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Where to wait for an elevator (2010)

johndcook.com

31–40 of 115 posts

Re: Where to wait for an elevator (2010)

#32
post #11

Earlier quoted context omitted.

Because you could deselect other peoples choices.

This isn't an argument, as you can also select other people's non-choices.

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...

Re: Where to wait for an elevator (2010)

#33
post #11

Earlier quoted context omitted.

Because you could deselect other peoples choices.

This isn't an argument, as you can also select other people's non-choices.

That doesn't prevent people from getting to their destination.

Re: Where to wait for an elevator (2010)

#34
post #3

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.

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.

2nd floor? You need the exercise.

Re: Where to wait for an elevator (2010)

#35
post #27
post #8

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?

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 changin…

Rather than testing these scenarios, couldn't one simply just(tm) not allow deselection in these scenarios?

Re: Where to wait for an elevator (2010)

#36
post #3

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.

If you want a fun challenge, try making your own elevator algorithm! https://play.elevatorsaga.com/

Re: Where to wait for an elevator (2010)

#37
post #26

Earlier quoted context omitted.

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 auto…

I wonder if there is any improving that system without replacing it.

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.

Re: Where to wait for an elevator (2010)

#38

> 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"?

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.

Re: Where to wait for an elevator (2010)

#39

> 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"?

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.

Re: Where to wait for an elevator (2010)

#40

> 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"?

They’re not necessarily evenly spaced. The middle elevator might be a lot closer to one side than the other.
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