Tracing the 2008-2009 Financial Meltdown Through a Metastable Phase Space We can trace a path through the phase space shown in Figure 1 that shows the same kind of behavior as the financial world went through during the 2008-2009 meltdown. Figure 1 shows a “path” going from a low-active state to a high-active state (3) back to low-active state (7) again. (To be continued)
Modeling the 2008-2009 Financial Meltdown Using Metastable State Phase Transitions Now that we’ve weathered the crisis of 2008-2009, we can prudently ask ourselves: “What are the warning signs of imminent meltdown? How can we predict – and act prior to – a major market collapse?” This post continues the theme begun in the previous post, of playing with a not-quite Gedanken experiment; looking for a useful model that explains what happened with the U.S. financial system at the end of…
A disclaimer. Before you (or I) go any further with this, an upfront and blanket disclaimer. This is not a real, true, serious modeling effort. It is not even a true gedanken-experiment (German for “mental experiment,” or mental walk-through.) If anything, this is a little warm-up exercise. An attempt to stretch and flex some “modeling muscles” that have not been used for a couple of years. (And in good cause, I might add – I’ve just completed a book, see…
Modeling Nonlinear Phenomena – What is “X”? Many of us grew up hating word problems in algebra. (Some of us found them interesting, sometimes easy, and sometimes fun. We were the minority.) For most of us, even if we understood the mathematical formulas, there was a big “gap” in our understanding and intuition when it came to applying the formulas to some real-world situation. In the problem, we’d be given a set of statements, and then told to find “something.”…
The Origin of Wealth – and Phase Transitions in Complex, Nonlinear Systems Once again, after a nearly two-year hiatus (off by only a week from my first posting on this in May of 2010), I’m getting back to one of my great passions in life – emergent behavior in complex, adaptive systems. And I’m once again starting a discussion/blog-theme referencing Eric Beinhocker’s work, The Origin of Wealth. Since this book was originally published (in 2006), we’ve seen an ongoing series…
Writing to you within hours of summer solstice, 2010 – we now have 2 1/2 years (approximately) to the time that has been targeted by multiple cultures as a “pivot point” in human experience. The idea that we are accelerating in our experience on this planet is not new. Right now, this idea is receiving a great deal of attention – too much of which is “acceleration” of emotional content, and not an objective assessment. In this sense, John Smart’s…
Complexity and Graph Theory: A Brief Note Santo Fortunato has published an interesting and densly rich article, Community Detection in Graphs, in Complexity (Inter-Wiley). This article is over 100 pages long, it is relatively complete, with numerous references and excellent figures. It is a bit surprising, however, that this extensive discussion misses one of the things that would seem to be most important in discussing graphs, and particularly, clusters within graphs: the stability of these clusters. That is; the theoretical basis for cluster…
Phase Spaces: Mapping Complex Systems I’ve spent the day on cloud computing. Yes, there will be a course on it at GMU this Fall of 2010. And cloud computing is simply a technology; a means of getting stuff done. In and of itself, I think there are more exciting things in the world — such as phase spaces. One of the classic nonlinear systems is the Ising spin glass model. This system is composed of only two kind of particles;…
In Section 2.3, we get to the meat of Sennelart & Blondel’s work, which is a graph-based method for determining similar words, using a dictionary as source. Their method uses a vXv matrix, where each v is a word in the dictionary. They compare their method and results with that of Kleinberg, who proposes a method for determining good Web hubs and authorities, and with the ArcRank and WordNet methods. They test the four methods on four words: disappear, parallelogram,…
(Direct continuation of yesterday’s post, w/r/t Senellart & Blondel on “Automatic Discovery of Similar Words” in Survey of Text Mining II. I give the references that cite, which I discuss in this post, at the end of the post.) In Chapter 2’s revieww of previous methods and associated literature, Senellart & Blondel start with banal and get progressively more interesting. The one thing I found interesting in the first model that Senellart and Blondel discussed was that the model was…