Tag Archive: programming


(Submitted by reader Jim Houston)

A few years after graduating from college in upstate New York, I returned to where I grew up in Pennsylvania and found a job about 20 miles away  from my hometown. The job wasn’t related to my major in Physics, but computer programming was something that was a bit more portable, and within a few months, I was asked to find other programmers for the project team.

Sifting through stacks of résumés is an exercise in looking for familiar experiences that would suggest someone can do the job you need done, so one morning I see a résumé that looks so familiar I could have written it myself. I realized as I read it that I must know this guy and so decided right away to call him in for an interview. He went to the same college as I, graduated the same year, and in the same major.  There were about 100 of us freshmen in the department and we all took the same intro courses for the first two years.  While 100 classmates is not a large group, I  may not have known many of their names, but usually recognized them if we passed each other in the halls.  So that I couldn’t place the  interviewee from the name on the resume didn’t strike me as unusual.

When my classmate walked in for the interview, I felt that I had never ever seen this guy before.  It was so unlikely that we could be in the same classes and not have recognized each other, that we actually spent a fair amount of time in the initial chat comparing notes on where we lived, who our professors were, who we knew etc…  Freshman year, he lived one dorm over in a complex of about 2000 students.  The next year, we both moved up to the newer North Campus dorms and again lived a couple of dorms apart, and for the remaining two years we both lived in apartments that were about three blocks from each other.

It turned out that we probably didn’t take classes together because we were six months out of sync on the prerequisites, but largely knew the same people and had the same professors.

What came next floored me. He not only grew up his entire life in my hometown, but I discovered he lived two streets away from where I had lived my entire life up to that point.  He had gone to a different school system and was on the other side of a major street that I had rarely crossed. He was as convinced as I was that even if we had somehow crossed paths, we had never seen each other before.

So when people bring up stories of chance encounters that demonstrate what a small world it is, I like to bring up my counter story of what a BIG world it is. For twenty years, I lived within two hundred yards of a person with very similar interests, went to many of the same playgrounds, stores, and parks and yet were still complete strangers.

(For the statistically inclined, college size was 16,000 students. Class sizes were about 40 people. The population density of my hometown is 15,000 people per square mile. The number of people who lived on the two streets in question is about 250. The rest is an exercise for the reader 🙂


Below are the extended notes provided by Barbara Drescher for use in Skepticality Episode 201. Take a look and leave your comments below.

I love this story. There is, of course, nothing shocking about the coincidences except that the men did not remember each other at all. This should not be the case given the size of the school and the proximity of their childhood homes. And yet it is not surprising at all to me as a psychologist who has studied attention and memory.

The fact of the matter is that the author almost certainly interacted with the interviewee many times and simply did not notice or remember him. It is even more interesting that neither noticed the other while they were in college. I would expect at least that “I know you, don’t I?” feeling.

We all probably encounter many of the same strangers often, but without an interaction that is out of the ordinary, we don’t even encode their faces. If human beings were not so selective, we would be unable to function as we would need to sort through enormous amounts of information on a constant basis. Instead, we encode what we think might be important later and store it as connections to other bits of information.

To see this for yourself, try to draw the heads side of a penny–right now, without looking at one.  You have seen hundreds in your lifetime and you can probably recreate the gist of the coin and some of the details, but do you know where to put everything? Did you draw something that is actually on the tails side? Is the date in the right place? Which direction is Lincoln looking?

For some fun and interesting demonstrations of selective attention and memory, I highly recommend “The Invisible Gorilla” by Daniel Simons, a psychologist who has studied this phenomena.

(Story submitted by reader David Buck)

I work on contract in the software development field and I specialize in Smalltalk programming – a relatively obscure programming language these days.  I normally have a full time contract but one day, my project leader told me that there would be a gap in the contract and it might be several weeks or months before they could get me back in.

I went into “find work” mode and thought about companies I’d done business with in the past.  I decided that I’d contact one insurance company first. I hadn’t heard from them since Nov 18, 2003 (some five years earlier).  The last I heard, they needed to do an upgrade and I thought that if they hadn’t done it yet, I might be able to help them out.

I frequently do this work under a subcontract for the Smalltalk vendor, so I decided to email my contact there – a fellow named Jim. On the morning of January 28, 2010, I emailed Jim to suggest that we contact the insurance company to see if they needed any work done.  I mentioned that I last heard from them in 2003.  Jim agrees and asks me to send him the email address of the contact person.  I don’t have that email address on my smart phone so I tell Jim that I’ll send it to him after I get home a few hours later.

Well, less than a few hours later (before I got home), I got an email out of the blue from the senior manager of the insurance company.  He wanted to know whether I still did that kind of work and whether I was available to do the upgrade work for them.  At no point did Jim or I communicate with them about this work.  They just sent the request on their own on the very day that we were planning to contact them.  I forwarded it to Jim and we started contract negotiations.

I ended up getting a contract with them for six months and successfully completed the upgrade for them.

So, what are the odds that in the three or four hours between Jim and I agreeing to email them and actually emailing them that they would email me instead after five years of no contact?  Weird.  The Law of Large Numbers works in mysterious ways.


Below are the extended notes provided by Barbara Drescher for use in Skepticality Episode 192. Take a look and leave your comments below.

First, I have to question the reliability of the timing this author outlines, because his (assuming the author is male) numbers don’t add up. The timing is not particularly relevant, but it does demonstrate a possible fallibility of memory or documentation.

Setting that aside, it sounds a lot more unusual than it is. The author not only knew the manager and had worked for him in the past, but knew that he’d done a good enough job that the manager might be interested in working with him again. So, it’s not unusual at all that the manager would call the author when he had work to be done.

This leaves the probability that the manager would need to hire someone on the day the author needed to find work. That is difficult to determine without a good understanding of what was going on in the industry at that time. I think we can all agree that it is an interesting coincidence, but not a shocking one.