Tag Archive: next door neighbor


(Submitted by Skepticality listener Michael O’Dea

Hi there,

I enjoy the show and want to tell you my against-the-odds-story.

I am from Dublin, Ireland and I was on vacation in Boston, visiting my cousin about 20 years ago.

There was a free public concert in the Boston Common park. (It was Kid Creole and the Coconuts, not that that is relevant!)

I was with an American friend who was a server in a Boston restaurant (Legal’s) at the time. As we enjoyed the music he met a colleague from the restaurant who was with a companion and they chatted for a few minutes as we watched the gig. My friend then went to introduce me, when the companion turned around it was my next-door-neighbour from Dublin!

We had not seen each other for years and had no other connection of any kind other than growing up in adjacent houses.

What do you think?


Below are the extended notes provided by cognitive psychologist and statistician Barbara Drescher for use in Skepticality Episode 239.  Take a look and leave your comments below. Also, please be sure to listen to the podcast for our own hilarious commentary. Also, visit Barbara’s blog.

I think this is an interesting coincidence! Normally, I would talk about the factors that would increase the probability of this happening, so I will, but there are really very few. People living next door to one another are much, much more alike than two people chosen at random from the global population. They are more likely to be close together in S.E.S. (socioeconomic status), for example. They are more likely to be exposed to similar cultural icons (such as music genres). Factors such as these may exponentially increase the probability of running into each other at just such an event.

However, given the astronomically small base probability (e.g., given all of the people in the world, the probability of any two people, chosen at random, would meet), this is still a story with crazy odds.

Consider the factors that don’t really come into play here, but have in similar stories we have encountered. For example it is unlikely both been inspired to visit by the same event (e.g., hearing a mutual friend talk about visiting Boston). They may have been inspired to visit (assuming the companion was also visiting and not living there) by cheap airfare to the U.S., but then why choose Boston? The probability that they all met each other through mutual friends is greatly reduced by the fact that the Americans know each other because they work together (unless, of course, they knew each other before working there).

So we must rely on the mathematical rule that we should expect at least some low- and even astronomical-probability events to occur in our lives, given the large number of events that occur.

(Submitted by Skepticality listener Garrett)

So, recently I was at the gym that I have been going to for the last ten years. This gym is convenient for me because it is about five minutes from where I regularly teach, however it is about 30 miles from my house driving east.

I befriended an acquaintance at the gym, maybe three or four years ago, and we have been getting to know one another little by little. Over the years I have learned many things about Chris – surprisingly that we have the same employer (but never ran into one another because we are in buildings on the opposite side of town – not that weird – a lot of people work there) among other things. I also learned that he lives about 30 miles north of me, but that we share the same supermarket halfway and just never saw one another there either, which would mean that he lives about 30 miles from work as well, albeit on the hypotenuse angle. Little things like that.

Two weeks ago, I was talking with him, and he was describing having a friend in the town I live in. As a matter of fact, he was the godfather of their child who is about three years old – a result of his being in a long term relationship with the uncle of the child, and becoming a very good family friend. Before I told him where I lived specifically, he describes how he gets to their house for perspective – it is the same exit, the same turns, and the same street as me.  As a matter of fact, it is my next door neighbor.

But that isn’t the strange coincidence.

The strange coincidence is that we are very good friends with these neighbors, and my son loves playing with their three children. My wife lets me sit out the children’s parties out of compassion for my sanity…  But it turns out that at all of the family gatherings, she has befriended the exact same acquaintance and has known him for years just as I have. Furthermore, we have told one another anecdotes about him, without ever mentioning him by name even though he has a very common one, and told one another that we should meet him and would get a real kick out of him!  We have had the same acquaintance for years, from completely different circumstances, and didn’t even know it!

Imagine his what his surprise would have been running into our family at the supermarket on a grocery run?

What are the odds of a married couple having a long term acquaintance in two different contexts, especially when a 90 mile perimeter triangle of geography is involved??


Below are the extended notes provided by cognitive psychologist and statistician Barbara Drescher for use in Skepticality Episode 229.  Take a look and leave your comments below. Also, please be sure to listen to the podcast for our own sarcastic and hilarious commentary. Also, visit Barbara’s blog.

It’s impossible to calculate the odds of this, given the number of variables involved. This is really fun story, and it is a shame that I have to ruin these great stories by focusing on what makes them less interesting, but that’s my job, so here goes:  There is one very important fact that makes this story much less “impressive” probablistically-speaking, and that’s the fact that similarity is attractive. We tend to like people we share interests, qualities, values, and identities with, and when we discover commonalities, the bonds grow stronger.

So, a married couple befriending (and liking) the same person is highly likely. That leaves only the coincidence that they both met this man years ago in situations which are likely to repeat opportunities for bonding. The conjunction of those events is clearly attached to a low probability, but not astronomical.