I send the FT the Polymath crossword solution on a fairly regular basis, but I notice that a greater than expected number of winners hail from overseas. Would I have a better chance of winning were I to send the solution to my friends in Sweden for them to post in an envelope with a foreign stamp?
Tony Waldron, UK
Dear Mr Waldron,
You are not the only one to notice that Johnny Foreigner appears to win with alarming regularity. Still, we must be statistical.
You say that a “greater than expected number of winners hail from overseas”. But you do not say what you expect. The British make up about 1 per cent of the world population. Accordingly, there should be a British victor approximately 1 per cent of the time, or once every two years, on average. I believe the British victory rate is higher than this.
Another basis for forming our expectations is to look at subscribers. Many UK-resident FT subscribers fail to realise that they are outnumbered by overseas subscribers. If the British won Polymath half the time, this would be “more than expected”. The informal estimate of the Polymath team is that the proportion of foreign winners is roughly in line with the proportion of foreign subscribers.
After discussion with the Polymath administrator, I have concluded that her method for picking winners is reasonably random. However, she takes no extravagant precautions to ensure this is so. Perhaps foreign stamps do attract her magpie-gaze.
Even so, you must weigh the fractional additional chance of winning against the time and expense of routing your entry via Sweden. Surely the costs outweigh the benefits, unless you are motivated chiefly by the glory of having your name published in the Financial Times. If so, I believe I have solved your problem.
Also published at ft.com.