tag:blogger.com,1999:blog-269456632024-03-19T12:36:54.960+01:00Brownian thought spaceCognitive science, mostly, but more a sometimes structured random walk about things.mohinishhttp://www.blogger.com/profile/07121978396381676854noreply@blogger.comBlogger186125tag:blogger.com,1999:blog-26945663.post-38146718551374870052012-09-03T16:02:00.000+02:002012-09-03T16:02:13.476+02:00Encyclopedia BrownOne of the reasons I knew early that I was destined for all things Science was my fascination with <a href="http://en.wikipedia.org/wiki/Encyclopedia_Brown" target="_blank">Encyclopedia Brown</a> and the intense frustration when I'd not solve the cases.<br />
<br />
Just read that the author died earlier this year.. <a href="http://www.mediabistro.com/galleycat/54490_b54490" target="_blank">RIP Donald Sobol</a>!<br />
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<a href="http://www.flickr.com/photos/jl-incrowd/2454502401/" title="Encyclopedia Brown Strikes Again (1965) by jl.incrowd, on Flickr"><img src="http://farm3.staticflickr.com/2375/2454502401_5792ecb224.jpg" width="348" height="500" alt="Encyclopedia Brown Strikes Again (1965)"></a>
<br /><div class="blogger-post-footer"><p>_Moss<img src="http://mohinish.s.googlepages.com/mossicon.png" alt="moss" width="16" height="16" /><img src="http://mohinish.s.googlepages.com/feed-icon-16x16.png" alt="feed" width="16" height="16" />Feed_</p></div>mohinishhttp://www.blogger.com/profile/07121978396381676854noreply@blogger.com0tag:blogger.com,1999:blog-26945663.post-51696645799910382052011-10-04T17:16:00.002+02:002011-10-04T17:48:36.550+02:00Downgrade Lion to Snow Leopard on new iMacsGot a new iMac? Came pre-installed with Lion? Want to go back to Snow Leopard for whatever reason? (Unlike the Fanboy, I realize we have different needs). I've been trying to migrate everything off of my work laptop (MacBook Pro) running SL to my new iMac.<div>
</div><div>First I tried just sticking in a SL install disk. It causes a pernel kanic (it just calls it a "panic") and the gray screen if death. Complains of incompatible hardware. Then, I attached my SL Time Machine backup, restarted the Lion-iMac, holding down the ALT key to give me a choice of starting up from different sources (fyi - you CAN see the SL install DVD this way, but when you select it, you get the panic again). Then, I selected the "Recovery HD" option, and tried to install from Time Machine Backup. But again, Lion told me I could not do nada. </div><div>
</div><div>Here's what worked for me. Remember, you take full responsibility for trying these tricks. Keep good backups and backups of your backups in case things get screwy.</div><div>
</div><div>It requires you to have :</div><div>
</div><div>1) Fully upgraded SL to the latest 10.6.8, with all updates in place on your old SL Mac. At some point, in anticipation of Lion, SL had got a Migration Assistant upgrade..</div><div>
</div><div>2) A Time Machine backup from your fully upgraded SL Mac. I have mine on a WD external HD. All the cables to attach the external HD to your old SL Mac.</div><div>
</div><div>3) A firewire 800 cable (the rectangular ones that cost $45[wtf?!]) - of course, make sure both the computers have the firewire ports. Also, if your TM HD also uses firewire, make sure you have multiple firewire ports on your old SL Mac</div><div>
</div><div>Then follow these simple steps:</div><div>(NB: 1&2 are probably not necessary, but better safe than sorry)</div><div>
</div><div>1) Run Disk Utilities on your old SL Mac, repair disk permissions.</div><div>2) Do a Time Machine backup. Turn off Time Machine backups, so it doesn't do freaky stuff during your transfer</div><div>3) Mount the external HD with the TM backup</div><div>4) Restart the old SL Mac, holding down the ALT key. You should see a gray screen with your HD(s) and "Recovery HD". Double click the "Restore HD"</div><div>5) On the Lion-iMac, go to System Preferences, click on Startup Disk, and click Target Disk Mode... to restart the computer in TDM. Attach a firewire cable to the Lion-iMac</div><div>6) When the Lion-iMac restarts, you should see the thunderbolt+firewire symbols floating around the screen.</div><div>7) Attach the other end of the firewire to the old SL Mac. </div><div>8) On the old SL Mac, go to (Disk?) Utilities and click on Restore from Time Machine Backup.</div><div>9) Select the TM backup disk as your source, and the Lion-iMac HD mounted onto your SL Mac as the target.</div><div>10) You'll get a warning that the target will be erased. Sure. Get it running. </div><div>11) At this point, it looked like my old SL-Mac restarted. I unmounted the TM backup disk; couldn't see the unmount button for the (ex)Lion-iMac, so turned it off, got the device removal warning. Unplugged all firewire etc cables. Restarted both computers...</div><div>
</div><div>Everything seems good so far. Mail on the new (now SL) iMac rebuilt databases when it first started, but seems just like the older one. Programs run. No crashes yet.</div><div>
</div><div>hth</div><div>
</div><div>
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</div><div> </div><div class="blogger-post-footer"><p>_Moss<img src="http://mohinish.s.googlepages.com/mossicon.png" alt="moss" width="16" height="16" /><img src="http://mohinish.s.googlepages.com/feed-icon-16x16.png" alt="feed" width="16" height="16" />Feed_</p></div>mohinishhttp://www.blogger.com/profile/07121978396381676854noreply@blogger.com3tag:blogger.com,1999:blog-26945663.post-293184248162484072011-01-26T13:26:00.008+01:002011-04-06T13:50:57.424+02:00Why do some language universals have exceptions?In a recent article, <a href="http://www.mpi.nl/news/news-archive/the-myth-of-language-universals">Evans & Levinson</a> argue that there are no language universals, because for almost any universal, one can find exceptions. Of course, if you're a Chomskyan-like linguist, the obvious simple response is something like this being another case of failing to draw a competence/performance distinction. But still, one needs an explanation of why we find some rare forms; and here is (another) general possibility. <div>
</div><div><i>(Sidenote on Evans & Levinson: Imagine we went around observing living species. We would see a bewildering diversity, and I'm quite confident that for any "rule" relating to the phenotypes, there would always be some exceptions. E.g., swimming mammals, flying snakes, flightless birds, carnivorous plants etc. But from this, should we conclude that there is no underlying "universal" organizing principles? No - we <span class="Apple-style-span" style="font-style: normal;">know</span> that there is an underlying organizing principle, but that the variation can sometimes make it hard to see. But it's a better explanation of the facts than to assume that each species somehow arises independently of the other, in response to the local environmental niche. [Of course, this analogy might not be perfect; living systems do evolve; while it's not clear if languages do/have done in quite the same way.])</i></div><div>
</div><div>The possible explanation for rare forms arises from work on language typology and language change. In the former, one finds broad generalizations, sometimes with exceptions. For example, Jenny C. recently told us all about Greenberg's Universal 18, by which Adjective-Noun and Noun-Numeral combinations are forbidden (so you can't say something like "red balls three"). It turns out that, in a large survey of languages, about 4% actually do show this pattern (on the surface). </div><div>
</div><div>Now we also know that languages change; and in some cases languages change along gradients. Note that this sense of 'gradient' is different from some others, which equate 'gradient' effectively with non-discrete (and hence non-symbolic?) views of language. In the sense used in this post, a gradient is a hierarchy of constituents to which a certain rule can be applied at different levels of the hierarchy. To give an example (thanks to Jenny.C.), consider the hierarchy of DP definitiveness:</div><div><blockquote></blockquote><blockquote></blockquote><blockquote>Pronoun > Definite DP > Indefinite DP/Quantifier > Wh-phrase</blockquote></div><div>where X > Y implies that Y is higher up in the hierarchy than X. So, for example, if a certain grammatical rule (like agreement) applies to Y, it must also apply to X, but not vice-versa. (In the above example, one can think of the left-to-right progression as getting successively more unspecific about the intended referent.)</div><div>
</div><div>Why should a language change from left to right? A general answer (<a href="http://www.bcs.rochester.edu/people/jculbertson/papers/CulbertsonLegendreWECOL2010.pdf">e.g. in this paper</a>) is that it is due to a tendency for generalizations. I.e., if in generation 1 agreement is only on pronouns, and there is even a little evidence for generalizations for definite DPs, over time the regularization bias will quickly move the generalization to the right in the hierarchy. Presumably, there might not even need to be <i>any</i> evidence - if the input is sparse and the learner is trigger-happy, s/he might hypothesize that a generalization holds at a level higher than the one observed in the data.</div><div>
</div><div>But there are two possible scenarios for such gradients like X > Y > Z. One is that this sequence is self-closing, such that X > Y > Z > X ..., much like Rock-Paper-Scissors. In such a scenario, one would expect that, starting from different positions in the hierarchy, and changing at different rates, at any given time one might expect to find all three kinds of systems. </div><div>
</div><div>However, if X > Y > Z, and that's the end of the story, then, over time, the elements higher up in the hierarchy will tend to dominate, and Xs will tend to be infrequent or disappear. </div><div>
</div><div>(A third possibility is that, for different reasons, learners might be able to move to both the right and the left of a hierarchy. In this case too, languages would be expected to be of all three kinds.)</div><div>
</div><div>In essence, the reason why certain grammatical features might be rare is that they represent what a complex system theorist might call repellers - regions that a dynamically evolving system avoids. That is, gradients of change might mostly<i> lead</i> <i>away</i> from some linguistic forms, making them universally rare.</div><div>
</div><div class="blogger-post-footer"><p>_Moss<img src="http://mohinish.s.googlepages.com/mossicon.png" alt="moss" width="16" height="16" /><img src="http://mohinish.s.googlepages.com/feed-icon-16x16.png" alt="feed" width="16" height="16" />Feed_</p></div>mohinishhttp://www.blogger.com/profile/07121978396381676854noreply@blogger.com0tag:blogger.com,1999:blog-26945663.post-70401111943635015782010-11-18T14:38:00.012+01:002010-11-18T18:01:41.392+01:00A rule by another name...<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhUxctdwE_WQiWmkIgJYe60b_qWjaHU50Bscl3JRccfdl3O6IhwJk4jyQ0vmA2EOW2kiOFDR1Dln6381ntA1z4UPnXlTFePYYW0tedFU-ClJiDCxOdFggy_ZTH4keSWt0Xr7RQQ_Q/s1600/s1fig.png"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 266px; height: 245px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhUxctdwE_WQiWmkIgJYe60b_qWjaHU50Bscl3JRccfdl3O6IhwJk4jyQ0vmA2EOW2kiOFDR1Dln6381ntA1z4UPnXlTFePYYW0tedFU-ClJiDCxOdFggy_ZTH4keSWt0Xr7RQQ_Q/s320/s1fig.png" border="0" alt="" id="BLOGGER_PHOTO_ID_5540883744667397474" /></a><div style="text-align: left;">Is this a rule or is this a little portion of an <a href="http://en.wikipedia.org/wiki/Hidden_Markov_model">HMM</a>?</div><div style="text-align: left;">
</div><div style="text-align: left;">Imagine some rule-based system, that has the following:</div><div style="text-align: left;">x -> {x | y}</div><div style="text-align: left;">It's in a made-up notation, but the meaning should be clear enough: 'x' can go to either of 'x' or 'y'. The first part (x->x) is just what this colorful picture represents (minus some probabilities of <i>how likely is it</i> that x->x). In fact, the above figure requires some kind of an identity function (<i>x goes to <b>it</b>self</i>).</div><div style="text-align: left;">
</div><div style="text-align: left;">Here are some more rules:</div><div style="text-align: left;"><ul><li>1. <a href="http://en.wikipedia.org/wiki/Algebra">x=3y</a></li><li>2. <a href="http://en.wikipedia.org/wiki/Natural_number">17</a></li><li>3. <a href="http://en.wikipedia.org/wiki/Bayes'_theorem">p(x|y)=(p(y|x)*p(x))/p(y)</a></li><li>4. <a href="http://en.wikipedia.org/wiki/Phrase_structure_rule">S -> NP VP</a></li></ul></div><div style="text-align: left;">However, for some strange reason, people who think human language doesn't require rules, <i>only</i> mean rules like (4) - rules 1-3 (and, arguably, infinitely many more) are not just ok, they're often required.</div><div style="text-align: left;">
</div><div style="text-align: left;">Of course, there is a bigger question: can (4) be re-stated in a different system of rules? Probably. But, to take an example from physics, the Newtonian </div><div style="text-align: left;"><a href="http://en.wikipedia.org/wiki/Newton%27s_laws_of_motion#Newton.27s_second_law">F = m.a</a> </div><div style="text-align: left;">does a fantastic job for most of our daily purposes; although we now "know" that the correct (relativistic) form is: </div><div style="text-align: left;"><a href="http://en.wikipedia.org/wiki/Special_relativity#Force">F = m. (d(</a><span class="Apple-style-span" style=" line-height: 19px; font-family:sans-serif;font-size:13px;"><a href="http://en.wikipedia.org/wiki/Special_relativity#Force">γ</a></span><a href="http://en.wikipedia.org/wiki/Special_relativity#Force">.v)/dt)</a></div><div style="text-align: left;">
</div><div style="text-align: left;">So, till those computationalists who deny rules like (4) can give us a better rule system with the kind of intra- and inter-language advances made by assuming variants of (4), it just remains a promissory note with limited substance.</div><div style="text-align: left;">
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</div><div class="blogger-post-footer"><p>_Moss<img src="http://mohinish.s.googlepages.com/mossicon.png" alt="moss" width="16" height="16" /><img src="http://mohinish.s.googlepages.com/feed-icon-16x16.png" alt="feed" width="16" height="16" />Feed_</p></div>mohinishhttp://www.blogger.com/profile/07121978396381676854noreply@blogger.com0tag:blogger.com,1999:blog-26945663.post-3370863671037918942010-10-06T00:06:00.009+02:002010-10-06T00:42:24.995+02:00Matlab boxplot notch "error" resolved<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjsvyL1c5ivu8Ne3bGWxrNRbzdshHubUUfeWUoZRyo0Ttv-kqdsLk-TqL8CAVG1St5fUqkOjqQkAmn0glN4Et9YJWZiLb0QIWAwlZXvxzyur9rLX2niCuMQcTMvkNRMWi9RQFpBqg/s1600/boxplotMPG.png"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 320px; height: 240px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjsvyL1c5ivu8Ne3bGWxrNRbzdshHubUUfeWUoZRyo0Ttv-kqdsLk-TqL8CAVG1St5fUqkOjqQkAmn0glN4Et9YJWZiLb0QIWAwlZXvxzyur9rLX2niCuMQcTMvkNRMWi9RQFpBqg/s320/boxplotMPG.png" border="0" alt="" id="BLOGGER_PHOTO_ID_5524695999100063202" /></a>
<div>Use Matlab? Try this:</div><div><div><span class="Apple-style-span" style=" white-space: pre; font-family:'courier new', courier, monospace;"><span class="Apple-style-span" style="font-size:small;">>> load carsmall</span></span></div><div><span class="Apple-style-span" style="font-size:small;"><span class="Apple-style-span" style=" white-space: pre; font-family:'courier new', courier, monospace;"></span></span><span class="Apple-style-span" style=" white-space: pre; font-family:'courier new', courier, monospace;"><span class="Apple-style-span" style="font-size:small;">>> boxplot(MPG,Origin,'notch','on')</span></span></div><div>
</div><div><span class="Apple-style-span" style=" white-space: pre; font-family:'courier new', courier, monospace;font-size:12px;"></span>See something weird? Something that looks like this image with the boxes folded over? It's been driving me crazy for a while; I thought I'd broken Matlab somehow; till I discovered this <a href="http://www.mathworks.com/help/toolbox/stats/rn/brmpzlp.html">little documentation</a>. Essentially, before R2008b, the notches were truncated to the edges of the box. Since that's wrong, in the sense that the notches (robust estimates of the median) could extend beyond the box edges, Matlabbers fixed this, so now the notches go to wherever they please; but sometimes it makes the figures look weird.</div><div>
</div><div>From the Mathworks website: </div><div><span class="Apple-style-span" style=" ;font-family:Verdana, Arial, Helvetica, sans-serif;font-size:11px;"><ul type="disc" style="margin-top: 10px; margin-right: 0px; margin-bottom: 10px; margin-left: 16px; list-style-type: square; list-style-image: url(http://www.mathworks.com/images/bullet_purp.gif); padding-top: 0px; padding-bottom: 0px; padding-right: 0px; padding-left: 0px; "><li style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><p style="margin-top: 10px; margin-right: 0px; margin-bottom: 10px; margin-left: 0px; font-family: Verdana, Arial, Helvetica, sans-serif; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; ">For small groups, the <tt style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font-family: 'courier new', courier, monospace; font-size: 12px; ">'notch'</tt> parameter sometimes produces notches that extend outside of the box. In previous releases, the notch was truncated to the extent of the box, which could produce a misleading display. A new value of <tt style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font-family: 'courier new', courier, monospace; font-size: 12px; ">'markers'</tt> for this parameter avoids the display issue.</p></li></ul><p style="margin-top: 10px; margin-right: 0px; margin-bottom: 10px; margin-left: 0px; font-family: Verdana, Arial, Helvetica, sans-serif; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; "></p><p style="margin-top: 10px; margin-right: 0px; margin-bottom: 10px; margin-left: 0px; font-family: Verdana, Arial, Helvetica, sans-serif; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; ">As a consequence, the <a href="http://www.mathworks.com/help/toolbox/stats/anova1.html" style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; color: rgb(0, 43, 199); text-decoration: none; "><tt style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font-family: 'courier new', courier, monospace; font-size: 12px; ">anova1</tt></a> function, which displays notched box plots for grouped data, may show notches that extend outside the boxes.</p></span></div><div>For comparison, the second figure is how boxplot used to work.</div><div>
</div></div><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjXYPYLfZeLPhNyKXqWWXd4ajECv8ak3GFGZ1_5tuKmyPupZx7i5zsMLHztAxx9JTBAD19wQFd3c5HMcS9aTvbCPTHGe1-TnW1HO8SWKcmtQje1HJh_kYIGoqVbUvmOWhc_0_cbwA/s1600/oldmpg.png"><img style="float:left; margin:0 10px 10px 0;cursor:pointer; cursor:hand;width: 320px; height: 240px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjXYPYLfZeLPhNyKXqWWXd4ajECv8ak3GFGZ1_5tuKmyPupZx7i5zsMLHztAxx9JTBAD19wQFd3c5HMcS9aTvbCPTHGe1-TnW1HO8SWKcmtQje1HJh_kYIGoqVbUvmOWhc_0_cbwA/s320/oldmpg.png" border="0" alt="" id="BLOGGER_PHOTO_ID_5524694334968150546" /></a><div class="blogger-post-footer"><p>_Moss<img src="http://mohinish.s.googlepages.com/mossicon.png" alt="moss" width="16" height="16" /><img src="http://mohinish.s.googlepages.com/feed-icon-16x16.png" alt="feed" width="16" height="16" />Feed_</p></div>mohinishhttp://www.blogger.com/profile/07121978396381676854noreply@blogger.com57tag:blogger.com,1999:blog-26945663.post-86806015032222440142010-09-26T21:04:00.016+02:002010-09-26T23:14:46.080+02:00The question of dumb rats (and smart babies)<div><i><span class="Apple-style-span" style="font-family:georgia;">Some scientists seem to believe that rats predicting when the next foot shock happens is all we need to know to understand how babies learn language. Should you?</span></i></div><div><span class="Apple-style-span" style="font-family:georgia;">
</span></div><span class="Apple-style-span" style="font-family:georgia;"><span class="Apple-tab-span" style="white-space:pre"> </span>I came across </span><a href="http://scientopia.org/blogs/childsplay/2010/09/23/dumberthanarat/"><span class="Apple-style-span" style="font-family:georgia;">an interesting blog post</span></a><span class="Apple-style-span" style="font-family:georgia;"> that is essentially more anti-Chomsky/Pinker rhetoric. It seems that some baby research likes to throw its little subjects out with their clichés, to describe «new and revolutionary ways» in thinking about language. So here is some attempt to restore balance to the universe.</span><div><span class="Apple-style-span" style="font-family:georgia;">
</span></div><div><span class="Apple-style-span" style="font-family:georgia;">The general line from that blog is something like this:</span></div><div><span class="Apple-style-span" style="font-family:georgia;">(1) Lack of negative evidence is critical to ChomskyPinkerian's position that there must be innate constraints on language acquisition.</span></div><div><span class="Apple-style-span" style="font-family:georgia;">(2) In a tone-shock associative task, rats are sensitive to the statistical pattern of presence </span><i><span class="Apple-style-span" style="font-family:georgia;">and</span></i><span class="Apple-style-span" style="font-family:georgia;"> absence of the tone, and learn to predict the shock based on (what she calls) positive and negative evidence.</span></div><div><span class="Apple-style-span" style="font-family:georgia;">(3) Since rats can learn arbitrary relationships from such negative evidence, why do ChomskyPinkerians believe babies cannot, and instead invoke innate constraints? (followed by some wrist-slapping).</span></div><div><span class="Apple-style-span" style="font-family:georgia;">
</span></div><div><span class="Apple-style-span" style="font-family:georgia;"><span class="Apple-tab-span" style="white-space:pre"> </span>First of all, notice that the example is rotten - this is not the sense of negative evidence that's relevant at all. This is just saying that rats are sensitive to the probability of a shock given a tone. In the "negative example" case, it's just that the conditional probability p(shock|tone) is less than 1.0</span></div><div><span class="Apple-style-span" style="font-family:georgia;">
</span></div><div><span class="Apple-style-span" style="font-family:georgia;"><span class="Apple-tab-span" style="white-space:pre"> </span>The lack of negative evidence is a logical argument that's quite ridiculously simple: given finite data, you cannot deduce the true underlying generative system. Therefore, if all you're exposed to is a finite set of sentences, you cannot infer the true underlying (generative grammatical) system, unless you have </span><i><span class="Apple-style-span" style="font-family:georgia;">something</span></i><span class="Apple-style-span" style="font-family:georgia;"> that guides you to the right solution space.</span></div><div><span class="Apple-style-span" style="font-family:georgia;">
</span></div><div><span class="Apple-style-span" style="font-family:georgia;"><span class="Apple-tab-span" style="white-space:pre"> </span>But you don't have to believe me when I say it's hard - look at the simple evidence: even with several bazillion sentences at our disposition, and all the fancy computational tools, no one has yet come up with an adequate description of a generative system that will produce all and only grammatical English sentences.</span></div><div><span class="Apple-style-span" style="font-family:georgia;">
</span></div><div><span class="Apple-style-span" style="font-family:georgia;"><span class="Apple-tab-span" style="white-space:pre"> </span>But a 5-year-old </span><i><span class="Apple-style-span" style="font-family:georgia;">does</span></i><span class="Apple-style-span" style="font-family:georgia;"> end up knowing the generative system, and will produce sentences you sometimes wish she wouldn't, and will write little stories, making original sentences that she couldn't possibly have just overheard anywhere.</span></div><div><span class="Apple-style-span" style="font-family:georgia;">
</span></div><div><span class="Apple-style-span" style="font-family:georgia;"><span class="Apple-tab-span" style="white-space:pre"> </span>That is roughly the argument for why there must be something inside the baby that makes it such a genius at figuring out how the language system works. And this something (let's call it </span><i><a href="http://www.bendyglu.domainepublic.net/archives/chomsky%20reader/FitchHauserChomksyLangFacCog.pdf"><span class="Apple-style-span" style="font-family:georgia;">Flynn</span></a></i><span class="Apple-style-span" style="font-family:georgia;">) is (part of) the reason why human babies, but not rat babies or komodo dragon babies or little guppies, end up learning language.</span></div><div><span class="Apple-style-span" style="font-family:georgia;">
</span></div><div><span class="Apple-style-span" style="font-family:georgia;"><span class="Apple-tab-span" style="white-space:pre"> </span>Does this mean there cannot be any general cognitive principles? Of course not, and no one claims there cannot be or that they don't affect language learning (that would be the </span><i><span class="Apple-style-span" style="font-family:georgia;">Flab</span></i><span class="Apple-style-span" style="font-family:georgia;">). What they are and how they do their job is an empirical question. Saying something is innate is merely a description - it doesn't tell you </span><i><span class="Apple-style-span" style="font-family:georgia;">how</span></i><span class="Apple-style-span" style="font-family:georgia;"> the system works; that's what keeps researchers in business. </span></div><div><span class="Apple-style-span" style="font-family:georgia;">
</span></div><div><span class="Apple-style-span" style="font-family:georgia;"><span class="Apple-tab-span" style="white-space:pre"> </span>And coming to negative evidence, here's a fantastic quote from Roger Brown et al (quoted in Dan Slobin's </span><i><span class="Apple-style-span" style="font-family:georgia;">Psychlinguistics</span></i><span class="Apple-style-span" style="font-family:georgia;">):</span></div><div><span class="Apple-style-span" style="font-family:georgia;">
</span></div><div><span class="Apple-style-span" style="font-family:georgia;"><p style="margin: 5.0px 0.0px 0.0px 0.0px; font: 12.0px Helvetica">What circumstances did govern approval and disapproval directed at child utterances by parents? Gross errors of word choice were sometimes corrected, as when Eve said <i>What the guy idea</i>. Once in a while an error of pronunciation was noticed and corrected. Most commonly, however, the grounds on which an utterance was approved or disapproved ... were not strictly linguistic at all. When Eve expressed the opinion that her mother was a girl by saying <i>He a girl</i> mother answered <i>That's right</i>. The child's utterance was ungrammatical but mother did not respond to the fact; instead she responded to the truth value of the proposition the child intended to express. In general the parents fit propositions to the child's utterances, however incomplete or distorted the utterances, and then approved or not, according to the correspondence between the proposition and reality. Thus <i>Her curl my hair</i> was approved because mother was, in fact, curling Eve's hair. However, Sarah's grammatically impeccable <i>There's the animal farmhouse</i> was disapproved because the building was a lighthouse and Adam's <i>Walt Disney comes on, on Tuesday</i> was disapproved because Walt Disney comes on, on some other day. It seems then, to be truth value rather than syntactic well-formedness that chiefly governs explicit verbal reinforcement by parents. Which render mildly paradoxical the fact that the usual product of such a training schedule is an adult whose speech is highly grammatical but not notably truthful (Brown, Cazden, and Bellugi, 1967, pp. 57-58).</p></span></div><div><span class="Apple-style-span" style="font-size:medium;"><span class="Apple-style-span" style="font-family:georgia;"></span></span><p></p></div><div class="blogger-post-footer"><p>_Moss<img src="http://mohinish.s.googlepages.com/mossicon.png" alt="moss" width="16" height="16" /><img src="http://mohinish.s.googlepages.com/feed-icon-16x16.png" alt="feed" width="16" height="16" />Feed_</p></div>mohinishhttp://www.blogger.com/profile/07121978396381676854noreply@blogger.com1tag:blogger.com,1999:blog-26945663.post-46164541975202797502010-07-30T21:07:00.009+02:002010-07-30T21:55:14.845+02:00PRAAT script to extract sound tokens<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEha7P1jyh0wl1MUD3D-u9uCLR_vzET1HBhWpzYWWhejz0_Gcw0HpFnqtHmj6oBKc5Fu5fnpdnYJzfLEzWqjGt756tXmiBntjmvjFGkokGkMvUi_j0WgDM5TbiEiGaJW080as5k6IQ/s1600/soundslices.png"><img style="float:center; margin:0 10px 10px 0;cursor:pointer; cursor:hand;width: 320px; height: 287px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEha7P1jyh0wl1MUD3D-u9uCLR_vzET1HBhWpzYWWhejz0_Gcw0HpFnqtHmj6oBKc5Fu5fnpdnYJzfLEzWqjGt756tXmiBntjmvjFGkokGkMvUi_j0WgDM5TbiEiGaJW080as5k6IQ/s320/soundslices.png" border="0" alt="" id="BLOGGER_PHOTO_ID_5499786599712510178" /></a><h2>The problem:</h2><div>You have recorded a single long sound file with many tokens (words, syllables), separated by silence for your fantastic upcoming experiment. You want to now segment the long recording and extract each of the tokens into separate sound files.</div><div>
</div><div><h2>The solution:</h2></div><div>My <a href="https://docs.google.com/uc?id=0B-BDyswjlDEfMzRjYWZlZWEtYTc3MS00MmFjLTljZWEtMzkyNzlkZDNkOGE0&export=download&authkey=CPuJ8agB&hl=en">GetNonSilenceBitsinDir</a> script in <a href="http://www.fon.hum.uva.nl/praat/">PRAAT</a>!</div><div>
</div><div><h2>How to use:</h2></div><div>Place this with all your other favorite scripts. Save all your recordings in a single directory. To be safe, put copies of all your recordings in a single directory. Load up PRAAT and run the script.</div><div>
</div><div><h2>Notes</h2></div><div><ol><li>The script also ensures that each of the sound files extracted have zero crossings at the beginning and end, so things sound good.</li><li>You might have to play around with the parameters for what constitutes silence. Search for the "#" line in the script and modify the parameters in the following line. Look up help on <b><i>Sound: To TextGrid (silences)...</i></b> in the PRAAT help.</li></ol>
</div><div class="blogger-post-footer"><p>_Moss<img src="http://mohinish.s.googlepages.com/mossicon.png" alt="moss" width="16" height="16" /><img src="http://mohinish.s.googlepages.com/feed-icon-16x16.png" alt="feed" width="16" height="16" />Feed_</p></div>mohinishhttp://www.blogger.com/profile/07121978396381676854noreply@blogger.com2tag:blogger.com,1999:blog-26945663.post-28305689188404931142009-12-23T17:02:00.011+01:002010-10-03T20:29:08.745+02:00Primates and walkingIn a previous issue of the lovely journal <i><a href="http://www.mindfields.in/index.htm">Mindfields</a></i>, I wrote an article about <a href="http://www.mindfields.in/MF02/mf2-demystifying-science.htm">baby robots</a>. In this, happily ignoring various dynamical systems approaches to the issue, I wrote:<div><blockquote>Do we think that the ability to walk comes out of experience? Clearly not. It’s not like the human newborn, upon encountering flattish surfaces, gravity, friction, two (semi-)controllable limbs extending below the waist and other similar-looking beings walking around, figures out <i>from scratch</i> that putting this limb so, and then the other one so (controlling for any number of external factors), it can walk. Instead, walking seems to follow its own developmental program, just like facial hair, zits, breasts and those curious feelings for members of a certain gender. So, typically, you cannot walk when you are two months of age, and people around you would be very worried if you were <i>not</i> walking by the age of three.</blockquote></div><div>Just to be clear, this contrasts with dynamical systems in a deep way, as this quote from a random article* shows:</div><div><blockquote>Dynamical systems theory, as we prefer, views walking as an emergent behavior that arises from the collective dynamics of all contributing subsystems, including the central nervous system and musculoskeletal system. Other constraints, such as those found in the environment (e.g., gravitational forces, slippery walking surfaces) and the task itself (e.g., walking fast or slow), also contribute to shaping the behavior.</blockquote></div><div>Note that these authors contrast this with versions of "maturational and neurophysiological approaches." In the most radical version of this stance, something like walking is not pre-destined, but arises through an interaction between various sub-systems. That is, walking is not something that the organism "knows" in any sense of the word, but is a novel generation by each individual (see e.g., Lewkowicz & Lickliter's <a href="http://www.mitpressjournals.org/doi/pdf/10.1162/jocn.1995.7.4.512?cookieSet=1">review</a> of the Thelen & Smith book**).</div><div>
</div><div>Now there are other reasons to suspect that walking and the like <i>are</i> indeed things that (certain) animals can look forward to. For example, pigeons who are restrained from birth can still fly.</div><div>
</div><div>(There's also an interesting salamander story for another day)</div><div>
</div><div>But the new issue of the PNAS has <a href="http://www.pnas.org/content/106/51/21889.abstract?etoc">yet another interesting story</a> to tell. </div><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgFddOisaw95phoTbuUbtQrYemU9XJFuZY0vjAUK1Qluh8-eR5orm8MvZoBKVDtE7WsofFj2nQl253i6TAhqiwCZ0kSG40uxAsLICY-5pyUz4mlFF2qTgdhbew4xljdGM3xRhWUQw/s1600-h/walking.png"><img style="float:left; margin:0 10px 10px 0;cursor:pointer; cursor:hand;width: 237px; height: 320px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgFddOisaw95phoTbuUbtQrYemU9XJFuZY0vjAUK1Qluh8-eR5orm8MvZoBKVDtE7WsofFj2nQl253i6TAhqiwCZ0kSG40uxAsLICY-5pyUz4mlFF2qTgdhbew4xljdGM3xRhWUQw/s320/walking.png" border="0" alt="" id="BLOGGER_PHOTO_ID_5418472750017097362" /></a><div>
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</div><div>*Jane E. Clark and Sally J. Phillips (1993) A Longitudinal Study of Intralimb Coordination in the First Year of Independent Walking: A Dynamical Systems Analysis. <i>Child Development</i>, Vol. 64(4), pp. 1143-1157</div><div>**Esther Thelen and Linda B. Smith (1994) <i>A dynamic systems approach to the development of cognition and action</i>. The MIT Press, Cambridge, MA </div><div class="blogger-post-footer"><p>_Moss<img src="http://mohinish.s.googlepages.com/mossicon.png" alt="moss" width="16" height="16" /><img src="http://mohinish.s.googlepages.com/feed-icon-16x16.png" alt="feed" width="16" height="16" />Feed_</p></div>mohinishhttp://www.blogger.com/profile/07121978396381676854noreply@blogger.com0tag:blogger.com,1999:blog-26945663.post-76032359467487554372009-12-12T16:52:00.008+01:002009-12-12T17:48:11.052+01:00Why a watched pot never boils<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhuhBBuGovF-eTzEqO8QNyGqT4NTUmTqjqGwBjCAY3fVXTpbWV_2Gj-FbCTL3VkaromRlzXzjb77jdFOwefmZJGmfb4YCwsrLh5T_UcbXjA_g4cl2RJW5jpK7hDLzmdgG7_-J80TQ/s1600-h/boiling.png"><img style="float:left; margin:0 10px 10px 0;cursor:pointer; cursor:hand;width: 320px; height: 240px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhuhBBuGovF-eTzEqO8QNyGqT4NTUmTqjqGwBjCAY3fVXTpbWV_2Gj-FbCTL3VkaromRlzXzjb77jdFOwefmZJGmfb4YCwsrLh5T_UcbXjA_g4cl2RJW5jpK7hDLzmdgG7_-J80TQ/s320/boiling.png" border="0" alt="" id="BLOGGER_PHOTO_ID_5414385585224479138" /></a>Simple answer: phase transitions are relatively rapid.<div>
</div><div>Let the time when you set the pot/kettle on the fire to be t_0. </div><div>Let the time when the contents are at a rolling boil be t_b.</div><div>
</div><div>Imagine you're watching TV, and going to the kitchen every once in a while to watch if the contents are actually boiling...</div><div>
</div><div>The essence of the observation is that, given the rapidness of a phase transition, in this case between the non-boiling and the boiling phases, the most likely observation is either one or the other, as shown in this mockchart: only in the pink-magenta region will you actually see the transition from one state to the next.</div><div>
</div><div>So, in all the 'n' trips where t_n is less than the lower bound of the pink-magenta region, the pot won't be boiling. And if you miss the narrow transition window, then on the (n+1)th trip, where t_(n+1) is beyond the pink-magenta region, you'll see the water boiling. And conclude, "a watched pot never boils."<div>
</div><div>That or the <a href="http://en.wikipedia.org/wiki/Quantum_Zeno_effect">Quantum Zeno effect</a>...</div></div><div class="blogger-post-footer"><p>_Moss<img src="http://mohinish.s.googlepages.com/mossicon.png" alt="moss" width="16" height="16" /><img src="http://mohinish.s.googlepages.com/feed-icon-16x16.png" alt="feed" width="16" height="16" />Feed_</p></div>mohinishhttp://www.blogger.com/profile/07121978396381676854noreply@blogger.com1tag:blogger.com,1999:blog-26945663.post-53650918469818857352009-11-13T14:27:00.011+01:002009-12-13T22:24:11.223+01:00Teh<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiaXdquSLOy_WogmnuJcQKwAPE76HIP5FVEMazCLmFiE696W0HjecJnt26fIzq3gST0RsjhdtserunYv5eTTWEmsfgEVHadUhFwLjFoAmfTCZ7Sqr1o9ReWYdopzWPjLV7uvromNw/s1600-h/the.png"><img style="float:left; margin:0 10px 10px 0;cursor:pointer; cursor:hand;width: 249px; height: 173px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiaXdquSLOy_WogmnuJcQKwAPE76HIP5FVEMazCLmFiE696W0HjecJnt26fIzq3gST0RsjhdtserunYv5eTTWEmsfgEVHadUhFwLjFoAmfTCZ7Sqr1o9ReWYdopzWPjLV7uvromNw/s320/the.png" border="0" alt="" id="BLOGGER_PHOTO_ID_5414785387524768674" /></a>I'm sorely vexed with 'teh'. <div>
</div><div>For those who think that frequency is teh everything, here is a conundrum inside an enigma: what explains the frequency of 'teh'?</div><div>
</div><div>The graph shows the log frequency for all the possible 2-letter mixups possible starting from 'the'. Ok, ignore the last one. </div><div>
</div><div>Note that 'teh' is not only the most common, it's the only one where the entire first page of results is about 'teh' as it relates to 'the'. For the last two, the first page hits had nothing to do with 'the'.</div><div><div><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiVChghB1ZXK71-K5Nty619dyDFz4vIkB5KDOhVbyZroPw5S4dtrzuqanF8YZ5T3tnjDpV2o8FKCjHR0KoH6aS7afYoDWARnAehqEh02E_Zrb8BzxavY9H7g8QSzJPgvSIDxL7eIQ/s1600-h/and.png"><img style="float:left; margin:0 10px 10px 0;cursor:pointer; cursor:hand;width: 284px; height: 176px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiVChghB1ZXK71-K5Nty619dyDFz4vIkB5KDOhVbyZroPw5S4dtrzuqanF8YZ5T3tnjDpV2o8FKCjHR0KoH6aS7afYoDWARnAehqEh02E_Zrb8BzxavY9H7g8QSzJPgvSIDxL7eIQ/s320/and.png" border="0" alt="" id="BLOGGER_PHOTO_ID_5414788292631397666" /></a><div>Now consider 'and'. The comparable graph shows decreasing frequency like for 'the', but in this case, none of the 2-letter mistakes have anything to do with 'and' - all the hits on page 1 are various abbreviations.</div><div>
</div>So why is 'teh', as a misspelling (deliberate or otherwise) of 'the' so common? </div><div>
</div><div>One possibility is that the bigram frequencies - TE or EH are way higher than TH or HE (well, probably not the latter).
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</div><div>The other possibility is motor planning and the layout of the qwerty keyboard - do people using other layouts like <a href="http://en.wikipedia.org/wiki/Dvorak_Simplified_Keyboard">Dvorak</a> or <a href="http://en.wikipedia.org/wiki/Colemak#Colemak">Colemak</a> show the same pattern? Other language layouts (maybe with bilinguals)?</div><div>
</div><div>At the very least, it seems that frequency ALONE can never be an answer for stuff you see around you ;)</div><div>
</div></div></div><div class="blogger-post-footer"><p>_Moss<img src="http://mohinish.s.googlepages.com/mossicon.png" alt="moss" width="16" height="16" /><img src="http://mohinish.s.googlepages.com/feed-icon-16x16.png" alt="feed" width="16" height="16" />Feed_</p></div>mohinishhttp://www.blogger.com/profile/07121978396381676854noreply@blogger.com0tag:blogger.com,1999:blog-26945663.post-44097851442425704622009-08-01T19:25:00.004+02:002009-08-04T12:56:19.426+02:00Probability of finding a four-leaf clover<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjfN6C3fYmN4HGQBKwehKIbdwng-Qm3DjuuFw1sscpGvNMH616hiCRM1PNmhCLkFkgbeucUd-xL6VeUC4QXW93nUQkO20fYEcrzSglZwH6dRhe1xsmL1XuUGwJ-G0qC_A2xualD8w/s1600-h/4fourleafs.png"><img style="float:left; margin:0 10px 10px 0;cursor:pointer; cursor:hand;width: 400px; height: 361px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjfN6C3fYmN4HGQBKwehKIbdwng-Qm3DjuuFw1sscpGvNMH616hiCRM1PNmhCLkFkgbeucUd-xL6VeUC4QXW93nUQkO20fYEcrzSglZwH6dRhe1xsmL1XuUGwJ-G0qC_A2xualD8w/s400/4fourleafs.png" border="0" alt="" id="BLOGGER_PHOTO_ID_5365047839736349698" /></a>Short answer: around 1 in 2,000.<div>(<span class="Apple-style-span" style="font-style: italic;">Clarification</span>: this is the probability that, if you pick up a single leaf at random, it will have four leaflets.)
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<div>Here is my collection of four four-leaf clovers (out of five, the fifth has shredded leaves), collected over a period of two weeks. <div>
</div><div>If you look at the <a href="http://en.wikipedia.org/wiki/Four-leaf_clover">wikipedia page</a> (& refs therein), the most commonly cited figure is 1 in 10,000. Unfortunately there are no actual observations reported anywhere.</div><div>
</div><div> But now I can report that, according to my very empirical research, the probability of finding a four-leaf clover is probably more like 1 in 2,000. </div><div><span class="Apple-style-span" style="font-size:medium;"><h2>How do I know?</h2></span></div><div><ol><li>I find that I can scan around 100 plants per minute.</li><li>Most recently, I found two four-leafs in about 30min worth of scanning.</li><li>This gives a rate of 1 in 1,500</li></ol></div><div>The previous attempts have however been slightly longer, although I didn't time them as accurately. Also, the actual number of plants scanned per minute can vary due to wandering attention. So, I would think a more conservative estimate is ~1 in 2,000.</div><div>
</div><div>Of course, these are all in upstate NY, although not at a single location. Perhaps these rates vary with a whole bunch of other factors. </div><div>
</div><div>Still, these are fairly low odds - finding 5 four-leaf clovers, even with these better estimates, is still less than one in 10 quadrillion! (<span class="Apple-style-span" style="font-style: italic; ">Clarification again</span>: this is the probability that, if you pick five leafs blindly, all five will have four leaflets each.)</div></div></div></div><div class="blogger-post-footer"><p>_Moss<img src="http://mohinish.s.googlepages.com/mossicon.png" alt="moss" width="16" height="16" /><img src="http://mohinish.s.googlepages.com/feed-icon-16x16.png" alt="feed" width="16" height="16" />Feed_</p></div>mohinishhttp://www.blogger.com/profile/07121978396381676854noreply@blogger.com5tag:blogger.com,1999:blog-26945663.post-60499667403044849182009-07-25T14:17:00.006+02:002009-07-25T16:52:58.135+02:00Innovations: Segway to languageA signboard on my way home: "High-tech gadgets repaired."<div>
</div><div>What really is a high-tech gadget anyhow? Take the <a href="http://en.wikipedia.org/wiki/Segway_PT">Segway</a>. Nothing like it existed before it did. It would be hard to argue that this was not a genuine innovation - and a reasonably high-tech one.</div><div>
</div><div>But what makes it high-tech and an innovation at all? Certainly, as <a href="http://www.tlb.org/scooter.html">this gentleman shows</a>, it isn't stuff like the "brushless servo motors with neodymium magnets" or wheels of "sophisticated engineering-grade thermoplastic." </div><div>
</div><div>That is, all the parts pre-existed, and can be replaced by equivalent, crappier parts that in themselves are old hat, and aren't necessary for the innovation itself. </div><div>
</div><div>What about the software? Well, it's using some version of C or Python or some such. So that's not new. Neither is the general problem, which as Wikipedia tells me, is that of the <a href="http://en.wikipedia.org/wiki/Inverted_pendulum">inverted pendulum</a>.</div><div>
</div><div>So why is the Segway an innovation? And really, is it even an innovation at all? I think you might agree that, in a sense it is. Oh sure, maybe someone else thought of the idea before and never got around to implementing it, but as far we know, <a href="http://en.wikipedia.org/wiki/Dean_Kamen">Dean Kamen</a> invented the Segway.</div><div>
</div><div>Now here's the point - I think it's the same deal with language and cognition. Sure, language might rely on a whole bunch of stuff - the cognitive equivalent of neodymium magnets and thermoplastics, but in the end, I believe that it is a genuine innovation like the Segway is. </div><div>
</div><div>Look at what the Segway relies on (/is made up of), and you find that all the pieces pre-exist, and can be found in several other, crappier devices that don't do half as much. Look at the code, and you'll find data structures and operators from the simplest "Hello World" program. Similarly, look at what language relies on (/is made up of), and you'll find the same old cognitive systems like memory and attention and, I wouldn't be surprised, sex, drugs & rock'n'roll; cos those are the bits the mind is made up of anyway.</div><div>
</div><div>But nevertheless, like the Segway is an invention of Dean Kamen, language is an innovation of our species. So the next time you read a paper that pretends that language is nothing more than memory or attention, think of the Segway. </div><div>
</div><div class="blogger-post-footer"><p>_Moss<img src="http://mohinish.s.googlepages.com/mossicon.png" alt="moss" width="16" height="16" /><img src="http://mohinish.s.googlepages.com/feed-icon-16x16.png" alt="feed" width="16" height="16" />Feed_</p></div>mohinishhttp://www.blogger.com/profile/07121978396381676854noreply@blogger.com1tag:blogger.com,1999:blog-26945663.post-11497309620465649932009-07-22T22:25:00.006+02:002009-11-13T14:29:13.804+01:00Or, who has seen the wind?<div>Finally the special issue is out, and it looks like balance, intelligence, a broad biological perspective and just plain good reading habits lose to rhetoric, misrepresentation and... and I really do not know what.</div><div>
</div><div>The culprit, which I think is possibly one of the worst articles is by <a href="http://www3.interscience.wiley.com/journal/122513541/abstract">Spencer et al</a>, and is the first in a special section: Is It Time to Look Beyond the Nativist–Empiricist Debate? in the <a href="http://www3.interscience.wiley.com/journal/118492257/home">August issue (Vol. 3,No. 2) of Child Development Perspectives</a>. </div><div>
</div><div>The point of the paper is hard to understand, given that, I think, most nativists would have no problems with most or any of the examples they give. Why the fact that development "emerges via cascades of interactions across multiple levels of causation, from genes to environments" should pose a problem for the innateness thesis I cannot fathom. Of <i>course</i>, the adult biological entity is a product of genes and environments. How one can possibly have any kind of theory involving, e.g., nouns and verbs that is derived from such an understanding of development is presumably left as an exercise for the reader.</div><div>
</div><div>Everything, language, cognition - must be grounded in theories of development, in their view. It reminds me of the poem by <a href="http://en.wikipedia.org/wiki/Christina_Rossetti">Christina Rossetti</a>:</div><div></div><blockquote><div>Who has seen the wind?
Neither I nor you.
But when the leaves hang trembling,
The wind is passing through.
Who has seen the wind?
Neither you nor I.
But when the trees bow down their heads,
The wind is passing by.
</div><div></div></blockquote><div>The point is, and this is probably not the best way to make the point, that "wind" is not really something you can see, just as "language" is not something you can see. You call the (generative) force that hurries leaves along "wind", just as you call the mechanism that drives words from your lips "language". Grounded, whether in the sense of Spencer et al, or grounded in the sense of <a href="http://en.wikipedia.org/wiki/Embodied_cognition">embodied cognition</a>, I find it these conflations of various interlocking questions: what is a good theory of the generative systems (the <i>langue</i>) that propel the various specific instances, heard and unheard (the <i>parole</i>)? How does this come to be? In ontogeny? In phylogeny? </div><div>
</div><div>It seems to me that there is one main reason for writing this paper- the various 'critics' seem to think that, if something is identified as "innate", then research stops. Perhaps so, but that depends entirely on the level at which one is researching. If I am studying comparative behavior, then I might be content to report that: </div><div>(1) Chickadees can be tamed in adulthood, while almost no other passerine can. </div><div>Does this come out of a "complex interaction of genes and environment?" Undoubtedly?! But does it make a statement like (1) something no researcher should abide by? Well, not for me.</div><div>
</div><div>Will the elaborate and "inconvenient" (in their case meaning [1] complex or [2] amenable to much broader range of phenotypes than those the typical environments allow) developmental research shed any immediate light on, e.g., why we can understand and explain to someone the rules of chess? Personally, I'd put that question on par with a quantum theory of tectonic plate movements.</div><div>
</div><div>Maybe it's a lack of exposure to Fry & Laurie at some critical stage ;)</div><object width="340" height="285"><param name="movie" value="http://www.youtube.com/v/hHQ2756cyD8&hl=en&fs=1&rel=0&color1=0x3a3a3a&color2=0x999999&border=1"><param name="allowFullScreen" value="true"><param name="allowscriptaccess" value="always"><embed src="http://www.youtube.com/v/hHQ2756cyD8&hl=en&fs=1&rel=0&color1=0x3a3a3a&color2=0x999999&border=1" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="340" height="285"></embed></object><div class="blogger-post-footer"><p>_Moss<img src="http://mohinish.s.googlepages.com/mossicon.png" alt="moss" width="16" height="16" /><img src="http://mohinish.s.googlepages.com/feed-icon-16x16.png" alt="feed" width="16" height="16" />Feed_</p></div>mohinishhttp://www.blogger.com/profile/07121978396381676854noreply@blogger.com0tag:blogger.com,1999:blog-26945663.post-91068195654901425142009-05-25T05:01:00.002+02:002009-05-25T05:18:07.204+02:00Backup systems on spaceshipsWatching old Star Trek: Next Generation. In this episode (Disaster) the <span class="Apple-style-span" style="font-style: italic;">Enterprise</span> collides with a quantum filament (whatever that might be), and things aren't very spiffy anymore aboard the vessel. Life support systems are compromised and the field holding the ship together is packing up for a little vacation.<div>
</div><div>Anyhow, that got me thinking - if I were to have any say in the design of a spaceship, I think that besides the various backup systems, fault tolerance, hierarchical, modular structures and self-healing material, to also make sure that for each critical system, there was at least one backup with a <span class="Apple-style-span" style="font-style: italic;">totally different technology</span>. So, for e.g., if a quantum filament hits you and quantum systems are jinxed, you can switch over to a classical system. The fundamental idea being that the <span class="Apple-style-span" style="font-style: italic;">cause</span> of the damaging element would be unlikely to affect two technologies that were fundamentally differently implemented.</div><div>
</div><div>Which nicely brings us back to Marr and his levels :) To restate: the spaceship would benefit if the systems for each critical function (the computational level) was implemented (implementational level) in two distinct ways, so that if something caused a failure of the implementational bits of one system, it would be unlikely to also affect the implementational bits of the second system. </div><div>
</div><div> </div><div class="blogger-post-footer"><p>_Moss<img src="http://mohinish.s.googlepages.com/mossicon.png" alt="moss" width="16" height="16" /><img src="http://mohinish.s.googlepages.com/feed-icon-16x16.png" alt="feed" width="16" height="16" />Feed_</p></div>mohinishhttp://www.blogger.com/profile/07121978396381676854noreply@blogger.com0tag:blogger.com,1999:blog-26945663.post-22954504306805322042009-05-08T15:56:00.002+02:002009-05-08T16:10:15.354+02:00Featured!I got <a href="http://www.psychologicalscience.org/observer/getArticle.cfm?id=2508">featured</a> in the <span class="Apple-style-span" style="font-style: italic;">Observer</span> magazine of the Association for Psychological Science!<div>
</div><div>Also, I realized I haven't really been blogging in a while. Which is not to say there hasn't been anything interesting :)</div><div>
</div><div>
</div><div class="blogger-post-footer"><p>_Moss<img src="http://mohinish.s.googlepages.com/mossicon.png" alt="moss" width="16" height="16" /><img src="http://mohinish.s.googlepages.com/feed-icon-16x16.png" alt="feed" width="16" height="16" />Feed_</p></div>mohinishhttp://www.blogger.com/profile/07121978396381676854noreply@blogger.com0tag:blogger.com,1999:blog-26945663.post-59148257400109740392009-02-15T15:17:00.000+01:002009-02-15T15:21:07.420+01:00iPhone!!Since it's not yet possible to jack into the matrix, at least there's the iPhone :) <br/><br clear="all"/><div class="iblogger-location-wrapper"/>Mobile Blogging from <a class="iblogger-location" href="http://maps.google.com/maps?ll=43.1486,-77.5817">here</a>.</div><div class="iblogger-footer"><br clear="all"/><p style="text-align:right;font-size:10px;">[Posted with <a href="http://illuminex.com/iBlogger/index.html">iBlogger</a> from my iPhone]</p><br/></div>
<div class="blogger-post-footer"><p>_Moss<img src="http://mohinish.s.googlepages.com/mossicon.png" alt="moss" width="16" height="16" /><img src="http://mohinish.s.googlepages.com/feed-icon-16x16.png" alt="feed" width="16" height="16" />Feed_</p></div>mohinishhttp://www.blogger.com/profile/07121978396381676854noreply@blogger.com0tag:blogger.com,1999:blog-26945663.post-16816130325630724542008-12-18T03:14:00.003+01:002008-12-18T03:46:18.066+01:00The plan<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhgdlPx0UwNxbzFTKx9NtvjGsOz6EDUB9X11RcXE9ONmqckGeF0a4PJvzuPMhdppVxyRGJjAvsBAvUeTNFOA9Lo6ojxXLTl6pE6KpCJTtxlKxxCEPW3wEN-FfULGryqGCanrshBUg/s1600-h/tobiiBoard.jpg"><img style="margin: 0px auto 10px; display: block; text-align: center; cursor: pointer; width: 400px; height: 300px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhgdlPx0UwNxbzFTKx9NtvjGsOz6EDUB9X11RcXE9ONmqckGeF0a4PJvzuPMhdppVxyRGJjAvsBAvUeTNFOA9Lo6ojxXLTl6pE6KpCJTtxlKxxCEPW3wEN-FfULGryqGCanrshBUg/s400/tobiiBoard.jpg" alt="" id="BLOGGER_PHOTO_ID_5280955916072518482" border="0" /></a>
Me and Katherine are working on an anticipatory looking paradigm, and we've designed a system for creating and analyzing Tobii experiments. Starting from this system-level design, Johnny Wen has written a most marvelous MATLAB project. It's amazing how far this cluttered-looking whiteboard has come :)<div class="blogger-post-footer"><p>_Moss<img src="http://mohinish.s.googlepages.com/mossicon.png" alt="moss" width="16" height="16" /><img src="http://mohinish.s.googlepages.com/feed-icon-16x16.png" alt="feed" width="16" height="16" />Feed_</p></div>mohinishhttp://www.blogger.com/profile/07121978396381676854noreply@blogger.com0tag:blogger.com,1999:blog-26945663.post-55841555146279642782008-09-13T18:23:00.000+02:002008-09-13T18:24:34.368+02:00I'm a skeptic<p><em>Your result for The What's Your Philosophy? Test...</em></p><h4>Skeptic</h4><p style="text-align:center"><img src="http://is1.okcupid.com/users/626/856/62685721645925622/mt1106176932.jpg" width="" height="" /></p>
<div>The skeptic constantly lives in a state of denial - everything is false until proven otherwise. Skeptics refuse to follow religion, since it relies on theories that cannot be proven true or false. Likewise, they refuse to believe in most scientific research, since logic is viewed as an inadequate measure of truth (Just because A = B, and B = C, there's no proof that A = C). Although they can sometimes be depressing to talk to, skeptics are vital to scientific advancements, since they constantly look for problems with new theories.
Famous skeptics include: David Hume, Rene Descartes.
The opposite of Skepticism is Optimism.
</div><p><a href="http://www.helloquizzy.com/tests/the-whats-your-philosophy-test">Take The What's Your Philosophy? Test</a></p><div class="blogger-post-footer"><p>_Moss<img src="http://mohinish.s.googlepages.com/mossicon.png" alt="moss" width="16" height="16" /><img src="http://mohinish.s.googlepages.com/feed-icon-16x16.png" alt="feed" width="16" height="16" />Feed_</p></div>mohinishhttp://www.blogger.com/profile/07121978396381676854noreply@blogger.com0tag:blogger.com,1999:blog-26945663.post-40513177079380305762008-08-01T03:25:00.005+02:002008-08-01T03:50:15.374+02:00Buddhist monks and post-modernists on a rollercoasterSo, a while ago I go on my first rollercoaster, and as it sends us hurtling to a certain (p < 0.001) death, I spent some time reflecting on physics equations. Followed by that, I paid homage to the sciences of metallurgy, geometry, friction; before moving on to philosophy and theology.
I cannot believe I lived through that. Or that I went on a couple others. And somewhere behind the adrenaline and who-knows-what-other chemicals clouding it, I sat in a corner of my mindbrain reflecting on the reality of what we perceive of as the real world. More specifically, the role of science in all that, as describing a true reality.<div>
</div><div>Thing is, you cannot help <span class="Apple-style-span" style="font-style: italic;">wanting</span> the physics to be a true and very very accurate description of reality. It's all that keeps us in the little metal seats while we twirl and twist at speeds we were not exactly supposed to undergo. So naturally, i wondered what would someone who might object to this version of reality think about going on rollercoasters. </div><div>
</div><div>So, I wondered what (a) a Buddhist monk and (b) a Post-modernist would feel about rollercoasters. I don't know the answer for the post-modernist (<a href="http://en.wikipedia.org/wiki/Jacques_Derrida">Derrida</a> springs to mind), but for the monk, the answer is clear, as Frank Howard pointed out - the <a href="http://en.wikipedia.org/wiki/Madhyamika">Madhyamika</a> style is to analyze the perceived reality as being clear and real as the reality where one lives multiple lifetimes and 'sees' an <a href="http://en.wikipedia.org/wiki/Chenrezig">Avalokitesvara</a> as a tangible presence. For the monk, the distinction itself is not entirely meaningful except as one possible method in attaining enlightenment. </div><div>
</div><div>In short, going on a rollercoaster presents no philosophical contradiction to (certain?) Buddhist monks. I'm not sure what the answer is for the post-modernist.</div><div>
</div><div>
</div><div>
</div><div class="blogger-post-footer"><p>_Moss<img src="http://mohinish.s.googlepages.com/mossicon.png" alt="moss" width="16" height="16" /><img src="http://mohinish.s.googlepages.com/feed-icon-16x16.png" alt="feed" width="16" height="16" />Feed_</p></div>mohinishhttp://www.blogger.com/profile/07121978396381676854noreply@blogger.com0tag:blogger.com,1999:blog-26945663.post-21667609531180909282008-07-11T19:20:00.003+02:002008-07-11T19:41:36.944+02:00IllusiontimeHere's a nice illusion:<div><br /></div><div>Stare at the central dot in the image. </div><div>Wait for the image to switch over to the color-inverted version. Keep staring at the dot.</div><div>Now, when the image switches back, you should see a 'normally' colored picture (the colors might be a bit washed out).</div><div>But! Look around the pic now - it is still a grayscale image!<br /><br /><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg70fxYkT512gFd6BZybEjnrvLgmLnJGE8479CHGybeKSmPk-V7XchuBkdxj6-v8y3v_3fgf4dp2VhXqwyQCfNWoVVOxXUmoojvn6vm3l6cDSJoldJiR19I2rL3hw7M5QA1OkiiAg/s1600-h/door.gif"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;" src="http://lh4.ggpht.com/mohinish.s/SHeZTq-afCI/AAAAAAAAA0A/GT_Fd8nrHBc/door.gif" border="0" alt="" id="BLOGGER_PHOTO_ID_5221811719438858450" /></a></div><div><br /></div><div>How I think it works:</div><div>The reversed-color image causes specific (spatially congruent) bits of the retina to adapt to the color at that point. So, when the inverted-color image goes off, you get a recovery, which is the true color, and that 'paints' the grayscale :)</div><div><br /></div><div><span class="Apple-style-span" style="font-size: x-small;"><span class="Apple-style-span" style="font-style: italic;">(Photo (c) me)</span></span></div><div class="blogger-post-footer"><p>_Moss<img src="http://mohinish.s.googlepages.com/mossicon.png" alt="moss" width="16" height="16" /><img src="http://mohinish.s.googlepages.com/feed-icon-16x16.png" alt="feed" width="16" height="16" />Feed_</p></div>mohinishhttp://www.blogger.com/profile/07121978396381676854noreply@blogger.com1tag:blogger.com,1999:blog-26945663.post-42763139983340858772008-07-10T16:24:00.004+02:002008-07-10T18:21:19.707+02:00Astrocyte ComputingThe term is supposed to parallel 'Neural Computing', and is intended to work out how astrocytes in the brain are capable of doing computations. <div><br /><div></div><div>In the <a href="http://mohinish.blogspot.com/search?q=astrocytes">past</a>, I've wondered about astrocytes in relation to hemodynamics in the brain. The standard (T2*) BOLD response in fMRI is primarily caused by local changes in the OxyHb:DeoxyHb ratio. The assumption has been that this ratio reflects local neural activity, through a coupling between neural activity and blood flow. Other studies have shown that the coupling is largely mediated through astrocytes. </div><div><br /></div><div>But do astrocytes actually perform any computations beyond just recruiting blood flow? Not entirely clear; but a <a href="http://web.mit.edu/msur/www/publications/2008_SchummersYuSur.pdf">new paper</a> from the <a href="http://www.mit.edu/~msur/">Mriganka Sur</a> group shows that astrocytes in the ferret visual cortex have properties similar to neurons.</div><div><br /></div><div>Here are stimulus-dependent fluorescence changes in neurons and astrocytes: Notice that the time scale is comparable- astrocytes are off by just a couple of seconds. Turns out that the astrocytes are also more sharply tuned (e.g., to orientation, in these studies).</div><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh3wV6UbEzO8H0yVc-X-LonA83NtKTiunsSoYhiYrMVkzRS2BjZ5jc494MS1bmBCWU2wGDR3wXjcTybhDsWtFRrc07wMdtj3MzKj7j8X7WlyUnWc1C4FQV6NS4NeL6eVY3qSebXVA/s1600-h/astro.png"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh3wV6UbEzO8H0yVc-X-LonA83NtKTiunsSoYhiYrMVkzRS2BjZ5jc494MS1bmBCWU2wGDR3wXjcTybhDsWtFRrc07wMdtj3MzKj7j8X7WlyUnWc1C4FQV6NS4NeL6eVY3qSebXVA/s400/astro.png" border="0" alt="" id="BLOGGER_PHOTO_ID_5221412663364779026" /></a><br />And another really cool result: the authors add a glutamate transporter antagonist (TBOA). This has the effect of not clearing glutamate from the synaptic cleft. This causes (a) a reduction in the activity of the astrocytes and (b) an increase and prolongation in the activity of neurons due to extra glutamate in the cleft. But, look at what happens to the blood volume change (measured as an intrinsic optical signal at 546-nm): it decreases! </div><div><br /></div><div><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjPg3_yb-73Zvt6cRXjISYQzGXa-CnUqADy-tKF8f61UzvkCQlEPAqW9KXdALkNteOqqX3I2YDNUke4HaKKlvQcfUyPpG1-YVcs3QGQRs66zyixWAdldNnUN7GywOcBNh2It2ChgA/s1600-h/intrinsic.png"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjPg3_yb-73Zvt6cRXjISYQzGXa-CnUqADy-tKF8f61UzvkCQlEPAqW9KXdALkNteOqqX3I2YDNUke4HaKKlvQcfUyPpG1-YVcs3QGQRs66zyixWAdldNnUN7GywOcBNh2It2ChgA/s400/intrinsic.png" border="0" alt="" id="BLOGGER_PHOTO_ID_5221412668630007890" /></a>I.e., although neuronal firing <span class="Apple-style-span" style="font-style: italic;">increases</span>, blood volume change <span class="Apple-style-span" style="font-style: italic;">decreases</span>. Of course, this is in the presence of TBOA, but it makes you wonder if there are physiological conditions under which the glu-transporters are downregulated (perhaps at a different timescale), leading to a decrease in blood-flow changes.</div><div><br /></div><div>Of course, blood-flow and BOLD are themselves not super-directly related. But what these studies show is that hemodynamic measures might be actually capturing astrocyte activity, rather than neural activity.</div><div><br /></div><div>It remains to be seen how much of the <span class="Apple-style-span" style="font-weight: bold;"><span class="Apple-style-span" style="font-style: italic;">computation</span></span> in the brain is attributable to the astrocytes. And also what 'neural network' models might really <span class="Apple-style-span" style="font-style: italic;">mean</span> ;)</div><div><br /></div><div class="blogger-post-footer"><p>_Moss<img src="http://mohinish.s.googlepages.com/mossicon.png" alt="moss" width="16" height="16" /><img src="http://mohinish.s.googlepages.com/feed-icon-16x16.png" alt="feed" width="16" height="16" />Feed_</p></div>mohinishhttp://www.blogger.com/profile/07121978396381676854noreply@blogger.com1tag:blogger.com,1999:blog-26945663.post-80470091681090477332008-06-14T18:08:00.004+02:002008-06-14T18:21:31.661+02:00Geek tee<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjMM3jwTg5V7M83spxs9t7PaAezvEa3CB-ic_hPvyE1J-mz_QduIhdkYJZEqzoBNeFy_LvABFGMCr7g58gRTDzcPdfisMAhXM9R_imhTnbGlTItCgVn2MODLToV30-T4xdNxv03Ew/s1600-h/mathero.png"><img style="float:left; margin:0 10px 10px 0;cursor:pointer; cursor:hand;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjMM3jwTg5V7M83spxs9t7PaAezvEa3CB-ic_hPvyE1J-mz_QduIhdkYJZEqzoBNeFy_LvABFGMCr7g58gRTDzcPdfisMAhXM9R_imhTnbGlTItCgVn2MODLToV30-T4xdNxv03Ew/s400/mathero.png" border="0" alt="" id="BLOGGER_PHOTO_ID_5211772184770905858" /></a><div> Intended for a very specific clientele, the <a href="http://www.cafepress.com/shop4mo">Matlab Hero T-Shirt</a>. </div><div class="blogger-post-footer"><p>_Moss<img src="http://mohinish.s.googlepages.com/mossicon.png" alt="moss" width="16" height="16" /><img src="http://mohinish.s.googlepages.com/feed-icon-16x16.png" alt="feed" width="16" height="16" />Feed_</p></div>mohinishhttp://www.blogger.com/profile/07121978396381676854noreply@blogger.com1tag:blogger.com,1999:blog-26945663.post-90853894166901730252008-05-08T15:56:00.003+02:002008-06-14T18:56:34.775+02:00I use features<span class="Apple-style-span" style="font-style: italic;">What I tried to say</span>:<div>"Greek place"</div><div>
</div><div><span class="Apple-style-span" style="font-style: italic;">What I ended up saying</span>:</div><div>"Breek ... errr..."</div><div>
</div><div><span class="Apple-style-span" style="font-style: italic;">What this means</span>:</div><div>The initial consonant of word 2 lent it's [place] feature to the initial consonant of word 1; BUT, word 1 kept it's [voicing] feature intact. Thus, /g/ -> /b/</div><div>
</div><div>Looks like I do use something like a feature after all :) </div><div>Moral: pay close attention to your slips of the tongue and other speech errors...</div><div>
</div><div>-----------</div><div>UPDATE</div><div>-----------</div><div>
</div><div>Chris K swaps features between the onset and the coda of a single syllable - </div><div>"wis.<span class="Apple-style-span" style="font-weight: bold;">dom</span>" -> "wis.<span class="Apple-style-span" style="font-weight: bold;">bon</span>"</div><div>by swapping the onset [+alveolar] with the coda [+bilabial]; leaving the rest intact...</div><div>
</div><div>Medal and honors to her.</div><div>
</div><div class="blogger-post-footer"><p>_Moss<img src="http://mohinish.s.googlepages.com/mossicon.png" alt="moss" width="16" height="16" /><img src="http://mohinish.s.googlepages.com/feed-icon-16x16.png" alt="feed" width="16" height="16" />Feed_</p></div>mohinishhttp://www.blogger.com/profile/07121978396381676854noreply@blogger.com0tag:blogger.com,1999:blog-26945663.post-12018732757437812342008-05-04T22:33:00.012+02:002008-05-05T14:21:50.229+02:00The Mystery of SixteenWhat's with Sixteen and <a href="http://www.facebook.com/"><span class="blsp-spelling-error" id="SPELLING_ERROR_0">Facebook</span></a>?<br /><br /><span style="font-style: italic;">Background 1</span>: <span class="blsp-spelling-error" id="SPELLING_ERROR_1">Facebook</span> recently released an app called <a href="http://www.facebook.com/lexicon/">Lexicon</a>, that counts the occurrence of <span class="blsp-spelling-error" id="SPELLING_ERROR_2">upto</span> five words on <span class="blsp-spelling-error" id="SPELLING_ERROR_3">Facebook</span> wall posts and shows their relative usage over a period of several days.<br /><br /><span style="font-style: italic;">Background 2</span>: I happened to have done my <span class="blsp-spelling-error" id="SPELLING_ERROR_4">Ph</span>.D. with the awesome <a href="http://www.sissa.it/cns/lcd/jacques.htm">Jacques <span class="blsp-spelling-error" id="SPELLING_ERROR_5">Mehler</span></a>, who, along with one of his (other ;) star students <a href="http://www.unicog.org/main/pages.php?page=Stanislas_Dehaene">Stan <span class="blsp-spelling-error" id="SPELLING_ERROR_6">Dehaene</span></a>, wrote a paper way back in 1992, entitled 'Cross-linguistic regularities in the frequency of number words' (<span style="font-style: italic;">Cognition</span>, <span style="font-weight: bold;">43</span>, 1-29). In this paper, they found that in cross-linguistic comparison of written corpora, (a) the frequency of usage of a number was inversely proportional to its magnitude, and (b) there were some local increases in frequency, e.g. for 'hundred' or the multiples of 10 and some numbers between 10 and 20.<br /><br /><span style="font-style: italic;">Materials and methods</span>: Naturally, it behove me to look at how <span class="blsp-spelling-error" id="SPELLING_ERROR_7">Facebook</span> users went with this trend. You who know my method, would immediately guess that <span class="blsp-spelling-error" id="SPELLING_ERROR_8">Matlab</span> was made use of. It was, images were captured, axes drawn and relative frequencies (Lexicon does not give absolute frequencies... in fact, there is no y-scale) estimated.<br /><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhbT5KJitwho5AAG_jLuLzZ7fVljPKgf-tSQK6FXOEMMAS0U6q4uIAid6Wg96JdvymnNSruMG8Df4Tx8GvZ5HjoYnkPPf49sXvYMwTCfOKJBzksaSYaL43yJIEfLqTflO3WESNPeg/s1600-h/one2four.jpg"><img style="margin: 0pt 10px 10px 0pt; float: left; cursor: pointer;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhbT5KJitwho5AAG_jLuLzZ7fVljPKgf-tSQK6FXOEMMAS0U6q4uIAid6Wg96JdvymnNSruMG8Df4Tx8GvZ5HjoYnkPPf49sXvYMwTCfOKJBzksaSYaL43yJIEfLqTflO3WESNPeg/s400/one2four.jpg" alt="" id="BLOGGER_PHOTO_ID_5196633473301866738" border="0" /></a><br />Here is one image output from <span class="blsp-spelling-error" id="SPELLING_ERROR_9">Facebook</span>. The estimated relative frequencies are plotted in a log-log scale in the inset graph.<br /><br />As had been observed, there is a nice decrease in frequency going from 'one' to 'four'.<br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhiLm0RfsiK9lo00syoRjhkYjhDTa49wMyWCO5jAP0pCDLqmSps8Fhw8ww9HKpVpBnzzZ21G676n9APSyydk9YmgfvA2bCI6740NeakdVtweBhkQfAMNfOo9UsF5FeSUe1gZ1lfVg/s1600-h/ten2nineteen.jpg"><img style="margin: 0pt 10px 10px 0pt; float: left; cursor: pointer;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhiLm0RfsiK9lo00syoRjhkYjhDTa49wMyWCO5jAP0pCDLqmSps8Fhw8ww9HKpVpBnzzZ21G676n9APSyydk9YmgfvA2bCI6740NeakdVtweBhkQfAMNfOo9UsF5FeSUe1gZ1lfVg/s400/ten2nineteen.jpg" alt="" id="BLOGGER_PHOTO_ID_5196633477596834050" border="0" /></a><br />So far so good. But could lexicon actually also pick up the subtle local increases that Stan & Jacques found?<br /><br />So, I looked at the numbers between 11 and 18. Figure 2 (Numbers 10 to 19) shows the relation between the previous findings and the current ones. In the graph from the paper, each line is a different language (corpus). Ignoring the dotted lines, if you see the trends for the languages (usefully highlighted by me) and compare it with the inset from <span class="blsp-spelling-error" id="SPELLING_ERROR_10">Facebook</span> (in blue at the top), you see two things: (a) overall, the shapes are remarkably similar, BUT (b) 'sixteen' is vastly over-represented. <span class="blsp-spelling-error" id="SPELLING_ERROR_11">Hmm</span>.<br /><br />Bit of a puzzle, that. Has American English changed? Is it the difference in corpora? Theirs was the famous Francis and <span class="blsp-spelling-error" id="SPELLING_ERROR_12">Kucera</span> (1982), this was <span class="blsp-spelling-error" id="SPELLING_ERROR_13">Facebook</span>. Or is it because of the online, web nature of the <span class="blsp-spelling-error" id="SPELLING_ERROR_14">Facebook</span> 'corpus'?<br /><br />Well, that could be checked quickly enough. A bunch of <span class="blsp-spelling-error" id="SPELLING_ERROR_15">google</span> searches for 'eleven' through 'eighteen' produced (approximate) counts for these words on the web at large. I normalized the <span class="blsp-spelling-error" id="SPELLING_ERROR_16">Facebook</span> and the Google values by subtracting the minimum, adding 1 and dividing the whole by the maximum. The results are shown in the last figure. For the most part, there's a pretty amazing concordance between <span class="blsp-spelling-error" id="SPELLING_ERROR_17">Facebook</span> and Google. Except for 'sixteen'!<br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg7Ns9E9CqZ-8ttjaJv09cuqEhzCuuRKh34cl6lJibd87R23YcccXiRLktZALaczBEXOiyg90FYjsgfmA_C-MVm7prhz-LnfBJVL7LiZuejRua5gZvPdT7SCnA6Xd78GijXShBj0g/s1600-h/facevsggl.jpg"><img style="margin: 0pt 10px 10px 0pt; float: left; cursor: pointer;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg7Ns9E9CqZ-8ttjaJv09cuqEhzCuuRKh34cl6lJibd87R23YcccXiRLktZALaczBEXOiyg90FYjsgfmA_C-MVm7prhz-LnfBJVL7LiZuejRua5gZvPdT7SCnA6Xd78GijXShBj0g/s400/facevsggl.jpg" alt="" id="BLOGGER_PHOTO_ID_5196639275802683682" border="0" /></a><br /><br /><br /><br />Well, I must admit, I am rather puzzled. What's with sixteen? <span class="blsp-spelling-error" id="SPELLING_ERROR_18">Ok</span>, so it's the age for getting a driver's license in most states, but so what? And why is <span class="blsp-spelling-error" id="SPELLING_ERROR_19">Facebook</span> different from the rest of the web? Is there something sinister?<br /><br /><br /><br /><span style="font-size:130%;"><span style="font-weight: bold;">UPDATE:<br /><br /></span><span style="font-size:100%;">So, I did some more poking around. One hypothesis (suggested by Celeste) was that this had to do with the American cultural association of 16 with 'coming of age' plus the fact that <span class="blsp-spelling-error" id="SPELLING_ERROR_20">Facebook</span> is primarily a teenage phenomenon. I thought, instead, that this might have to do with the fact that <span class="blsp-spelling-error" id="SPELLING_ERROR_21">Facebook</span> is a social networking site. To test this, I looked at some stats off of <a href="http://www.myspace.com/"><span class="blsp-spelling-error" id="SPELLING_ERROR_22">myspace</span></a>, using <span class="blsp-spelling-error" id="SPELLING_ERROR_23">Google's</span> handy site-specific searching, e.g. 'sixteen site:<span class="blsp-spelling-error" id="SPELLING_ERROR_24">myspace</span>.com'. The results are shown in the next figure:<br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiStumfcAL3T-jXZOlvPg5rr2LqGTjWGuMdSFedYBzQe8EUVorS3mejAV0i1HncLfKWqNv5YyCGf0j-YVBx-1x-rWmsKYO-pHzQbjlA2mUSBPqO4_17MhrK8kohUU5dVE91MTS9ww/s1600-h/ggmyfc.jpg"><img style="margin: 0pt 10px 10px 0pt; float: left; cursor: pointer;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiStumfcAL3T-jXZOlvPg5rr2LqGTjWGuMdSFedYBzQe8EUVorS3mejAV0i1HncLfKWqNv5YyCGf0j-YVBx-1x-rWmsKYO-pHzQbjlA2mUSBPqO4_17MhrK8kohUU5dVE91MTS9ww/s400/ggmyfc.jpg" alt="" id="BLOGGER_PHOTO_ID_5196864396513503538" border="0" /></a><br /><br /><br />These data show that <span class="blsp-spelling-error" id="SPELLING_ERROR_25">myspace</span>, like <span class="blsp-spelling-error" id="SPELLING_ERROR_26">Facebook</span>, has a spike in the count of 'sixteen'; something not found in the original study or in the stats from the whole web (<span style="font-style: italic;"><span class="blsp-spelling-error" id="SPELLING_ERROR_27">google</span></span> in the graph).<br /><br />So, this supports the idea that social networking sites have an unexplained spike in 'sixteen'.<br /><br />To look a little more into this, I looked at the phrase 'sweet sixteen'. Now Lexicon allows you to specify phrases as well as individual words. So I did that. As controls, I had 'thirteen', which we know is pretty low (and not just in American, although the exact reasons for the cross-culturally low values are not clear but are discussed in the original paper). And, I added in 'turned sixteen' and 'sixteen years' as other relevant phrases. The results from Lexicon in the next picture are clear: 'Sweet sixteen' shows up VERY frequently, while the other phrases don't even show up!<br /><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjphJKEaUPv1VzOiDjRTLbMOIgThCYpx84HH-aqLr4Cd9E9cfz5ZZEe4dEryIGIcB37SgKOKhnQriPqF67iW5NW5NLWbmLFQj3-AWlUiLwiJPqCJA5ZMDFfqmWOSPvmilbf93FwCw/s1600-h/sweet16.jpg"><img style="margin: 0pt 10px 10px 0pt; float: left; cursor: pointer;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjphJKEaUPv1VzOiDjRTLbMOIgThCYpx84HH-aqLr4Cd9E9cfz5ZZEe4dEryIGIcB37SgKOKhnQriPqF67iW5NW5NLWbmLFQj3-AWlUiLwiJPqCJA5ZMDFfqmWOSPvmilbf93FwCw/s400/sweet16.jpg" alt="" id="BLOGGER_PHOTO_ID_5196866612716628322" border="0" /></a><br />Once again, I used <span class="blsp-spelling-error" id="SPELLING_ERROR_28">Matlab</span> to estimate the frequency of the phrase 'sweet sixteen'- it accounts for nearly a THIRD of all occurrences. In the final graph, I plot the occurrences of 'sixteen' on <span class="blsp-spelling-error" id="SPELLING_ERROR_29">Facebook</span> either with (blue) or without the phrase 'sweet sixteen' (red, dotted).<br /><br />Now suddenly the picture looks much more like the original and like Google!<br /><br />So, the REAL question is, what's with social networking sites (<span class="blsp-spelling-error" id="SPELLING_ERROR_30">ok</span>, I haven't done this with <span class="blsp-spelling-error" id="SPELLING_ERROR_31">Myspace</span> yet) and 'sweet sixteen'???<br /><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEghzjrKTO995D7UKjocU2tW_B6eKAU7SozFB-1GVHAN1P0kHo1aR6Xp22MS5urZSbblcUaYPriDoqc5Xp_HZk3394Ns5XKuWSnxE2qEQg7l7QpwUT3ueCzl3mCHBuC2mZk6IA2TTQ/s1600-h/fbsweet16.jpg"><img style="margin: 0pt 10px 10px 0pt; float: left; cursor: pointer;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEghzjrKTO995D7UKjocU2tW_B6eKAU7SozFB-1GVHAN1P0kHo1aR6Xp22MS5urZSbblcUaYPriDoqc5Xp_HZk3394Ns5XKuWSnxE2qEQg7l7QpwUT3ueCzl3mCHBuC2mZk6IA2TTQ/s400/fbsweet16.jpg" alt="" id="BLOGGER_PHOTO_ID_5196866617011595634" border="0" /></a></span></span><div class="blogger-post-footer"><p>_Moss<img src="http://mohinish.s.googlepages.com/mossicon.png" alt="moss" width="16" height="16" /><img src="http://mohinish.s.googlepages.com/feed-icon-16x16.png" alt="feed" width="16" height="16" />Feed_</p></div>mohinishhttp://www.blogger.com/profile/07121978396381676854noreply@blogger.com4tag:blogger.com,1999:blog-26945663.post-77219679685437512192008-04-06T19:02:00.009+02:002008-04-06T22:48:24.922+02:00Statistical inferenceImagine that a statistical reasoner was trying to build an appropriate model of when I go to the gym. What would such a model entail? In a very general sense, it would be some kind of prediction about the (say hourly) probability that I go to the gym.
So, given some data, for each of the 24 hours in a day the model would make some prediction about how likely I am to go to the gym. Observing the data (so far), it might make certain generalizations. (1) The probability of going to the gym is zero at 00(hrs), is some value >0 between 0800 and 1900, and then drops down to zero after 1900.
Further, if the model had access to my (woefully inadequate) Google calendar, it would know that the probability that I went to the gym during the hours that my Google cal said I was supposed to be at a meeting was close to zero.
Add more observable, contextual variables. The probability that I go to the gym rises in the hours following my eating a protein bar. It is also higher when my car is parked at the campus. The availability of a fresh change of clothes increases the probability , while my drinking a coke drives it lower.
Eventually, I'm quite certain that these factors taken together would come up with a model of my gym-going behavior with a pretty good level of accuracy. You could consult this model and know, at any given hour, how likely it is that I am actually <span style="font-style: italic;">at</span> the gym, and you won't be terribly wrong.
However! if you thought that the model was a <span style="font-style: italic;">causal</span> model, you would have got the whole causal structure inverted: as far as I'm concerned, I go to the gym <span style="font-style: italic;">when it darn well pleases me</span>. Of course I cannot go when I'm fast asleep, and I do tend to sleep mostly between 1900 and 0800 the next day. Of course I'd rather sit in meetings than go <span class="blsp-spelling-error" id="SPELLING_ERROR_0">gymming</span>. But these are not the <span style="font-style: italic;">reasons</span> I go to the gym; these are the <span style="font-style: italic;">restrictions</span> that permit or disallow my going to the gym.
This is just like the Buddhist idea of <span style="font-style: italic;">substantial causes</span> and <span style="font-style: italic;">cooperative conditions</span>. The first is the actual cause; the second are factors that make the effect possible. In my reading, the failure of <a href="http://en.wikipedia.org/wiki/Behaviorism">Behaviorism</a> is in identifying the cooperative conditions as substantial causes.
I think that this also the pitfall that's right next to every statistical learning view of acquisition in cognition. As Chomsky, Pinker and others have belabored, the point is that you need to posit <span style="font-style: italic;">mental causes</span> for observed behaviors. Observed behaviors in themselves don't constitute a causal theory.
However, what the causal theory itself should look like is a tough problem. The reason is that we can postulate as many or as few mental variables, but we won't necessarily know which is the right set. It seems that some sort of <a href="http://en.wikipedia.org/wiki/Occam%27s_Razor">Occam's razor</a> over introspectively (intuitively) hypothesized causal models would be the best bet. It's in this light that I'm viewing the research of <a href="http://web.mit.edu/cocosci/josh.html">Josh <span class="blsp-spelling-error" id="SPELLING_ERROR_1">Tenenbaum</span></a>, for example. And here's where the <a href="http://en.wikipedia.org/wiki/Bayes%27_theorem">Bayesian</a> approach might be most useful- I think of it as the best implementation (so far) of Occam's razor.<div class="blogger-post-footer"><p>_Moss<img src="http://mohinish.s.googlepages.com/mossicon.png" alt="moss" width="16" height="16" /><img src="http://mohinish.s.googlepages.com/feed-icon-16x16.png" alt="feed" width="16" height="16" />Feed_</p></div>mohinishhttp://www.blogger.com/profile/07121978396381676854noreply@blogger.com0