[SystemSafety] Mid-19th c railways and "gravity models"

From: Peter Bernard Ladkin < >
Date: Fri, 05 Sep 2014 08:53:10 +0200


I just came across a paper which might interest many here although it is not about safety. It is about planning railway routes back 150 years ago. It is written by Andrew Odlyzko, a mathematician known for his work in cryptology and number theory, who interests himself also for early railway history, which he calls "by many measures the greatest technology mania in history".

Apparently there are things called "gravity models" of social interaction. The simplest says that people interact in proportion to their number, and in inverse proportion to the distance between them, and has been attributed to the US economist Henry Carey in 1958. Odlyzko says that the Belgian civil engineer Henri-Guillaume Desart used one a dozen years earlier, in 1846, to analyse railway routing. But his work was not used.

At that point, the prevailing understanding seemed to be that people would want to travel between centres of population some distance from one another. Gravity models suggest, in contrast, that most journeys are in fact more local. This may not be news to anyone who uses the UK south-east network, nor indeed to anyone who stands on a platform at Bielefeld station between 6 and 8 in the morning.

Odlyzko notes that the cumulative investment in railways amounted to about 60% of UK GDP in 1914, so any better way of routing, resulting in more, and more effective, rail travel, would have affected the overall economy hugely. Not to speak of giving Dr. Beeching much less work to do in 1963. http://www.dtc.umn.edu/~odlyzko/doc/mania09.pdf

The paper is advertised in Risks Forum 28.24, which came out today (actually yesterday evening in the US). Odlyzko has quite a lot on the history of the rail technology bubble at http://www.dtc.umn.edu/~odlyzko/rrsources/index.html

PBL Prof. Peter Bernard Ladkin, Faculty of Technology, University of Bielefeld, 33594 Bielefeld, Germany Tel+msg +49 (0)521 880 7319 www.rvs.uni-bielefeld.de



The System Safety Mailing List
systemsafety_at_xxxxxx Received on Fri Sep 05 2014 - 08:53:23 CEST

This archive was generated by hypermail 2.3.0 : Tue Jun 04 2019 - 21:17:06 CEST