Today we went to get our drivers licenses renewed. We saw an old friend there. We haven’t seen her in about eight years (since we moved away from Vermillion, SD).
So what are the chances of running into someone you know in a city the size of Minneapolis? To calculate the odds, you need two pieces of information: the number of people there are to see, and how many of them you see each day. There are three million people living in Minneapolis. How many people do I see each day? If I add up all the strangers I see in the Drivers licence place, and the coffee shop, and the grocery store, restaurant, post office, etc… I suppose I see 100 strangers each day.
Thus the probability that one of those strangers is Muriel is 100 in 3,000,000 or 1 in 30,000.
If you keep looking for her, after a year your odds are up to 365 / 30,000 — or about 1 in 80. Unfortunately, as you start to get to the point that you’ve seen a significant fraction of the people in the city, the chances that you’re seeing the same strangers over and over again increases (the basis for this is the “Bernoulli Distribution”). Nevertheless, I think it is safe to say that you’d be up to around a 1 in 25 chance that you’d have seen her once after four years. So we were pretty lucky to find her after only four years!
Or were we? After talking with her, it turns out that she’s worked only two blocks away from where I work the whole time.
Sigh.
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3 replies on “What are the odds”
how cool to see Muriel again, it is a small world, isn’t it?
well hapilly you have someone new nearby to have lunch dates with………..
A few years back, I ran into someone at the old house I went to college with – she was living only 5 houses down! Jody said something to the effect of, “You can’t swing a dead cat without hitting someone from SD around here.” 🙂 I think your odds are better because many young people come to the cities to find jobs, the culture, etc. Maybe it’s just because the drugs are better. It still is an weird thing no matter how you look at it.