tag:blogger.com,1999:blog-9192597712746432631.post8497002869926275239..comments2024-03-09T09:06:35.288+00:00Comments on Notes from Two Scientific Psychologists: Chemero (2009), Chapter 5: Guides to DiscoveryAndrewhttp://www.blogger.com/profile/16732977871048876430noreply@blogger.comBlogger15125tag:blogger.com,1999:blog-9192597712746432631.post-20590397890615891852011-12-22T23:21:05.602+00:002011-12-22T23:21:05.602+00:00The noise term in the HKB is simply parameterised ...The noise term in the HKB is simply parameterised white noise; perfectly sensible, but nothing specific to coordination. Yes, it was predicted to increase prior to a phase transition, but that's a standard feature of this type of dynamical system.<br /><br />Contrast this to the noise in <a href="http://psychsciencenotes.blogspot.com/2010/11/perceptionaction-model-of-coordination.html" rel="nofollow">Bingham's model</a>; proportional to relative speed to create the differences at 0 and 180 (<a href="http://psychsciencenotes.blogspot.com/2011/09/coordination-dynamics-and-relative.html" rel="nofollow">recently backed up by data</a>). Very particular to coordination, and grounded explicitly in perceivable information.Andrewhttps://www.blogger.com/profile/16732977871048876430noreply@blogger.comtag:blogger.com,1999:blog-9192597712746432631.post-52501773765593895282011-12-22T05:14:47.546+00:002011-12-22T05:14:47.546+00:00Fred,
I'm not as familiar with these models as...Fred,<br />I'm not as familiar with these models as I should be. From your comment I gather that the "noise" term in the HKB model is not equivalent to the "error" term slapped on the end of most any statistical model? The error term in the statistical models simply states "and sometimes our model is wrong", that is, it does nothing but help the modeler save face in light of an incomplete or incorrect model. In contrast, you seem to suggest that the "noise" variable in the HKB model indicates adaptive variation that aids the organism, with the model merely reflecting that.<br /><br />Am I getting this right? If so, could you elaborate a bit?Eric Charleshttps://www.blogger.com/profile/17412168482569793996noreply@blogger.comtag:blogger.com,1999:blog-9192597712746432631.post-68710217112461327142011-12-22T05:13:01.778+00:002011-12-22T05:13:01.778+00:00This comment has been removed by the author.Eric Charleshttps://www.blogger.com/profile/17412168482569793996noreply@blogger.comtag:blogger.com,1999:blog-9192597712746432631.post-28951962119127099282011-12-21T19:14:53.287+00:002011-12-21T19:14:53.287+00:00> Case 1: Modifying the HKB model with a noise ...> <i>Case 1: Modifying the HKB model with a noise term to fit the data<br />Schöner, Haken & Kelso (1986) added a noise term to the HKB data. It's not at all clear how this is supposed to count in favour of the HKB as a guide to discovery, given that noise terms are standard in models. All that happens is the model fits the data better;</i><br /><br />Objection, m'lud. The noise does a hell of a lot more than improve data fitting. It is absolutely necessary to ensure symmetry breaking, to ensure that the system never gets stuck in an unstable equilibrium, and its effect is predicted (predicted, not observed) to get larger as an attractor becomes shallower (critical fluctuations). Noise within coordination dynamics is terrifically important.Fredhttps://www.blogger.com/profile/12698509790614656032noreply@blogger.comtag:blogger.com,1999:blog-9192597712746432631.post-45360093546347769282011-03-19T08:28:20.350+00:002011-03-19T08:28:20.350+00:00Eric, I agree with you to a point. I've blocke...Eric, I agree with you to a point. I've blocked pointless and badly run affordance studies at review only to see them show up unchanged in the Ecological Psychology journal, and I find that a worry. <br /><br />The dynamic touch literature is another example of getting stuck chasing their tail. I'm still waiting for someone to take the next step, namely try to identify the (kinematic) information specifying the (dynamic) inertia tensor. People clearly perceive it - but how?<br /><br />I do agree with Tony's take on the dynamic touch literature, that it's an important part of the story because it's rigourous and not about vision. Those are no small things.Andrewhttps://www.blogger.com/profile/16732977871048876430noreply@blogger.comtag:blogger.com,1999:blog-9192597712746432631.post-49654974162668319812011-03-19T00:46:05.526+00:002011-03-19T00:46:05.526+00:00Andrew,
I don't know the dynamic systems worl...Andrew, <br />I don't know the dynamic systems world as well as the eco-psych world, but it seems to me that everything in the eco-psych world is continued past the point of usefulness. <br /><br />For example, the stuff on detecting the length of wielded rods was great, but it is time to put it in a text book, leave it as foundation, and get on with life. If I see one more talk showing that you can detect the length of a rod by wielding it in a slightly different way, I am likely to scream (probably I'll have the good sense to walk outside first). You can detect it free wielding the rod, if the rod can only rotate in a plane, if the rod is attached to a glove, taped to your back, if it is under water, if it is in oil, if you are holding it generally upright or generally horizontal, etc., etc. <br /><br />Don't get me wrong, the initial work on this was foundational, and great. It's just that its long past the time (in my opinion) that anything new is learned by continuing with it. <br /><br />Eric<br /><br />P.S. Contorting data to fit a model is a different sin.Eric Charleshttp://charlespsychology.comnoreply@blogger.comtag:blogger.com,1999:blog-9192597712746432631.post-716448795952732782011-03-18T14:48:36.729+00:002011-03-18T14:48:36.729+00:00Fair comment. I'm inclined to think the model ...Fair comment. I'm inclined to think the model waaaay overstayed it's welcome, and it really got into people's heads as somehow something real (see: <a href="http://psychsciencenotes.blogspot.com/2010/09/learning-novel-coordination-things-get.html" rel="nofollow">all the attractor dynamic stuff</a> on learning that ended up making incorrect predictions). Watching people try to contort the data into the HKB approach has been a worry. <br /><br />But I must remember not to down play the fact that the foot in the door was real, and counts as real progress.Andrewhttps://www.blogger.com/profile/16732977871048876430noreply@blogger.comtag:blogger.com,1999:blog-9192597712746432631.post-25044320647167593972011-03-18T13:55:39.884+00:002011-03-18T13:55:39.884+00:00One thing to keep in mind here is that the guide t...One thing to keep in mind here is that the guide to discovery problem would seem to indicate that it is impossible to have a progressive scientific research program based on modeling phenomena. The decade+ run of HKB, and the fact that, as Andrew put it, got “a foot in the door for dynamics” shows that a family of mathematical models can be a guide to discovery. That, really, is the whole point of the chapter.<br /><br />Andrew is surely right that HKB has run its course. Even Kelso admits that. At the (profound) risk of downplaying the personal hardships that he endured, we might compare HKB to Jackie Robinson. Jackie Robinson was a great baseball player, but he wasn’t the best even during his own era. He wasn’t perfect, for example he was a prominent supporter of Richard Nixon. But he is really important and rightfully deified because he “got a foot in the door” for African-American baseball players, something which played an important role in the Civil Rights movement in the US.<br /><br />Don’t get me wrong: HKB is no Jackie Robinson, not even close. But the strained comparison might make sense of the way many people (including me) hold HKB in such high regard. HKB was the first of its kind, and it showed you could do scientific psychology by applying nonlinear dynamical models to human action. Lots of good stuff wouldn’t have happened without it, including what Andrew is calling the Bingham model, which of course, Andrew had no small hand in. <br /><br />OK, I look forward to further bashing in Chapter 6!Tony Chemerohttp://edisk.fandm.edu/tony.chemeronoreply@blogger.comtag:blogger.com,1999:blog-9192597712746432631.post-21636154391075304152011-03-18T09:31:13.471+00:002011-03-18T09:31:13.471+00:00To Eric's students - if you're a little we...To Eric's students - if you're a little weirded out by the maths in the HKB model, you may want to play with <a href="http://dl.dropbox.com/u/5574713/HKB%20Model.xls" rel="nofollow">this Excel file</a> I made to plot the model out. If you change the A and B parameters, you change the frequency of the movement being modelled.<br /><br />I should expand this to include the learning prediction sometime.Andrewhttps://www.blogger.com/profile/16732977871048876430noreply@blogger.comtag:blogger.com,1999:blog-9192597712746432631.post-20117002856850150192011-03-18T09:24:45.054+00:002011-03-18T09:24:45.054+00:00Eric, I think my main problem is while that the HK...Eric, I think my main problem is while that the HKB was indeed a short term shot in the arm for the field, that's all it was. It did get people asking questions they hadn't done previously, and measuring things they hadn't thought to look for previously; but it really quickly stopped being able to account for the data it was producing.<br /><br />At that point, the sensible thing to do would have been to jettison the HKB model itself but keep the basic idea (modelling perception action as a non linear dynamical system). This was the thing it had actually contributed: a foot in the door to dynamics. But instead, everyone deified the model itself, which has led to the field chasing it's tail for a long time. Only Bingham has learned the lesson and moved on, and it's been an uphill battle.<br /><br />So right; my concern with using models like this as guides to discovery is to give too much weight to the model.Andrewhttps://www.blogger.com/profile/16732977871048876430noreply@blogger.comtag:blogger.com,1999:blog-9192597712746432631.post-71895258367052813592011-03-18T02:47:32.105+00:002011-03-18T02:47:32.105+00:00I am an undrergraduate and as I work through this ...I am an undrergraduate and as I work through this book, most of what I read has sort of been over my head and I was really scared when the equations came up in this chapeter. As we go on though, I'm beginning to understand much more than I initially did. Especially helpful in this chapter was definately the cases and examples in them. For example, in the 8th case the gear problem help me better understand what was trying to be said.Rashonda Chttp://www.facebook.com/home.phpnoreply@blogger.comtag:blogger.com,1999:blog-9192597712746432631.post-22562798696327795862011-03-17T03:38:35.669+00:002011-03-17T03:38:35.669+00:00I was also a bit frustrated with this chapter, and...I was also a bit frustrated with this chapter, and not fully convinced by the discussion of the HKB model. However, I do not think the situation is a bad as Andrew describes. The two inclinations which are put at odds are this: 1) We want to favoring approaches that lead to new discovery, by which we usually mean that the approaches make clear predictions, which are then confirmed. (In my favored technical language, "the intended implications of the model are verified.") But... 2) many things lead to new discoveries, often quite exciting ones, which are not really predicted in the classic sense of the term, and we don't want these discoveries to count as much. <br /><br />So, the HKB model was there, and using it, in a Radical Embodied Cognitive Psychology kind of way, new stuff was done. Much of it is somewhat mundane, but still definitely counts as new discoveries (well, we know it works with index fingers, what about middle fingers? what about ring fingers? etc.). Other studies were sort of inspired by the model, e.g. the hypothesis that the model could fit the data, but not with any prediction intrinsic to the model. Often, this required adding new complications to the model, which is awkward, because more parameters fit data better (duh!), and because at some point it is just a different model. <br /><br />All this is a very messy story. I don't think we get to count a more complicated model as a "discovery", so the question is whether attempts to apply the model led to things that do count as "discoveries." Certainly the discovery of similar phase shifting in interpersonal situations count, for example. Thus, I don't think it is terrible that this example was used: it is an example of a type of discovery-inducing activity using the approach championed in the book. However, ultimately, such discoveries due to experiment-inspiration will always be less satisfying than good, old-fashioned prediction from first principles. <br /><br />I'm already rambling too much, time to stop.Eric Charleshttp://charlespsychology.comnoreply@blogger.comtag:blogger.com,1999:blog-9192597712746432631.post-48495916373917522302011-03-15T20:27:23.317+00:002011-03-15T20:27:23.317+00:00Part II:
There are some things I do stand by, thou...Part II:<br /><i>There are some things I do stand by, though. For one, Schmidt et al has been understood by most everyone as genuinely social coupling. There is a cottage industry on social coordination dynamics that has grown out of this work, as you know.</i><br />Well, the original paper talks about social coupling but it's not really. That said, the later stuff Richard and Mike did was genuinely about social phenomena; that would be the literature I'd go to to make this point, not the original paper. But that's just a preference. <br /><br /><i>think they get it right: interpersonal perceptual coupling just is a variety of social coupling. </i><br />Really? I'd be inclined to say it's the other way round, given the biological motion perception literature. I'm surprised you go this way, actually. <br /><br /><i>For another, while I agree that a theory is a better way to have a guide to discovery than a set of flexible models, I think it is a mistake to say, as you seem to be saying, that good science can’t be done without explicit commitment a theory. Look, for example, at the Stephen et al work. As you correctly point out, this work is inspired by the dynamical models of phase transitions. That’s not a psychological theory.</i><br />Well ok, to a point. I think they took a problem and used tools from the dynamics bag to tackle it, and that did indeed take measures you wouldn't normally think to take, etc. That's fair; and to be honest, that's the kind of work the HKB model did early on too. In my more charitable moments I do remember that the HKB did actually kick start a whole field. My problem is still that it was really only a decent first swing at the problem, but it quickly became the entire way in which you talk about coordination. Geoff's approach is much more grounded in the actual mechanisms, and is I think a much more fruitful path. Even for Stephan et al, their work will only really pay off if they keep moving. If they spend all their time tweaking their model, they'll never get anywhere.<br /><br /><i>That said, I do agree that theory is a better guide to discovery than models. It is more flexible, and not only because theories are generally compatible with a wide array of models. This is why the next few chapters are in the book.</i><br />I'm on your side with this bit of the enterprise, although as a heads up, I'm not convinced by the specific 'shoring up' you advocate.Andrewhttps://www.blogger.com/profile/16732977871048876430noreply@blogger.comtag:blogger.com,1999:blog-9192597712746432631.post-50989786323360895232011-03-15T20:26:52.291+00:002011-03-15T20:26:52.291+00:00I admit this chapter got me fairly grumpy. I wrote...I admit this chapter got me fairly grumpy. I wrote most of it a little while back, while I was working through some of the coordination stuff, and my critique of this chapter is grounded in my frustration with our inability to break through the dynamic pattern stuff, no matter how often we break it. Your chapter happens to have a lot of this kind of thinking in one place, so it gave me plenty of focus :)<br /><br /><i>Second, I'm not sure what I'm supposed to have missed about Schoner and Kelso, but I don't dispute your superior knowledge of this literature. </i><br />It's a dense paper, and I stared at it for quite a while. As far as I can tell, the B/A ratio isn't what they tweak to model learning; they simply impose an external dynamic to add a third attractor at, say, 90°. This would be consistent with the Kelso & Zanone literature. This approach is a problem because it's predictions don't pan out (<a href="http://psychsciencenotes.blogspot.com/2010/09/learning-novel-coordination-things-get.html" rel="nofollow">learning is easier near 0°, not 180°</a>), but worse, Zanone now just claims it predicts what happens and never refers to that early stuff. Drives me mad.<br /><br /><i>(I also would have written some of this differently had I read your blog posts on coordination dynamics beforehand.)</i><br />Actually, I've been thinking about this. As I say I'd quite like to turn this into a paper; your paper and this chapter put a lot of things I'd like to address in one convenient place and so it's a useful starting point. But the paper needs to be more than just me being mean about some errors! The plan is to use it as an excuse to lay out a few problems with the HKB approach but then direct attention to Geoff's model and the work that backs it up, to try and take the point but move it forward. It'd be nice to get a dialogue going on this stuff.Andrewhttps://www.blogger.com/profile/16732977871048876430noreply@blogger.comtag:blogger.com,1999:blog-9192597712746432631.post-1311932951311942612011-03-15T20:05:36.271+00:002011-03-15T20:05:36.271+00:00Copying this comment from Tony to here so my reply...Copying <a href="http://psychsciencenotes.blogspot.com/2010/09/learning-novel-coordination-things-get.html?showComment=1300210845342#c9006453754439665261" rel="nofollow">this comment from Tony</a> to here so my reply makes sense :)<br /><br />Tony said:<br />Ouch!<br /><br />Let me begin by copping to some of the mistakes you point to. First, yes, Amazeen, Sternad and Turvey was the wrong paper to cite. Nia Amazeen has already (politely) yelled at me about this. The backstory is that I wrote this chapter while sitting in on Turvey's seminar in 2003, and many of the papers discussed in the chapters are from Turvey's reading list. Somewhere in the 5 years between writing the chapter and the page proofs, the wrong citation from that list got cemented into my text. I plead guilty; I plead guilty also to not having gone back to check which article I read while writing this section. Second, I'm not sure what I'm supposed to have missed about Schoner and Kelso, but I don't dispute your superior knowledge of this literature. Third, my claims about Stephen, Dixon and Isenhower were based on discussions with Damian Stephen, rather than the published paper. In fact, I wrote the section of the book before having seen the paper. It is better to view the work in the 2009 paper, and the work that has followed, as you suggest: as stemming from the same sources as HKB model (i.e., synergetics and the dynamics of phase transitions) than as stemming from the HKB itself.<br /><br />OK, I suck. I wish I could say there weren’t other mistakes in the book, but there are.<br /><br />(I also would have written some of this differently had I read your blog posts on coordination dynamics beforehand.)<br /><br />There are some things I do stand by, though. For one, Schmidt et al has been understood by most everyone as genuinely social coupling. There is a cottage industry on social coordination dynamics that has grown out of this work, as you know. I think they get it right: interpersonal perceptual coupling just is a variety of social coupling. For another, while I agree that a theory is a better way to have a guide to discovery than a set of flexible models, I think it is a mistake to say, as you seem to be saying, that good science can’t be done without explicit commitment a theory. Look, for example, at the Stephen et al work. As you correctly point out, this work is inspired by the dynamical models of phase transitions. That’s not a psychological theory. The experiments are inspired by the models, as attempts to see if there are more phenomena that they apply to. So, as a matter of empirical fact, lots of successful science is inspired by models, without commitment to any particular theory.<br /><br />That said, I do agree that theory is a better guide to discovery than models. It is more flexible, and not only because theories are generally compatible with a wide array of models. This is why the next few chapters are in the book.<br /><br />Thanks, again, for spending so much time on the book.Andrewhttps://www.blogger.com/profile/16732977871048876430noreply@blogger.com