Years ago I traveled to Sweden intending to dig up some Anderson family roots. Although I had little luck tracing back the tree (too many sons of Anders!) it was great fun touring this Scandinavian country that seemed so much like home in Minnesota. One thing they had that we did not was a complete wooden warship—the Vasa —which sank on her maiden voyage due to some engineering issues (since then the Swedes have rebuilt their reputation!). After a dramatic movie-reenactment of this ship’s history, the lights came up and I discovered a dear friend of our family sitting right behind me. Unbeknownst to me they’d also gone for a holiday in Sweden, decided to go to the same museum, etc. Miraculous!
It turns out that from a strictly statistical view, coincidences like this really are not so unexpected. As physicist Freeman Dyson put it, “the paradoxical feature of the laws of probability is that they make unlikely events happen unexpectedly often.” A Cambridge mathematician laid this out in his eponymous Littlewood’s Law of Miracles, which states that in the course of any normal person’s life, miracles happen at a rate of roughly one per month. Dyson provided a simple proof of this law as follows. “During the time that we are awake and actively engaged in living our lives, roughly for eight hours each day, we see and hear things happening at a rate of about one per second. So the total number of events that happen to us is about thirty thousand per day, or about a million per month…The chance of a miracle is about one per million events. Therefore we should expect about one miracle to happen, on the average, every month.”*
I wrote all this about Dyson and Littlewood over ten years ago in my May 2004 DOE FAQ Alert ezine. What reminded me of it was this Science magazine review of a new book titled “The Improbability Principle, Why Coincidences, Miracles and Rare Events Happen Every Day” by Professor David Hand, former Chair in Statistics at Imperial College, London. It lays out these five laws that explain why seemingly rare events are really not that unusual.
None of this surprises me. In regards to the time I ran into a friend from Minnesota in Sweden, such encounters must be common that with so many of our inhabitants being of Scandinavian descent, most all of whom vacation in the summer, and go to the same popular attractions. How many of you have unexpectedly met someone you know while traveling far from home? I’d venture to say it’s the majority. That’s what these statisticians are trying to tell us. They really know how to take the excitement out of life. 😉