Tuesday, June 21, 2011

What is the propagation speed of a yawn?

On the bus the other day, as I was rolling past waiting commuters on Marquette Ave in downtown Minneapolis, I saw a yawn traveling along through the crowd. Or at least, that was the appearance- it may have just been that people were randomly yawning as I passed. Regardless, that got me thinking: what is the propagation speed of a yawn through a given crowd?

We should be able to express that as an equation, if we choose our parameters wisely. First, let's define "speed", for the purposes of this exercise, as the time required for a yawn to travel a given distance through a crowd in any direction. The reason for that wording will become clear later.

So, that brings us to the equation:
V = d * q * (m / r) * f(C)
d is the average delay between when a person sees a yawn start and starts yawning themselves
m is some distance factor (it can be observed that someone closer is more likely to inspire a yawn than someone farther away- m will have to be determine experimentally)
r is the average distance between crowd members
f(C) is a function of the crowd shape, orientation of individual members to each other and crowd activity

f(C) can be thought of as a "crowd quality" metric, and it will be different for linear crowds (people waiting for the bus, but all facing the sreet), crowds where there is no orienting factor (people waiting for a concert, for instance, who may be facing any direction based on where their friends are), queues, or spectating crowds. It is also likely that by being similarly primed mentally will factor into f(C)- a room full of bored college students is more likely to propagate a yawn quickly than people waiting for a bus, all with different degrees of boredom and internal mental activity.

Now, let's consider directionality. If we pick two arbitrary points and attempt to measure the propagation time between them, we will get a false sense of the travel time because of the meandering of the yawn through the crowd. It is thus better to simply pick a "patient zero" and then watch for a yawn to occur in any person at a given radius away from that person. The resulting scalar value is the speed of a yawn, or perhaps the "speed of lassitude".

Wednesday, June 1, 2011

Why Dunbar's number matters

So, I cast a fairly wide net in terms of things I passively track for potential food-for-thought. Blogs and tweeps, books, articles, etc- I try not to limit myself too much because I can skim pretty quickly across a fairly vast swath of content, even if it IS just a drop in the bucket.

This morning, the following tweet came through, from Tim Hurson:
To ourselves we are a complex of thoughts and feelings. To others we're just a bunch of behaviors.
Really not engineering related, of course, but it meshed well with something else I saw come through my twitter stream- a post about Dunbar's number, which is the supposedly optimal group size of human culture: the number of people that you can conceivably know about and care about. That group of about 150 individuals is your monkeysphere, and people outside of it are, to some extent, not really people in your mind.

I think there's a little more to that tweet than the 140 character limit allows. See, to people who consider you to be inside their monkeysphere, you are a collection of behaviors, and they have collected a series of behaviors to build a heuristic representing you and your expected reaction to future stresses.

To people who do NOT consider you to be inside of their monkeysphere, you are nothing more nor less than what you are doing at the moment. If you cut them off in traffic, you're a jerk. If you hold the door open, you're a nice guy.

The tricky part is, we all have people in our lives (co-workers, fellow bus commuters, hackerspace members) who consider us to be inside their monkeysphere, but we consider to be outside of our own, and vice-versa. This can cause major friction when someone behaves in an unacceptably familiar manner.

I guess my point is, the next time somebody irritates you or angers you, consider the Venn diagram of your respective monkeyspheres. If there is no overlap at all, there's a very good chance that the conflict is highly situational and not due to some intrinsic defect in either of your personalities. If there's a possibility of asymmetrical monkeysphere inclusion, ask yourself if you would change your judgment of their actions if you were closer to them, or if their actions would make sense if they were closer to you (or if they think they are closer to you than you think they are). And if you are within each other's monkeyspheres, then it's probably worth it to deal with the conflict as well as you can before it becomes a major problem.