Why does it always happen to me?

Predicting the future is one of the least reliable activities that we humans do over and over again, but it can be regarded as a necessity, because without an expectation of what will happen most of our decisions would be baseless. Of course, there are different levels of predictability: if I let my pen drop, the chances that it will fall in an accelerated movement are fairly high, but it cannot be discarded that my dog can catch the pen on its way down or that a gust of wind can blow it even upwards; on the other hand, the chances that the stock market will rise a 10% in one year are slim, but it has happened in the past, so it cannot be discarded.

Remarkably, even if games including dice have been commonplace since the Royal Game of Ur, approximately 2600 BCE in Mesopotamia, the modern theory of probability had to wait until 1654, when Blaise Pascal and Pierre de Fermat, two French mathematicians, provided a well-reasoned solution for the Problem of Points and so laid the groundwork for the current formulation. Their work has become part of our normal way of thinking these days, from lottery to car insurance, but most of us are still ill-prepared to make probabilistic estimations to the point that many mathematically indisputable results are absolutely counter-intuitive, like the Birthday Paradox or Birthday Problem, which states that in a room with 23 people, the chances that two of them have birthdays on the same date are more than 50%.

Photo: freefoodphotos

This morning Trevor complained, as he was pouring milk on his cereal, that it was always him having to go to the basement for a new carton, because he repeatedly ran out of milk during breakfast. There obviously a significant amount of confirmation bias to this statement, because I do not think he is aware of the times any of us do the same thing, but there is certainly some substance to it: Jason and I just drink a drop of milk in our coffee and Karen not at all, so it is probably accurate to say that he drinks between 80 and 90% of the milk in the house, so by the properties described by Siméon Denis Poisson (yet another Frenchman) Trevor should pour the last drop of 80 to 90% of the milk cartons. Furthermore, both Jason and I have the option of drinking our coffee with slightly less milk if we finish the carton, whereas Trevor definitely needs a certain volume for his breakfast. (This last comment might induce more than one to think that Jason and I are cheeky bastards that finish the milk and do not replace the carton, but it should go almost without saying that we know better than that and we try to bring a new pack upstairs whenever it is necessary.)

This kind of events happen all the time around us, but we tend to disregard the crucial fact of the differences in frequency. If you are the only person eating toast in the house, regardless or how rare the accident is, every time someone in the house drops the toast it will be you, and you will be cursing your "bad luck" doubly, once because you dropped the toast and once because "it always happens to you".

Bad luck exists and the number of near-saves, when I was so close to prevent a negative outcome but ultimately failed, are almost infinite, but next time you shake your fist to the sky in desperation think if, by chance, it only happens to you because you are the only one to whom it can happen. Have a nice evening.