Edgeworth Connections
It’s a small world.
This year I am supervising an undergraduate project student who is looking at approximations to probability distribution functions. This project was inspired by a nice paper on the arXiv by Elena Sellentin, Andrew Jaffe and Alan Heavens about the use of the Edgeworth series which I blogged about here.
It turns out that the student who picked this project hails from a place very close to Edgeworthstown in County Longford. I’ve been through there on the train going to and from Sligo, but I never thought much about the possible connection, assuming the name was a coincidence. When I met my project student yesterday for our weekly discussion, however, he told me he had looked into it and the results are very interesting.

The Edgeworth series was invented by Francis Ysidro Edgeworth (1845-1926) who was a political economist and philosopher was born in Edgeworthstown. He was the grandson of the Richard Lovell Edgeworth (1744-1817) who had no fewer than 22 children (including the novelist Maria Edgeworth) and was a founder member of the Royal Irish Academy. In a manner not untypical of the Anglo-Irish landed gentry, the Edgeworths renamed the local town from Meathas Troim (anglicized form Mostrim), c.f. Parsonstown.
There is a directly astronomical connection with the Edgeworth family too. Kenneth Edgeworth (1880-1972) was another member of the Edgeworth dynasty, `one of ‘the archetypal gentleman literary and scientific families’ who had sufficient private income to be able to pursue a diverse range of interests. Kenneth Edgeworth was an independent theoretical astronomer, best known for proposing the existence of a disc of bodies beyond the orbit of Neptune in the 1930s. Observations later confirmed the existence of this structure, often called the Kuiper belt or, especially in Irish circles, the Edgeworth-Kuiper belt.
Here’s the front page of one of his astronomical publications:
Anyway, what’s the probability that a student would randomly pick a project involving a method invented a person born just a few miles away from his family home?

October 25, 2024 at 12:36 pm
Not just an astronomer but a time traveller.
October 25, 2024 at 12:39 pm
Extending Lognormal using Edgeworth of log x instead of x has also been tried..
November 3, 2024 at 8:42 pm
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