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wwa12y00

If you instead went due north and then due east, that would be two left turns (driveways), one right turn, and three straights. Isn't that a strictly better route?

I assumed turning left into/out of a driveway (i.e. "crossing the street when not on a crossroad") is impossible or at least hard (slow). This is often the case in a dense city. If we're not in a dense city then Taxicab assumption is an error as well.

[anonymous]12y00

Ah, that makes sense. But then doesn't the route direction depend on where the starting and ending points are located, still? With your picture, if the starting point is on the north or east side of the block and the ending point is on the south or west side (as they are), a counterclockwise route works better. If the starting point is on the south or west side and the ending point is on the north or east side, a clockwise route seems to be better. And if there's one of each, you'll end up with a figure-eight route.

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14 What's the name of this cognitive bias?

by pete22

6th Jul 2013

1 min read

14

Picture a circular road on a map. Let's say that my office is at twelve o'clock, my home is at five o'clock, and the post office is at three o'clock.

Now, suppose I have to leave work, pick up a document at home, and take it to the post office to mail it. I know it's faster to walk clockwise home, passing the post office, and then return to it with the letter. But my gut preference is to go counterclockwise, either because of an aversion to retracing my steps, or because that route just ... feels "cleaner" or more efficient somehow, or ... I can't articulate it any better than that.

Does anyone else share this intuition? Is it a manifestation of one or more known/studied effects?

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[-]kpreid12y270

This seems explainable as a simple heuristic — “routes containing retracing-your-steps are likely to be less efficient than other options” — which happens to be wrong in this case.

[-]polutropon12y200

This seems to me to be a permutation of the sunk cost fallacy. If you retrace your steps, you feel as though you're wasting the effort you took to get there in the first place, even though it's already spent and now it makes sense to go back again.

I share the intuition, by the way.

[-]Oscar_Cunningham12y160

I think that this should be in the Open Thread.

[-]kpreid12y110

The slightly longer route also gives you less repetition. If I were in your position, I think I would value it for that — to have more opportunity to make new observations and to practice different actions.

[-]Manfred12y70

Sounds like a sub-type of question substitution, where you're taking the question "what's the best route to take?" and substituting "what route is simplest?" or maybe substituting the unnatural problem of planning a car trip with more common problem of planning the short-term motion of an object like your hand, or a ball.

Alternately, if you feel more driven by the feeling that it's bad to have to retrace your steps, that would be something more like a "purposefulness drive" (I'm calling it this because of an experiment by Ariely), where it's not so much that you are getting the wrong answer first, it's that you're feeling bad about getting the right answer because part of the trip feels "purposeless." It wouldn't actually be purposeless, the feeling would just come from (again) a sort of question substitution where your brain ignores the big picture when deciding how to feel.

[-]MalcolmOcean12y30

I've noticed something similar which seems to be related not to direction or length but to the shape of the path. I realized this weird one when walking to/from class. There was no direct/crowflies/euclidean route from my residence to the classroom building, but several routes of approximately the same length. I almost always took one there and another one home. Part of this is habit, but I think the other reason is some kind of funnel effect: I prefer open pathways, because I feel like they give me more flexibility, or something, and so in each direction I start with the path that feels the most open, even though later it will narrow. Or something?

I confess I don't understand this very well. I think part of it also has to do with how direct the path is at that point. Like I'm more willing to walk perpendicularly (to the absolute path) at the end of my walk than at the beginning. Both directions aside, I can imagine this manifesting in situations where a brief perpendicularity at the start would actually create a much shorter walk, although I'm not quite that irrational in this instance

[-]Alejandro112y40

If I understood you correctly, something similar happens with myself. Schematically, it goes as follows: if I have to go from A to F in the following diagram,

A B C
D E F

and I cannot go directly through the rectangle's diagonal but I can go on the squares' diagonals, I will go A-E-F, and return F-B-A. Is this what happens with you?

The mechanism is probably that the brain at A, knowing it has to get to F, scans all immediately available directions to walk and determines that AE is the one closest to approaching F. That the path that starts going to B will have the same total length is a fact available in Far/analytic mode, but not in the mode that operates if one walks while thinking of something else.

[-]thomblake12y30

Wow, that actually describes a pretty sane heuristic.

[-]MalcolmOcean12y00

Sane unless one of the paths is actually substantially shorter, in which case it's a waste of time that feels efficient.

There are psychological aspects to all of this too. There are several routes from my bus stop to my house right now, and while they all have the same length (Manhattan distance = x+y, i.e. right angles) certain paths feel shorter... I think it's mostly number-of-turns. When I walk straight down the street I live on, it seems really long, but when I walk partway down the adjacent street, then a block sideways, then the rest of the way, it seems somewhat shorter.

[-]thomblake12y00

Well, imagine a planning algorithm that has no memory - then a heuristic like that (maybe with some amount of randomness to avoid cycles and such) might be your best bet.

[-]MalcolmOcean12y20

Yes! That probably explains it better than mine.

[-]CrimsonWool12y30

It's my understanding that people prefer to go counterclockwise in all sorts of situations, it might just be that.

[-]pete2212y20

That's really interesting, but I don't think it's what's going on here. The real-world routes are messier of course, and in the particular one that made me think of this question, my preferred longer route is closer to clockwise. I think it happens both ways.

[-]wwa12y20

Do you live in a country where you drive on the right? If so, you're trained to travel on the right which implies counter-clockwise route. Also, most street lights seem to be set to prefer counter-clockwise movement so you'll hit less red lights if you follow this flow.

[-][anonymous]12y20

How does traveling on the right imply a counter-clockwise route? Given two equal-length ways of getting from one place to another, I'll probably prefer the one that involves fewer left turns, or more right turns. If the road is circular, and both places are outside the road, I'll want to go counterclockwise, but if both places are inside, I'll want to go clockwise.

[-]wwa12y20

I was assuming travelling diagonally in Taxicab geometry and considered 4 potential starting points and 4 potential destinations (on every side of the src/dst block) and also that crossing a two-way street was forbidden or at least difficult when not on a crossroad.

[-][anonymous]12y00

I still don't understand, then. Isn't it easier to travel clockwise around city blocks than counterclockwise? Maybe you could give an example of a trip where going counterclockwise is easier?

[-]wwa12y00

Isn't it easier to travel clockwise around city blocks than counterclockwise?

It is! But that only makes it easier to travel counterclockwise between blocks.

Maybe you could give an example of a trip where going counterclockwise is easier?

Sure, catch: routes Pedestrian would go clockwise in this case and I suppose for a pedestrian the cases are split 50/50. A car is better off counterclockwise in most cases though.

Actually my original model was insufficient - I didn't thought it matters how src/dst blocks are located relatively to each other. I initially missed that pedestrian lights layout is different than that of a car and I didn't list all assumptions, e.g. for a car "go straight" > "turn right" > "turn left" > "turn around" and for pedestrian it depends on which side of the road you are. And all that while we're only in Taxicab!

[-][anonymous]12y00

So assuming you're in a car, your "optimal car" route involves two right turns (into and out of the driveways), three left turns, and three straights. If you instead went due north and then due east, that would be two left turns (driveways), one right turn, and three straights. Isn't that a strictly better route?

(Also, isn't turning right usually easier than going straight? I often make a right turn when going straight would have been prohibited (due to a red light), but I almost never go straight when turning right would have been prohibited (due to a pedestrian or bicycle to my right whose path I would have crossed).)

[-]wwa12y00

If you instead went due north and then due east, that would be two left turns (driveways), one right turn, and three straights. Isn't that a strictly better route?

[-][anonymous]12y00

[-]DavidAgain12y10

I identify with this very strongly. It's even stronger for me if the distance I have to travel is already 'extra': e.g. if I forget my train ticket I'd rather take a much slower bus than spend ten minutes walking back to the house because the latter I feel as intensely frustrating.

Its interesting because you don't just feel it at the point of being about to retrace your steps: you're aware of it as part of journey planning.

[-]Shmi12y00

I have that preference, too. I don't know if it is common enough to have a name.

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