Tuesday, 31 August 2010

Asymmetric walking

When I walk from Mile End Road to Sainsbury's, I almost always walk in through the front entrance. When I leave, I leave by the side entrance. This despite the fact that I walk past the side entrance on the way in.

When I walk into university, I usually do so via Mile End Road and the little bridge you can just about make out on the map. When I walk home from university, I do so via Hamlet's Way and (sometimes) the park.

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As you can see, there is little to choose between these two alternatives in terms of distance (actually, there's probably more to choose between them than I would have guessed - the park seems to win quite clearly) but it seems that there is a pretty regular bias that makes me choose one in one direction and one in the other. There are several other places where I've noticed this phenomenon.

Now, I know that there are lots of situations in which the fastest way from A to B is not the fastest way from B to A, even when walking, but I pretty sure this doesn't explain what's going on here. There's some sort of heuristic governing my decisions, and I can't quite work out what it is. It seems to be something like "if you know you need to turn, do so early". Why am I doing this? Does anyone else do the same thing? Have other, more bizarre heuristics?


Adrianna said...

I have also noticed myself doing this and wondered about it. Currently I live close to Haymarket and I noticed that on the way to prince's street I go down West Maitland street (straight). On the way back I turn on tropichen street and go down Morrison (the small loop not the big one). When I paid attention to the route I noticed I have a bias for getting to the side of the street I want to be on early. On the south side of west maitland, which I walk on coming home, there is a barrier(fence? the word escapes me right now) at the corner and the traffic light is some way up the road. So if you cross and the traffic light and continue straight you end up on Morrison street. A similar thing happened when I lived in Marchmont and went to the Cameo.

My conclusion is that your bias for turning/crossing early coupled with how you react to the environment can explain it. I think there is some thought that goes into where to put crossing points, barriers, wider pavements etc. in order to guide walkers and make traffic run more smoothly.

Brog said...

I've noticed myself doing this around the outside stairs towards the rear entrance of the QMUL maths building. Specifically, when leaving I will find it more efficient to go alongside the stairs and then climb over the railing, but when coming it seems more direct just to walk down the stairs. It's a variant on "turning early" I suspect, or else some strange effect being inside the building has on me.

Lynne said...

Hi, just found your blog.

I would wager that you know your way round the supermarket if you go in by the front entrance. 'Supermarket psychology' is very strong and often subliminal - I wrote an essay about it many many years ago for my General Studies O Level. Easiest essay I ever wrote as I'd read a long article in a Sunday colour supplement just a couple of weeks before, and just hoped the examiner hadn't read the article!

If you enter a supermarket by the front you are following the herd. Straight to the fruit and veg counters, straight ahead to milk and cheese. Whatever. If you have an option to 'escape' by a side exit/entrance then that's fine, you're no longer bound by the subliminal rules as you've finished your shopping. See how your gut feels if you enter by the side entrance.... How many other people do that?

I can't answer for your university entrance/exit choices. Maybe you expect to bump into more friends that way. Or is there a noticeboard that you regularly check? Or do you enter by the same entrance but it's your road route that alters? A particular shop that you pass on the way in? Faster route is irrelevant if you're hungry or want a newspaper etc.