Stephen Downes’ new column on e-Learn does a great job of showing that solving the informational cascade problem is more challenging than I had presented it to be in my own article on the topic. In fact, his own analysis reveals that the problem may be harder to solve than even he himself suggests. The problem, as is often the case, is largely due to those pesky externalities, i.e., reality stubbornly refuses to conform to an elegant theory (and alas, Stephen is even more of a sucker for an elegant theory than I am). (more…)
Tag: Stephen-Downes
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Learning Objects Aren't Legos, Part II
In my last post, I agreed with Stephen Downes that we have to be careful not to take our analogies too literally and specifically pointed out flaws in the “learning-object-as-software-object” analogy. Sometimes the best way to make sure an analogy doesn’t get too deeply rooted is to counter it with another analogy that causes just enough cognitive dissonance to keep you from getting intellectually lazy. (The classic example of this is the light-as-a-particle/light-as-a-wave analogy pair.) I’m going to attempt to create that kind of duality by balancing my course-as-a-sentence-of-natural-language analogy with another one. (more…)
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Learning Objects Aren't Legos, Part I
I’ve been looking forward to having the time and energy to respond to Stephen’s most recent response to the whole pattern language of educational experiences conversation.
Stephen writes:
Even so, [Michael] effectively finds the source of the tension: “I believe that the rules for re-using experience patterns and the rules for re-using content are respectively analogous to the rules of syntax and semantics.” I would say they are analagous in use, but they are not isomorphic – there is nothing, say, in the placement of an image on a web page, or the playing of an audio clip with some video, that corresponds to the rules outlines in Chomsky.
My initial reaction was that Stephen’s point is so obviously true that it’s almost not worth saying. But that initial reaction was wrong. Because the mistake that Stephen is warning about with respect to the language analogy is exactly the mistake that the majority of accounts of learning objects (especially the earlier accounts) have made with respect to the analogy with object-oriented software. (more…)
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Re-usable Learning Content Objects or Re-usable Learning Experience Objects?
Yesterday, Stephen Downes replied to my most recent post on educational pattern languages:
Michael Feldstein is on the right track, mostly, with his exploration of the applicability of pettern language to learning. In this brief item, he asks, “Can we deduce sort of generative grammar of educational experience that enables us to string together these building blocks into ‘sentences’ of educational experience that are complete in both the functional and the humanistic sense?” And I respond – where was it written that language must be composed of building blocks strung together?
The glib answer would be “Aspects of a Theory of Syntax, Noam Chomsky, 1967.” (I happen to live with a linguist, in addition to having taken more than a few linguistics courses myself.) But as I say, that would be the glib answer, because I’ve read enough of Stephen’s work to know that his position on learning objects is considerably more sophisticated than saying “Sorry, no such thing.” To be honest, I’m not 100% sure what Stephen’s objection is here, but I do have a suspicion, and it has to do with some ideas he laid out in his paper “Design Standards and Re-usability”.
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The Definitive Article on Educational Blogging
I’m going to do something I normally don’t like to do an echo blog this. Stephen Downes’ piece on educational blogging in EDUCAUSE is currently the definitive piece on blogging in education. Well worth the read whether you are a newbie or a veteran. I don’t really have anything of use to add here; Stephen pretty much covers it all.
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Informational Cascades, Network Theory, and Behavioral Economics
Stephen Downes’ mention of my article on informational cascades (thanks for the plug, Stephen) led me to his post in the trdev discussion group. He writes:
In network theory, ‘groupthink’ is an instance of what is known as a cascade phenomenon. A cascade occurs (all other things being equal) when the propogation of a property (an idea, a software acquisition, a disease) exceeds 1 – that is, each instance of the phenomenon replicates on average at least one time. It is important to note that the political organization of the group is irrelevant – that’s why mixing ideology with the study of groups can be dangerous.
Classic examples of this principle include stock market bubbles, ranging from the tulip mania that swept through Holland in the 1630s to the Tech Bubble we just experienced to the widespread adoption of email to the influenza epidemic of 1919.
While Stephen is correct to point out the interest that network researchers have in cascades, and while some network researchers are interested in informational cascades in particular (for example, Duncan Watts has a small section on them in Six Degrees), it may be worthwhile to point out that informational cascades come from a different intellectual lineage.
For many decades now, economics has been dominated by the “rational choice” model of human behavior. This basically says that, when making a decision, humans look at how likely it is that that a given option will produce the desired outcome and the expected utility of that outcome. People (according to the model) choose the option that is most likely to produce the best outcome.
Except there are lots of cases where people clearly don’t perform these calculations as the rules of logic and statistics would require. They are doing some kind of calculations, but not exactly the ones that we would expect from the rational choice model. So a school of thought has developed within economics and psychonology that suggests that humans use mental shortcuts to make approximations of those utility calculations. Often those shortcuts will lead to a “good enough” answer with much less time and mental effort, but occasionally they lead people astray. This model, called the “bounded rationality” model, is the heritage from which informational cascade theory comes. Listening to the advice of trusted friends and colleagues is one of those short cuts, and it is the essential mechanism that leads to informational cascades. (A whole list of these shortcuts is being researched in the field of psychology called “heuristics and biases.” There’s also a rich literature on it within behavioral economics.)
At any rate, what’s interesting is that informational cascades happen to map so well to network theory despite the fact that they come from a totally different research thread. In my view, one of the more fertile and interesting ways to start figuring out what kinds of wild and whacky things can happen in online knowledge sharing is to overlay heuristics and biases theory on top of network theory.
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Help Break the Power Law: Downes Leads the Way
In the August 1st edition of OLDaily, Stephen Downes does the e-learning community a great service. (I would have provided a hyperlink to the edition, but the site doesn’t seem to have conventional permalinks and the page hasn’t been rolled over to the persistent site archives yet. Poke around at http://www.downes.ca and you’ll find it pretty easily.) He provides a list of e-learning weblogs that do not yet have inbound links, which gives them very low ratings on Technorati (and probably also means that they don’t show up well on Google searches). These sites tend to get ignored because…well…they have been ignored already, and people tend to gravitate toward sites that have traffic. (As Downes points out, this is known as the Power Law. In addition to the Clay Shirky blog post that he references, Duncan Watts’ book Six Degrees has some good stuff on power laws in it.)
I, for one, intend to scan the list of blogs, subscribe to the RSS feeds of any that look promising, and look for opportunities to link to the worthwhile posts. I encourage all readers with their own weblogs to do the same.