A physicist loose among the liberal arts

Some Networks are Simple

In which the Idiosopher gets to do Inklings stuff on the clock.

logo of the winter simulation conferenceLast summer, the blog started following Sørina Higgins’s suggestion about network analysis to see how interactions between the Inklings in real life turned into stylistic evolution in their literary styles. I haven’t mentioned it since, due to a lack of discoveries that are interesting (even to me).

This week was the 2017 Winter Simulation Conference, a world-wide hootenanny of computer-simulation experts. With all my responsibilities discharged, I got to spend the last half-day attending talks on anything that sounded interesting.  Here’s a good one from Wai Kin (Victor) Chan of Tsinghua University:

This paper studies social influence (i.e., adoption of belief) using agent-based simulation and regression models. Each agent is modeled by a linear regression model. Agents interact with neighbors by exchanging social beliefs. It is observed that if individual belief is linear in neighbors’ beliefs, system-level belief and aggregated neighbors’ beliefs can also be described by a linear regression model. Analysis is conducted on a simplified 2-node network to provide insight into the interactions and results of general models. Least squares estimates are developed. Explicit expressions are obtained to explain relationship between initial belief and current belief.

Social networks are complicated. People go in and out, they talk more or less, they form cliques, etc. If you want to measure things about them, you usually have to build a computer model with a clock and a bunch of “agents” in it. An agent is (in this case) a person with ideas (represented by a number), and as time advances, the agents pick up ideas from each other. Then you inspect the agents after a the simulation has been calculated and find out what ideas each agent has absorbed.

What Prof. Chan has discovered is that, as long as each person in a social network only picks up an idea from three others (which is comparable to the situation for the Inklings), all the complicated stuff drops out – the results of the full-powered simulation always look like a straight-line influence!  This paper is his attempt to prove that’s actually true.  If he’s right, then the spread of some ideas through a literary group will show a very simple pattern, and a literary scholar will be able to do lots of Digital Humanities research with just a spreadsheet. (Hi, Sparrow!)

An anecdote: another thing I did last summer was serve on a jury.  We had to decide on a prison sentence.  At the beginning, we went around the table and got everybody’s first impression. There was quite a bit of difference among us.  After four hours of discussion, which got pretty acrimonious at times, we agreed on a number that was within 5% of the average of everybody’s initial opinion.  That’s what a social-influence model would predict, if Prof. Chan is correct.

If the idea you’re studying can be cast as how strongly an opinion is held, on a scale from 0 to 1, then a linear regression is all you need to solve it.  That’s what I suggested Theosophy might look like, in the post from last July.  Division of territory, such as giving up Arthurian legends to one colleague, space travel to another, and focusing your own attention on time-travel, isn’t describable this way.

Prof. Chan started off his talk by saying the topic was just his own interest, not funded by any organization, and it wasn’t finished yet and he didn’t know what it meant, and the talk was still interesting.  My new scholarship goal is to be able to do that.

Irrelevant note: today is Idiosophy’s second bloggiversary.



The Opposite of Amenity


Origami with Quotes


  1. Hugo Dyson, by his railing against Tolkien’s elves (i.e., ‘not another f***ing elf’), seems to have over time ‘clapped a stopper’ (as Jack Aubrey might have said) over Tolkien’s public readings, at least in the larger group. How do you measure this?

    Lewis claimed that Tolkien was as hard to influence as a bandersnatch, but a) this is just Lewis being clever, and b) Lewis was clearly able to influence bandersnatches. Which is not to say it was easy.

    The number of Inklings present at any given time varied greatly, and Barfield was there far less than others.

    This will all come down to an uncertainty principle in the end.

    Winter Simulations? If Winter were coming, it might look like this?

    • Joe

      Reconstructing the face-to-face meetings among the Inklings would be a formidable task. I’ve been thinking in terms of their published texts instead, because those are fixed. Besides, the published texts are the only reason we care about them.
      But now you’ve got me imagining the future: if some brilliant author comes out of Signum/Mythgard, future literati will have all the webinars and forum discussions in digital format. The sort of study you’re describing will be fairly straightforward. I’ve already heard Corey using in Mythgard Academy sessions things he heard at Moots. An AI will be able to do the complete job, and track the influences directly.

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