:
| I assume this must mean that the elevators are not equidistant
| from eachother. As in 1 is 10 feet from 2 is 20 feet from
| three.
| PebblesRox wrote:
| They're not necessarily evenly spaced. The middle elevator
| might be a lot closer to one side than the other.
| Jtsummers wrote:
| From the problem statement (first two sentences of the post):
|
| > Imagine a bank of three elevators along a wall. The elevators
| are in a straight line but they are not evenly spaced.
| throw__away7391 wrote:
| Well ok, but if you listen carefully you can hear which elevator
| is coming/closest and always be standing directly in front of the
| one that is arriving.
| [deleted]
___________________________________________________________________
(page generated 2022-07-06 23:00 UTC)