tag:blogger.com,1999:blog-250323842024-03-14T05:35:50.710-05:00The Mentaculuspsychology, statistics, & trade-offsAndy McKenziehttp://www.blogger.com/profile/07314450642021911177noreply@blogger.comBlogger613125tag:blogger.com,1999:blog-25032384.post-69769821311294430262013-06-30T17:01:00.000-05:002013-06-30T17:01:02.209-05:00Feed Changes<div dir="ltr" style="text-align: left;" trbidi="on">
1) In case you find yourself in an acute panic looking for a last-minute alternative for GR, I am now using <a href="http://www.feedly.com/">Feedly</a> as my RSS reader. I haven't used it enough to recommend it one way or another, but import at least is easy.<br />
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2) In an effort to consolidate various interests, I am now blogging exclusively <a href="http://andrewtmckenzie.com/news/">here</a>. If you're interested in keeping up with me, please follow that link and/or paste it (http://andrewtmckenzie.com/news/) into your RSS reader of choice. Even if you don't want to subscribe to the new blog, thanks for reading. </div>
Andy McKenziehttp://www.blogger.com/profile/07314450642021911177noreply@blogger.comtag:blogger.com,1999:blog-25032384.post-59931901555145974172012-09-12T17:02:00.000-05:002012-09-12T17:03:03.049-05:00The Embryology Of Spin<div dir="ltr" style="text-align: left;" trbidi="on">
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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj9HBr5eIU5_nFnuNaEUGWwtyxIIlKQOeBht9MU-fZxBJgMuQSaXp32Rjr4KC6qO48f9GxUV1-ewCknIwKGAcNMIlejwa_lS1GLMpaKRY7U6GnbC9z46D7PJCON5WNneYOUGxWv/s1600/Screen+shot+2012-09-12+at+5.37.52+PM.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="242" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj9HBr5eIU5_nFnuNaEUGWwtyxIIlKQOeBht9MU-fZxBJgMuQSaXp32Rjr4KC6qO48f9GxUV1-ewCknIwKGAcNMIlejwa_lS1GLMpaKRY7U6GnbC9z46D7PJCON5WNneYOUGxWv/s320/Screen+shot+2012-09-12+at+5.37.52+PM.png" width="320" /></a></div>
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Yavchitz et al. <a href="http://www.plosmedicine.org/article/info:doi/10.1371/journal.pmed.1001308">looked at</a> which factors correlated with the presence of "spin" in the reporting of medical randomized control trials. Spin is emphasizing the benefits of a treatment more than is appropriate on the basis of the data. They cooked up a multivariate regression with the explanatory variables of journal type, funding source, sample size, type of treatment (drug or other), results of the primary outcomes (all nonstatistically significant versus other), author of the press release, and the presence of “spin” in the abstract conclusion.<br />
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In their sample (N = 41), the <i>only</i> factor that correlated significantly with spin in the press release and news article was spin. Spin in the abstract conclusions of a study leads to a 5.6 (95% CI 2.8–11.1) times higher relative risk of there being spin in the press release and news reports. So, to the extent that we care about curbing vicious information cascades, it's essential for authors and editors to be conscientiousness about word choice and framing in the abstract. </div>
Andy McKenziehttp://www.blogger.com/profile/07314450642021911177noreply@blogger.comtag:blogger.com,1999:blog-25032384.post-31856869078848815262012-09-04T18:14:00.000-05:002012-09-04T18:14:48.079-05:00The Trade-Offs Of Publicizing Your Goals<div dir="ltr" style="text-align: left;" trbidi="on">
In Ben Casnocha's <a href="http://casnocha.com/behind-the-book-lessons-publishing-business-book">reflections</a> on writing his book <a href="http://www.amazon.com/The-Start-up-You-Transform-ebook/dp/B0050DIWHU">The Start-Up Of You</a>, he mentions this tidbit:<br />
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When you embark on a project that’s going to take awhile, you have to decide how much to publicize the fact – on your blog, to your friends — that you’ve started. ... When you publicly announce that you’re starting toward a goal, you can benefit from the self-fulfilling prophecy effect, you can collect feedback from your network, and be held accountable to lots of external people tracking your progress. On the flip side, when you announce a goal, you risk tricking your mind into believing you’ve already partially accomplished your it when in fact you’ve done nothing. Derek Sivers says: “Keep your goals to yourself.”) Plus, external accountability of the wrong kind can add unhealthy pressure.</blockquote>
This is a complicated and thus interesting trade-off. It involves an interaction between managing your own psychology and providing others the context they need to offer you help. The best-case scenario (not necessarily possible) would be for others to know what you are attempting to do without you knowing that they know. On the other hand, the worst-case scenario (much more plausible) is that you think others know when they don't.<br />
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In science, there are often norms against sharing too much of your project with outsiders, to prevent it from being "<a href="http://en.wikipedia.org/wiki/Scoop_(term)">scooped</a>". It strikes me now that these norms serve the dual purpose of preventing you from taking mental credit for something that you haven't yet done the grunt work to accomplish.<br />
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Anyway, I certainly don't have any general solutions to this trade-off, and it is something I worry about too.<br />
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I am probably slightly biased about the book because Ben is a friend, but I <a href="http://www.amazon.com/review/RQ72FNTCQRUKG/ref=cm_cr_pr_perm?ie=UTF8&ASIN=B0050DIWHU">recommend it highly</a>.</div>
Andy McKenziehttp://www.blogger.com/profile/07314450642021911177noreply@blogger.comtag:blogger.com,1999:blog-25032384.post-22369665138260344102012-08-30T22:28:00.000-05:002012-08-30T22:28:32.047-05:00In Praise Of The Obvious, Pt 2<div dir="ltr" style="text-align: left;" trbidi="on">
Scott Aaronson <a href="http://www.scottaaronson.com/blog/?p=1121">explains</a> the usefulness of the <a href="http://en.wikipedia.org/wiki/Church%E2%80%93Turing_thesis">Church-Turing thesis</a> in a way that makes intuitive sense to me, a newbie to <a href="http://en.wikipedia.org/wiki/Theoretical_computer_science">TCS</a>. Awesome! That kind of post is why I love subscribing to his blog. The commenter Keith apparently disagrees, <a href="http://www.scottaaronson.com/blog/?p=1121#comment-52216">saying</a>,<br />
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It occurs to me that if you’re taking positions in arguments that I, a layman, could easily take, then you’re either wasting your time or indulging a hobby.</blockquote>
His attitude exemplifies why it's so important to <a href="http://andymckenzie.blogspot.com/2011/02/in-praise-of-obvious.html">relentlessly praise</a> those who understand the minutia in a field yet take the time and status hit to point out the obvious. If the pressure to complicate is manifest in an academic's blog posts, just imagine what one would feel while writing an illustrious journal article. </div>
Andy McKenziehttp://www.blogger.com/profile/07314450642021911177noreply@blogger.comtag:blogger.com,1999:blog-25032384.post-24198121721982612912012-07-24T18:08:00.000-05:002012-07-24T18:13:20.274-05:00Book Review: Great Flicks By Dean Simonton<div dir="ltr" style="text-align: left;" trbidi="on">
<i>Attention conservation notice</i>: Review and notes from a book discussing an academic topic that will likely only interest you insofar as it generalizes to other topics, unless you are both a huge stats and film nerd.<br />
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I'm fascinated by movie ratings and what they tell us about: 1) the best ways to use rigorous methods to study the quality of a subjective output, 2) how variable people's assessment of quality are, and 3) how people conceptualize their own opinion in the context of everyone else's. Dean Simonton is a giant in the psychology of creativity, and <a href="http://andymckenzie.blogspot.com/2010/09/three-surprising-findings-on-genius.html">I loved his book</a> <i>Creativity in Science</i>. So, as soon as I saw this one, I clicked "buy it now" on <a href="http://www.amazon.com/Great-Flicks-Scientific-Creativity-Aesthetics/dp/0199752036">its Amazon page</a>. </div>
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My typical gripe against academic investigations of movie ratings is that they discount imdb.com, a huge resource with millions of data points, segregated by age, gender, geographical location, on an incredibly rich array of movies. So, soon after buying the book, I searched in the Kindle app for "imdb" and found very few results. This predisposed me to disliking it. </div>
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A few of my other gripes: </div>
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1) It takes awhile to get used to Simonton's academic writing style. </div>
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2) The book takes few risks stylistically. Each chapter feels like it could be its own separate article. Thus, he does not take full advantage of the long-form medium. </div>
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3) When he discussed a few of the measures (such as the correlation between different award shows), I felt that there was some issues with his account of the causality. Surely there is some, non-negligible probability that people take the ratings of others' into account when they make their own judgments. He mentions this sometimes, but not enough for me, and ideally he'd come up with some creative way to try to get around it.</div>
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4) Finally, there are a few typos. I actually like seeing typos, because it makes me think that I am learning from a more niche source that others are less likely to appreciate, but YMMV.</div>
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By midway through the book, Simonton had won me back to a large extent. His analyses of his data were very well-done and he supplies tables so you can look at the regression coefficients yourself. And there are many good nuggets, such as: </div>
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- the best predictors of higher ratings are awards for better stories (e.g., best screenplay and best director), as opposed to visual or musical awards</div>
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- having individuals on the production team who play multiple roles (such as writer, cinematographer, and editor all at once) makes the film more successful, presumably due to creative freedom </div>
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- some amount of repeated collaboration over multiple films with the same individuals, but not too much, is optimal for winning awards (i.e., there is a trade-off between stimulation and stagnation) </div>
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- higher box office returns are inversely correlated with success at awards shows</div>
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<b>- the typical film is unprofitable; "about 80% of Hollywood's entire profit can be credited to just a little over 6% of the movies" </b></div>
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- the curse of the superstar: "if a star is paid the expected increase in revenue associated with his or her performance in a movie then the movie will almost always lose money" (this is because revenue is so positively skewed) </div>
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- divides movies into two types: those that are extremely successful commercially, and those that are extremely successful artistically (people often use the former to subsidize the latter) </div>
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<b>- negative critic reviews have a more detrimental impact than positive reviews have a boosting effect on box office returns</b></div>
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- on ratings, critics and consumers have similar tastes, although consumers' tastes are more difficult to predict, presumably because their proclivities are more diverse</div>
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<b>- for a consumer, the most important factor for whether they will watch a movie is its genre (#2 is word of mouth) </b></div>
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- dramas do worse in the box office, better at the awards shows; comedies are the reverse</div>
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- PG-13 movies make the most money; some romance, but no actual nudity, is best (and lots of action but no gore) </div>
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- on average, sequels do far worse in ratings and awards than the original movies</div>
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- the greater the involvement of the author in an adapted movie, the less money it will make (they interfere more and might care more about "artistic integrity" than making money) </div>
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- directors tend to peak in their late 30s; they have more success in their late 20s than their late 50s, on average</div>
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<b>- divides directors into two types: conceptual (innovative and imaginative; think Welles) and experimental (technical and exacting; think Hitchcock)</b></div>
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- conceptual directors express ideas through visual imagery and emotions, often leave behind one defining film, and decline quickly</div>
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<b>- experimental directors emphasize more realistic themes, slowly improve their methods, and their best films often occur towards (but almost never *at*) the end of their careers</b></div>
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- female actors make less money than their male counterpoints, and the best picture award correlates much better with best male actor than best female actor</div>
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- awards for scores are much better predictors of a film's quality than awards for songs</div>
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All in all, this book is far from perfect, but it is likely the best full-length treatment of quantitative movie ratings available. If you are interested in the topic, and occasionally find yourself doing things like browsing the rating histograms on imdb, then this is essential reading. </div>
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</div>Andy McKenziehttp://www.blogger.com/profile/07314450642021911177noreply@blogger.comtag:blogger.com,1999:blog-25032384.post-73755846536339247802012-07-20T20:22:00.000-05:002012-07-20T20:22:11.444-05:00Statistics Is Like Medicine, Not Software<div dir="ltr" style="text-align: left;" trbidi="on">
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Stats questions--even when they're pure cut-and-dried homework--require dialog. Medicine might be a better analogy than software: what competent doctor will prescribe a remedy immediately after hearing the patient's complaint? One of our problems is that the [Stack Exchange] mechanism is not ideally suited to the preliminary dialog that needs to go on.</blockquote>
That's from the ever erudite William Huber, in <a href="http://chat.stackexchange.com/rooms/4135/how-can-we-best-help-to-improve-the-questions-asked-on-our-site">this chat</a> about why the <a href="http://stats.stackexchange.com/">statistics Q&A site</a> has problems that the <a href="http://stackoverflow.com/">software Q&A site</a> does not. Some users argue that a high proportion of questions on the stats site should <i>not</i> be answered unless they are disambiguated further.<br />
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You might assume that "more answers are better," but answering an ill-posed question adds more noise to the internet. When searching to clarify an ambiguous term, somebody might find that question, read the answer, and end up even more confused. Recall that this is a field already stricken by <a href="http://andymckenzie.blogspot.com/2012/07/the-meaning-of-mean.html">diametric ideology and short-term incentives</a>.<br />
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<span style="background-color: white;">Here is my previous post on the </span><a href="http://andymckenzie.blogspot.com/2011/04/wisdom-of-whuber.html" style="background-color: white;">wisdom of Huber</a><span style="background-color: white;">. </span></div>Andy McKenziehttp://www.blogger.com/profile/07314450642021911177noreply@blogger.comtag:blogger.com,1999:blog-25032384.post-83357329666619331932012-07-08T21:23:00.001-05:002012-07-08T21:24:02.754-05:00The Psychosocial Costs Of Ambition<div dir="ltr" style="text-align: left;" trbidi="on">
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If I had accepted that leadership role, there would have been a lot of pressure on me to <i>do something really exciting</i>. I can sometimes do exciting things, but I can't do them on demand. My energy level waxes and wanes. My creativity is irregular. When I do have an idea, sometimes it catches on and other times people just stare at me and think "What's <i>wrong</i> with him?"<span style="background-color: white;"> </span></blockquote>
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To be ambitious is a commitment. It's saying "Take a chance on me, and I will continue being creative and exciting and dependable for the foreseeable future." It's promising people that you're never going to let them down. If you <i>act</i> ambitious, and then when push comes to shove you say "Nah, I don't need the aggravation", then you don't look ambitious and high-status, you look like a flake.</blockquote>
Scott's <a href="http://squid314.livejournal.com/316763.html">lucid explanation</a> of the costs to ambition is a great example of <a href="http://en.wikipedia.org/wiki/Empathy_gap">hot and cold decision-making</a>. We tend to overestimate the stability of our beliefs, so when we feel ambitious and full of energy (like, at the start of a project) we assume that this feeling will continue indefinitely.<br />
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Of course, this is unlikely. Most of us have daily circadian rhythms, some <a href="http://millar.bio.ed.ac.uk/andrewM/Jo%20Selwood%20site/other_rhythms.htm">less-well understood</a> medium-term fluctuations, and gradual decays in interest.<br />
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So, as Scott learned early in life, it is prudent to anticipate and explicitly correct for your likely decline in motivation towards a topic when you present yourself to the world. The insidious part of this is that if you want to obtain resources you need to actually complete a task (e.g., a job, a grant, collaborators), you will have to sell yourself. This is why trade-offs aren't fun; they're just real.</div>Andy McKenziehttp://www.blogger.com/profile/07314450642021911177noreply@blogger.comtag:blogger.com,1999:blog-25032384.post-37784474926637523162012-07-06T22:30:00.001-05:002012-07-06T22:30:48.806-05:00Is *Any* Human Activity Long-Run Sustainable?<div dir="ltr" style="text-align: left;" trbidi="on">
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Intensive rice agriculture began in the Yangtze basin about 8,000 years BP, a sustainable model for agriculture by any reasonable standard. The extensive water infrastructure network around Chengdu, China, has diverted part of the Min River through the Dujiangyan for both flood control and irrigation without restricting fish connectivity since 256 BC, while some forests in India have been actively managed by surrounding communities for even longer periods.</blockquote>
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That's from a <a href="http://www.plosbiology.org/article/info%3Adoi%2F10.1371%2Fjournal.pbio.1001344">guardedly optimistic article</a> by Matthews and Boltz. It's academic but contains most of the good aspects of scholarly writing (copious references, measured tone), without most of the others (argument to authority, unwillingness to point out the obvious). There are 2650 words so you should expect to read it in about 12 minutes. Assuming you are an average blog reader (well, above average if you're reading this one), I recommend it, unless you haven't stared at the <a href="http://en.wikipedia.org/wiki/File:Vostok_Petit_data.svg">Vostok ice core data</a> recently, in which case you should do that for 15 seconds first. </div>
</div>Andy McKenziehttp://www.blogger.com/profile/07314450642021911177noreply@blogger.comtag:blogger.com,1999:blog-25032384.post-30923254039784934742012-07-04T17:21:00.000-05:002012-07-04T17:25:11.976-05:00The Meaning Of The Mean<div dir="ltr" style="text-align: left;" trbidi="on">
Bob Carpenter has a <a href="http://draft.blogger.com/"><span id="goog_2094768136"></span>few enlightening thoughts<span id="goog_2094768137"></span></a> on the distinctions between 1) the sample mean, 2) the expected value of a random variable, and 3) the mean of a distribution. I've long been confused by the difference between the mean and expected value, and his trichotomy helps alleviate my confusion. With that in mind, I changed the intro of the article <a href="http://en.wikipedia.org/wiki/Mean">mean</a>, which had remained static since the dawn of time (2001, when the page was created).<br />
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Of the major subjects on Wikipedia, statistics seems to be the most convoluted. My two explanations for this are that 1) there are so many schools that disagree on fundamental interpretations (likelihood, non-parametric, empirical Bayesian, objective Bayesian, etc), and 2) many practitioners are so busy with applications that they don't have time to reconcile their disagreements.</div>Andy McKenziehttp://www.blogger.com/profile/07314450642021911177noreply@blogger.comtag:blogger.com,1999:blog-25032384.post-80364891007365734742012-06-20T00:59:00.000-05:002012-07-04T15:08:38.665-05:00When You Should Be Most Skeptical<div dir="ltr" style="text-align: left;" trbidi="on">
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One of the hardest things we can do as readers is disagree with the methods of authors we agree with ideologically. It makes us feel good to find authors who agree with us, but this is when we should be at our most skeptical. Searching the world for self-justification is not a worthwhile goal, it simply turns you into another short-sighted, argumentative know-it-all.</blockquote>
That's from Keely's scathing, analytical <a href="http://www.goodreads.com/review/show/1454411">review</a> of The Giver. I like the idea that we should be especially skeptical of the arguments of those we agree with, to counteract out <a href="http://en.wikipedia.org/wiki/Confirmation_bias">natural tendency</a> to the contrary.</div>Andy McKenziehttp://www.blogger.com/profile/07314450642021911177noreply@blogger.comtag:blogger.com,1999:blog-25032384.post-38082903860996597622012-06-13T20:19:00.002-05:002012-06-13T20:19:17.163-05:00When More Data Trumps Logic<div dir="ltr" style="text-align: left;" trbidi="on">
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A difficulty with the “more data is better” point of view is that it’s not clear how to determine what the tradeoffs are in practice: is the slope of the curve very shallow (more data helps more than better algorithms), or very steep (better algorithms help more than more data). To put it another way, it’s not obvious whether to focus on acquiring more data, or on improving your algorithms. Perhaps the correct moral to draw is that this is a <i>key</i> tradeoff to think about when deciding how to allocate effort. At least in the case of the AskMSR system, taking the more data idea seriously enabled the team to very quickly build a system that was competitive with other systems which had taken much longer to develop.</blockquote>
That's Michael Nielsen in an <a href="http://www.michaelnielsen.org/ddi/how-to-answer-a-question-a-simple-system/">interesting post</a> describing how machine learning question-and-answer systems work. I completely agree that identifying trade-offs is one of the most useful ways to decide how to proceed on a problem. That's why I think the <i>general study of trade-offs</i>, across fields, is underrated. </div>Andy McKenziehttp://www.blogger.com/profile/07314450642021911177noreply@blogger.comtag:blogger.com,1999:blog-25032384.post-91969104505243001302012-05-28T21:59:00.000-05:002012-05-28T21:59:00.373-05:00GATCACA<div dir="ltr" style="text-align: left;" trbidi="on">
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In many American states it is legal to screen and select on the basis of sex, for non-medical reasons. In fact, a 2006 study (see below) found that 9% of [preimplanation genetic diagnosis] procedures carried out in [in-vitro fertilization] clinics in the U.S. were performed for this reason. Other reasons include screening for an embryo with the same immune type (“HLA type”) as a current child who is ill and requires a transplant of some sort. Screening for these “savior siblings” was done in 1% of PGD procedures. And 3% used it for a reason I personally find jarring – to specifically select embryos with a mutation causing a genetic condition. This is usually in cases where both parents have either deafness or dwarfism and they want their child to be similarly affected. This gets into the political movement objecting to society labelling conditions as “disabilities”. I can sympathise with that to some degree – more for some conditions than others – but I think, if it were my child, I would still rather he or she could hear.</blockquote>
That's Kevin Mitchell, <a href="http://wiringthebrain.blogspot.com/2012/05/gattaca-and-coming-future-of-genetic.html">discussing</a> GATTACA, an entertaining sci-fi movie with a respectable 7.8 <a href="http://www.imdb.com/title/tt0119177/ratings">imdb rating</a>. Spoiler alert, the premise of the movie is that at some point in the future there will be strong stratification of people into two classes, the "valids" and the "invalids", based on whether they had healthy traits selected for via preimplanation genetic diagnosis.<br />
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It seems to me highly unlikely (<0.01%) that a nightmare scenario of this sort would actually occur. One of the main reasons is because of the large plurality of values among parents, as seen above. A prevailing reason people have kids is to propagate a form of themselves into the future, and in many ways it defeats the purpose when you select against certain traits or even perform some sort of genetic engineering.<br />
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The other reason is something we know now better than we did 15 years ago, when GATTACA was released. And that is that DNA doesn't actually explain all that much of physiology and behavior--there are also <a href="http://brainslab.wordpress.com/2011/02/26/synapse-communication-with-the-epigenome/">strong epigenetic effects</a> as well as <a href="http://wiringthebrain.blogspot.com/2009/06/nature-nurture-and-noise.html">stochastic effects of gene expression</a>. </div>Andy McKenziehttp://www.blogger.com/profile/07314450642021911177noreply@blogger.comtag:blogger.com,1999:blog-25032384.post-13290813790255949622012-05-27T19:14:00.000-05:002012-05-27T19:14:00.195-05:00No Darkness But Ignorance<div dir="ltr" style="text-align: left;" trbidi="on">
Here's Nancy Kanwisher's <a href="http://www.danielbor.com/dilemma-weak-neuroimaging/#comment-77">suggestion</a> on how to improve the field of neuroimaging:<br />
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NIH sets up a web lottery, for real money, in which neuroscientists place bets on the replicability of any published neuroimaging paper. NIH further assembles a consortium of respected neuroimagers to attempt to replicate either a random subset of published studies, or perhaps any studies that a lot of people are betting on. Importantly, the purchased bets are made public immediately (the amount and number of bets, not the name of the bettors), so you get to see the whole neuroimaging community’s collective bet on which results are replicable and which are not. Now of course most studies will never be subjected to the NIH replication test. But because they MIGHT be, the votes of the community are real.... </blockquote>
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First and foremost, it would serve as a deterrent against publishing nonreplicable crap: If your colleagues may vote publicly against the replicability of your results, you might think twice before you publish them. Second, because the bets are public, you can get an immediate read of the opinion of the field on whether a given paper will replicate or not.</blockquote>
This is very similar to Robin Hanson's <a href="http://hanson.gmu.edu/gamble.html">suggestion</a>, and since I assume she came up with the idea independently, it bodes well for its success. Both Hanson and Kanwisher are motivated to promote an honest consensus on scientific questions.<br />
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When <a href="http://en.wikipedia.org/wiki/John_P._A._Ioannidis">John Ioannidis</a> came to give a talk at the NIH (which was interesting), I <a href="http://videocast.nih.gov/Summary.asp?File=17176">asked him</a> (skip to 101:30) for his thoughts on this idea. He laughed and said that he has proposed something similar.<br />
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Could this actually happen? Over the next ten years, I'd guess almost certainly not in this precise form; first, gambling is illegal in the US, and second, the markets seem unlikely to scale all that well.<br />
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However, the randomized replication portion of the idea seems doable in the near term. This is actually <a href="http://openscienceframework.org/project/shvrbV8uSkHewsfD4/wiki/index">now being done for psychology</a>, which is a laudable effort. It seems to me that randomized replications are likely precursors to any prediction markets, so this is what interested parties should be pushing now.<br />
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One objection is that these systems might encourage scientists to undertake more iterative research, as opposed to game-changing research. I have two responses. First, given the current incentives in science (i.e., the primacy of sexy publications), this might actually be a useful countervailing force.<br />
<br />
Second, it seems possible (and useful) to set up long-standing prediction markets for a field, such as, "will the FDA approve an anti-amyloid antibody drug to treat Alzheimer's disease in the next ten years?". This would allow scientists to point to the impact that their work had on major questions, quantified by (log) changes in the time series of that market after a publication. </div>Andy McKenziehttp://www.blogger.com/profile/07314450642021911177noreply@blogger.comtag:blogger.com,1999:blog-25032384.post-72009431680594020282012-05-26T18:08:00.001-05:002012-05-26T18:15:39.258-05:00Evaluating The Regret Heuristic, Part II<div dir="ltr" style="text-align: left;" trbidi="on">
<div>
In a comment to my post on <a href="http://andymckenzie.blogspot.com/2010/11/our-regrets-change-over-time.html">how our regrets change over time</a>, <a href="http://schwitzsplinters.blogspot.com/">Eric Schwitzgebel</a> asks, </div>
<blockquote class="tr_bq">
But why adopt regret minimization as a goal at all? Regret seems distorted by hindsight bias, status quo bias, and sunk cost bias, at least.</blockquote>
<div>
I've <a href="http://andymckenzie.blogspot.com/2009/03/evaluating-regret-heuristic.html">written before</a> that projecting your future views about your present actions can be a good way to make decisions. So, Eric's prompting is a good occasion to re-evaluate that.</div>
<div>
<br /></div>
<div>
Given perfect information, the theoretically best way to make decisions is to 1) calculate the costs and benefits of each possible outcome, 2) estimate how your choice affects the relative probability of those outcomes, 3) use the costs and benefits as inputs to some sort of valuation function, and 4) make the decision with the highest probabilistic value. </div>
<div>
<br /></div>
<div>
<a href="http://en.wikipedia.org/wiki/Cost%E2%80%93benefit_analysis">Cost-benefit analysis</a> is a common way to implement this, with, say, <a href="http://en.wikipedia.org/wiki/Quality-adjusted_life_year">QALYs</a> as the value measure. If you have perfect information, this is just math. </div>
<div>
<br /></div>
<div>
But as Ben Casnocha <a href="http://casnocha.com/2008/11/regret-aversion.html">says</a>, if you don't have enough information, that framework can break down. In particular, even when #2 is pretty straightforward, #1 can still be very tricky. For example, although studying for the LSAT makes it much more likely that I will earn a JD, it's still hard to quantify the precise costs and benefits of entering that earning that degree. </div>
<div>
<br /></div>
<div>
Here is where the regret heuristic can be useful. Instead of explicitly tallying each cost and benefit, it asks: in total, which would you regret more: studying or not studying? </div>
<div>
<br /></div>
<div>
This is in fact a simplifying measure, but there remains oodles of freedom in how you perform the regret estimation. For example, you can:</div>
<div>
<ul style="text-align: left;">
<li>use as <a href="http://en.wikipedia.org/wiki/Reference_class_forecasting">reference classes</a> your current regrets about your previous, similar actions and/or the regrets of other people who have made similar decisions, or just make it up; </li>
<li>integrate your regret over all of your possible future states (e.g., ages) <a href="http://andymckenzie.blogspot.com/2010/09/trade-off-9-some-now-vs-more-later.html">weighted by their probability of occurring</a>, or just choose one arbitrary time point; </li>
<li>extend the regret over <a href="http://andymckenzie.blogspot.com/2010/07/heyman-on-alcoholics-anonymous.html">broad classes of choices you could make</a>, or keep it local;</li>
<li>apply systematic techniques to adjust for various biases (e.g., <a href="http://en.wikipedia.org/wiki/Impact_bias">impact</a>, <a href="http://en.wikipedia.org/wiki/Confirmation_bias">confirmation</a>, <a href="http://en.wikipedia.org/wiki/Status_quo_bias">status quo</a>, <a href="http://en.wikipedia.org/wiki/Hindsight_bias">hindsight</a>, <a href="http://en.wikipedia.org/wiki/Planning_fallacy">planning</a>, <a href="http://en.wikipedia.org/wiki/Loss_aversion">sunk cost</a>), or not.</li>
</ul>
</div>
<div>
Ultimately, I still think that the regret heuristic can be a useful one. But tread carefully, as there are many crucial micro-decisions to make; it's not magic. </div>
</div>Andy McKenziehttp://www.blogger.com/profile/07314450642021911177noreply@blogger.comtag:blogger.com,1999:blog-25032384.post-36392055460586457562012-05-25T01:12:00.001-05:002012-05-25T01:17:48.840-05:00Age's Stealing Steps<div dir="ltr" style="text-align: left;" trbidi="on">
Michael Wolff has written a gripping but narrative-heavy <a href="http://nymag.com/print/?/news/features/parent-health-care-2012-5/">article</a> about the troubles he has experienced in addressing his mother's worsening dementia. It is hard not to feel for him and his family. Still, I think there are two perspectives which his piece underemphasized:<br />
<br />
1) Many debilitated but cognitively intact individuals do have a good quality of life. For example, in a <a href="http://www.ncbi.nlm.nih.gov/pubmed/22288767">recent survey</a> of 62 seniors with an average of 2.4 <a href="http://en.wikipedia.org/wiki/Activities_of_daily_living">daily living</a> dependencies and fairly good cognitive well-being (≥ 17/30 on the <a href="http://en.wikipedia.org/wiki/Mini%E2%80%93mental_state_examination">MMSE</a>), 87% reported that they had a quality of life somewhere in the fair to very good range. I consider this to be a testimony to the resiliency of the human psyche. Also, it makes me worry that people will read the article and think that <a href="http://en.wikipedia.org/wiki/Long-term_care_insurance">LTC insurance</a> is only useful for those with dementia, which Wolff implies, when that is far from the case.<br />
<br />
2) Why is it that many of the doctors depicted his story seem so unhelpful? There's little doubt that fear of litigation plays a role. For example, in a <a href="http://www.ncbi.nlm.nih.gov/pubmed/22401355/">Mar '12 study</a>, over half of the 600+ palliative care physicians surveyed reported being accused of euthanasia or murder within the past five years. In many respects this is a legislative issue, and I wish his article had discussed that angle more.<br />
<br />
Many pointers in this post go to the excellent blog <a href="http://www.geripal.org/">GeriPal</a>. </div>Andy McKenziehttp://www.blogger.com/profile/07314450642021911177noreply@blogger.comtag:blogger.com,1999:blog-25032384.post-62584234690827596332012-05-24T02:10:00.000-05:002012-05-24T02:10:34.088-05:00Should Revenge Have Bounds?<div dir="ltr" style="text-align: left;" trbidi="on">
I recently finished Steven Pinker's <a href="http://www.amazon.com/The-Better-Angels-Our-Nature/dp/0670022950">book</a> attempting to explain the decline of human-on-human violence over the last twenty thousand years. All in all, I recommend it. It has noteworthy psychology nuggets on nearly every page, explained with good data and lucid metaphors. I especially enjoyed how he built up many cute explanations of various phenomena--like the Freakonomics-popularized abortion theory of the crime rate decrease in the 1990s--only to soundly and evenly debunk them. My two major points of disagreement:<br />
<br />
1) As Tyler Cowen <a href="http://marginalrevolution.com/marginalrevolution/2011/10/steven-pinker-on-violence.html">argues</a>, it is possible that although the mean number of causalities from interstate conflicts has been falling, the variance has been increasing. Aside from WWII, we can't easily observe this variance, though we can see signs of it in events like the <a href="http://en.wikipedia.org/wiki/Cuban_Missile_Crisis">Cuban Missile Crisis</a>. Pinker employs per-capita log-scales for many of his charts and on these WWII does not seem quite as bad, but still it sticks out indelibly.<br />
<br />
Wisely, Pinker does not project the decrease in violence indefinitely into the future, rather seeking to explain what we have observed so far, so his thesis is technically immune to this critique. Still, I imagine that there have been some not-easily observed <a href="http://en.wikipedia.org/wiki/Stanislav_Petrov">historical aberrations</a> which, if they had gone differently, would have meant that this book would never had been written. The <a href="http://en.wikipedia.org/wiki/Winner's_curse#Related_uses">winner's curse</a> comes to mind.<br />
<br />
2) As one reads about the incredible violence that occurs in US prisons, it is difficult not to wonder whether the benefits to decreasing violence always outweigh the costs. I have previously written about the <a href="http://andymckenzie.blogspot.com/2010/10/trade-off-12-protection-vs-freedom.html">protection vs freedom trade-off</a>. The laudable decrease in person-to-person violence comes at the cost of constraining the actions of individuals by probabilistically putting them in prison. This is an <a href="http://www.theatlantic.com/national/archive/2012/05/yes-america-we-have-executed-an-innocent-man/257106/">imperfect process</a> and has negative externalities in that it further exacerbates the burden of those locked up for non-violent crimes.<br />
<br />
So, I would have liked to see more discussion about the violence in modern-day prisons and whether it is more apt to say that violence has been displaced rather than decreased. In a provocative article, Christopher Glazek <a href="http://nplusonemag.com/raise-the-crime-rate">argues</a> that the US should be more like the UK and have slightly looser violent crime convictions which would make the conditions in prison slightly less awful. In most cases I would probably come down in favor of protecting innocent bystanders, but it is a conversation that needs to happen and that I wish Pinker had addressed. </div>Andy McKenziehttp://www.blogger.com/profile/07314450642021911177noreply@blogger.comtag:blogger.com,1999:blog-25032384.post-61626624099421957512012-04-29T11:01:00.000-05:002012-04-29T11:01:28.907-05:00A Brief History Of Bioinformatics, 1996-2011<div dir="ltr" style="text-align: left;" trbidi="on">
<div class="separator" style="clear: both; text-align: center;">
<a href="http://www.ploscompbiol.org/article/info%3Adoi%2F10.1371%2Fjournal.pcbi.1002487" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="274" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi50bppCMJzpzCuz7XPn4VQKeKFeLmj1OEQQQ5PBT2ZNNUxSgMT6UkY3hBvNIQC_ZdXXlUAi6s12nCfL1N0c37tmJMqKoreJPKPmjW-V3309YyBe_pg9-40XbzJXlvEFU8IwUrA/s320/Screen+shot+2012-04-29+at+11.57.16+AM.png" width="320" /></a></div>
<br />
That's from an <a href="http://www.ploscompbiol.org/article/info%3Adoi%2F10.1371%2Fjournal.pcbi.1002487">interesting article</a> by Christos Ouzounis. Here he discusses the "adolescence" period:<br />
<blockquote class="tr_bq">
One factor in policymakers' high expectations might have been a certain lack of milestones: due to the field's dual nature, that of science and engineering, computational biology rarely has the “eureka” moment of a scientist's discovery and is grounded in the laborious yet inspired process of an engineer's invention. </blockquote>
And there's this bit, too:<br />
<blockquote class="tr_bq">
The notion of computing in biology, virtually a religious argument just 10 years ago, is now enthroned as the pillar of new biology.</blockquote>
So why has "bioinformatics" become less discussed? In part, because it has been so successful. </div>Andy McKenziehttp://www.blogger.com/profile/07314450642021911177noreply@blogger.comtag:blogger.com,1999:blog-25032384.post-77630537570056660622012-04-13T23:52:00.001-05:002012-04-13T23:52:57.294-05:00Schelling Points And Bioinformatics<div dir="ltr" style="text-align: left;" trbidi="on">
A lot of what think about when I do bioinformatics is how to set parameters non-arbitrarily. Basically I am looking for <a href="http://en.wikipedia.org/wiki/Focal_point_(game_theory)">Schelling points</a>: round, clear numbers that are easy to justify. The classic case is setting a p-value threshold to 0.05, which has been around for <a href="http://www.jerrydallal.com/LHSP/p05.htm">over eighty years</a> and is still going strong, <a href="http://xkcd.com/882/">despite the haters</a>. Other examples are setting <a href="http://www.ncbi.nlm.nih.gov/BLAST/tutorial/Altschul-1.html">e-value</a> thresholds to 0.01 and setting <a href="http://en.wikipedia.org/wiki/Bayes_factor">Bayes factor</a> thresholds of 10 as the first to indicate "strong" evidence. Like <a href="http://andymckenzie.blogspot.com/2010/08/spectrums-everywhere.html">any threshold</a>, these are arbitrary, but following the <a href="http://en.wikipedia.org/wiki/Foundations_of_statistics#Other_reading">paradigm of statistics as rhetoric</a>, their staying power make sense insofar as scientists need to be able to resort to standard procedures to settle debates. Anyway, I have no profound point here, I just think it's cool that a seemingly esoteric topic affects what I actually do on a day-to-day basis.<br />
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<div class="separator" style="clear: both; text-align: center;">
<a href="http://www.flickr.com/photos/70391825@N00/5349762634/" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="319" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjEgsolsieifuzsw82Tp5rFapvvYwD8krlHiTL3JgOAEhf94M2m9N4sHCLTXe7xZrZD7lFyJ4EtCI4VRh-PEXr6yhMX_2VCATGWRU6dfwDEtIkyG5BHyiHBGHucl4AJP3ARmLeX/s320/Screen+shot+2012-04-14+at+12.48.17+AM.png" width="320" /></a></div>
<br /></div>Andy McKenziehttp://www.blogger.com/profile/07314450642021911177noreply@blogger.comtag:blogger.com,1999:blog-25032384.post-7295809445095580992012-04-13T22:08:00.001-05:002012-04-13T22:08:59.044-05:00Is It Possible, In Principle, To Do Methodologically Sound Research?<div dir="ltr" style="text-align: left;" trbidi="on">
In a paper published 31 years ago, Joseph McGrath argues (<a href="http://www.mendeley.com/research/dilemmatics-study-research-choices-dilemmas/">html</a>, <a href="http://www2.psych.ubc.ca/~schaller/528Readings/McGrath1981.pdf">pdf</a>) that the answer is no. Specifically, he claims that any research design faces two trade-offs: 1) being obtrusive vs unobstrusive (which maps to my terminology as <a href="http://andymckenzie.blogspot.com/2010/11/trade-off-15-acquiring-info-vs-altering.html">acquiring info vs altering subject</a>), and 2) being generalizable vs context-cognizant (which maps to my terminology as <a href="http://andymckenzie.blogspot.com/2010/10/trade-off-14-precision-vs-simplicity.html">precision vs simplicity</a>).<br />
<br />
In his terminology, these trade-offs allow for the optimization of three distinct values (generalizability of samples to populations; precision in measuring variables; and context realism for the participants). Initially, I disagreed with this. To me, intuition suggests that there should be four points which maximize certain qualities when you are considering the intersection of two-trade offs: one in each corner of the 2-d space.<br />
<br />
One way to get around this is if you claim that, in the context of this decision (study design), the trade-offs are not independent. For example, it might be very difficult for a design to be both highly generalizable and highly obstrusive.<br />
<br />
Below I've drawn an example. Think of the dots as realizations of actually feasible study designs sampled from someone's mental generation process; i.e., they are probably not at the absolute extremes of the theoretical distribution, but with enough realizations, would come close.<br />
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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhdBBhVj8cRTJh_kOKd7FP6NDDd8n5Mk0VAXbHNXdSOvDUH36DjqjN3hkgA0gmBNuUtDFoWhRm-CZckFYjK6Ymk2FrMpV7sR8a4636PLX7MacSuwNJPBeKpHAWRXk-jfaNgBUqZ/s1600/Screen+shot+2012-04-13+at+11.05.11+PM.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="261" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhdBBhVj8cRTJh_kOKd7FP6NDDd8n5Mk0VAXbHNXdSOvDUH36DjqjN3hkgA0gmBNuUtDFoWhRm-CZckFYjK6Ymk2FrMpV7sR8a4636PLX7MacSuwNJPBeKpHAWRXk-jfaNgBUqZ/s320/Screen+shot+2012-04-13+at+11.05.11+PM.png" width="320" /></a></div>
<br />
I'm not sure that I agree with this exact distribution, and it would need some justification, but it seems like the only way to justify his three-pronged rather than four-pronged set-up.</div>Andy McKenziehttp://www.blogger.com/profile/07314450642021911177noreply@blogger.comtag:blogger.com,1999:blog-25032384.post-16273416687247672262012-03-31T11:33:00.001-05:002012-03-31T11:33:40.805-05:00The Valiant Never Taste Death But Once<div dir="ltr" style="text-align: left;" trbidi="on">
After reading this <a href="http://www.salon.com/2012/03/18/the_evolution_of_death/singleton/">interesting excerpted article</a> from Dick Teresi's book <i>The Undead</i>, which discusses the difficulties in defining death by a single, consistent set of criteria and the social qualms that stirs, I decided to check out the <a href="http://www.amazon.com/The-Undead-Harvesting-Ice-Water-Cadavers--How/dp/0375423710/ref=sr_1_1?s=books&ie=UTF8&qid=1333207217&sr=1-1">Amazon reviews</a>. The associated ratings were (and still are) quite shockingly bad! They follow the classic <a href="http://andymckenzie.blogspot.com/2011/02/so-bad-its-good-on-imdb.html">"so bad it's good"</a> distribution, with 5 5-star ratings, 1 3-star rating, and 33 1-star ratings. So, given that I am always up for a good controversy, I decided to read and <a href="http://www.amazon.com/review/R88XOA8FXYWK9/ref=cm_cr_pr_perm?ie=UTF8&ASIN=B005IEGKNE&nodeID=&tag=&linkCode=">review it myself</a>. Ultimately I mostly side with the critics, giving it two stars. If you are interested in the subject matter, I'd suggest instead Kenneth Iserson's <a href="http://www.amazon.com/Death-Dust-What-Happens-Bodies/dp/1883620074">Death to Dust</a>, which is a bit older but much more level-headed and thorough treatment of similar issues. </div>Andy McKenziehttp://www.blogger.com/profile/07314450642021911177noreply@blogger.comtag:blogger.com,1999:blog-25032384.post-12605351849034525962012-03-30T21:46:00.000-05:002012-03-30T21:46:04.536-05:00What Makes Phrases Memorable<div dir="ltr" style="text-align: left;" trbidi="on">
For 1000 movies, <a href="http://arxiv.org/abs/1203.6360">this study</a> compared lines included on imdb's memorable quotes page to those that were not. People who hadn't seen the movies were able to pick the correct one 78% of the time, although,<i> caveat lector</i>, that's with only n = 68.<br />
<br />
What features allow this above chance classification? The authors suggest 1) distinctiveness (i.e., a lower likelihood of coming from <a href="http://en.wikipedia.org/wiki/Brown_Corpus">samples of standard English text</a>), 2) generality (fewer personal pronouns, more present tense), and 3) complexity (words with more syllables and fewer coordinating conjunctions like "for" and "and").<br />
<br />
Interestingly, their best support vector machine only correctly classified examples 64% of the time, so either the human data is somehow biased, or there are plenty more subtleties for machines to learn before they can best us humans in recognizing literary wit. </div>Andy McKenziehttp://www.blogger.com/profile/07314450642021911177noreply@blogger.comtag:blogger.com,1999:blog-25032384.post-34164555559734298042012-03-29T22:49:00.000-05:002012-03-29T23:13:44.588-05:00Indexing Wikipedia Article Submissions On Pubmed<div dir="ltr" style="text-align: left;" trbidi="on">
I have <a href="http://andymckenzie.blogspot.com/2011/08/power-to-wiki-people.html">complained before</a> about few academics writing Wikipedia pages and instead writing reviews that few people will read. So, I feel compelled to admit that <a href="http://www.ploscompbiol.org/article/info%3Adoi%2F10.1371%2Fjournal.pcbi.1002446">this</a> is really cool:<br />
<blockquote class="tr_bq">
We suggest a principal reason for this limited breadth and depth of coverage of topics in computational biology is one that affects a number of disciplines: reward. Authors in the biomedical sciences get academic reward for publishing papers in reputable journals that are indexed in PubMed and have associated digital object identifiers (DOIs).... </blockquote>
<blockquote class="tr_bq">
Topic Pages are the version of record of a page to be posted to (the English version of) Wikipedia. In other words, PLoS Computational Biology publishes a version that is static, includes author attributions, and is indexed in PubMed. In addition, we intend to make the reviews and reviewer identities of Topic Pages available to our readership. Our hope is that the Wikipedia pages subsequently become living documents that will be updated and enhanced by the Wikipedia community...</blockquote>
I continue to be impressed by the innovation from the PLoS suite. </div>Andy McKenziehttp://www.blogger.com/profile/07314450642021911177noreply@blogger.comtag:blogger.com,1999:blog-25032384.post-2053184319345367432012-03-26T20:28:00.000-05:002012-03-26T20:28:00.088-05:00Why Does Speed Variability Create Congestion?<div dir="ltr" style="text-align: left;" trbidi="on">
<div class="separator" style="clear: both; text-align: center;">
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<a href="http://www.ploscompbiol.org/article/slideshow.action?uri=info:doi/10.1371/journal.pcbi.1002442&imageURI=info:doi/10.1371/journal.pcbi.1002442.g008#" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="164" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEixbkgmbl8jYPk-K0aU1EIFG5ZrAzcEqxhmcH5EGNFodTgte_EuFsrd7QCevQpejQgMYq5XyN0dOC6MzYikSsA5Yk2uoNkXOcZYtavUKER9lywR-G6gS6GHKRINpLeXZFlFUL4d/s400/Screen+shot+2012-03-25+at+8.37.33+PM.png" width="400" /></a></div>
<br />
Above are the results from one trial of <a href="http://www.ploscompbiol.org/article/info%3Adoi%2F10.1371%2Fjournal.pcbi.1002442">an experiment</a> designed to answer this question. Participants were randomly assigned to one of two groups, each with its own walking direction and color.<br />
<br />
The authors defined "clusters" as groups of people walking in basically the same path, with some leeway. They then did simulations to determine the average lifetime of a cluster as a function of the group's variability in walking speed. As you can see, the greater the variability, the shorter the lifetime of the clusters.<br />
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<div class="separator" style="clear: both; text-align: center;">
</div>
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="http://www.ploscompbiol.org/article/info%3Adoi%2F10.1371%2Fjournal.pcbi.1002442" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="170" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgMSxJBa4nzHNosLEM7ILDAXIdYAuoMrrclA11J1fCrwXISDeiBw_IVP7p4Zz5fxmLmYnsg3SjPW1B2BTa9AC5JIfUZd7Qa_bPBt1ZEt_acrT8Tn75DN1DI_bkuphlPP3Bwux0K/s200/Screen+shot+2012-03-25+at+8.48.30+PM.png" width="200" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">N = the number of pedestrians in the simulation</td></tr>
</tbody></table>
This trend fits with their experimental results. Here's how the authors explain it:<br />
<blockquote class="tr_bq">
[T]hose moving faster catch up with those walking slower, leaving an empty zone in front of the slow walkers ... [P]edestrians who are willing to walk faster than others make use of density gaps to overtake the slow walkers in front of them. By doing so, faster pedestrians move away from their lane, and meet the opposite flow head-on a few seconds later. This initial perturbation often triggers a complex sequence of avoidance maneuvers that results in the observed global instabilities. </blockquote>
So here's a situation where more diversity, defined as inter-individual variability, leads to worse outcomes. Of course, as the authors mention, there are many other situations, such as collective decision making, where inter-individual variability is actually quite helpful.<br />
<br />
Perhaps more diversity generally serves the function of pushing a group out of local optima. So you can think of diversity as shifting a group more towards the "explore" side of the <a href="http://andymckenzie.blogspot.com/2011/03/trade-off-19-exploration-vs.html">exploration-exploitation trade-off</a>. This would hurt in situations with a clearly defined goal, such as pedestrians walking in a circle as quickly as possible. But it might help in more complex situations.</div>Andy McKenziehttp://www.blogger.com/profile/07314450642021911177noreply@blogger.comtag:blogger.com,1999:blog-25032384.post-56060676030584362062012-03-25T18:47:00.000-05:002012-03-25T18:47:36.022-05:00Comp Exams For Each Course<div dir="ltr" style="text-align: left;" trbidi="on">
<blockquote class="tr_bq">
The solution I propose is comprehensive exams at the end of each course, much like Advanced Placement exams, that thoroughly and objectively distinguish students on merit alone. The emphasis in each classroom would then shift from fighting the teacher for high grades to cooperating with the teacher to learn the material necessary to perform on the exam.</blockquote>
That's from Andrew Knight, in an essay discussing problems that will not be new to anyone who is or has recently been in school; more <a href="http://www.fairfaxtimes.com/article/20120323/OPINION/703239696/1065/an-open-letter-to-college-admissions-committees&template=fairfaxTimes">here</a>. This is exactly what I wanted during most of my science and math courses. The alternative is to place a greater emphasis on big standardized tests like the SAT, but there can be so much variability in results from just one day.<br />
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One question is whether such exams could be a part of classes that are less fact-based, such as history and english. There is actually a machine learning competition for automated essay grading going on <a href="http://www.kaggle.com/c/asap-aes/details/Evaluation">right now</a>. I don't pretend to know the answer to this question, but even if it is currently infeasible, that shouldn't stop the tests from being used in math, science, and foreign language classes. </div>Andy McKenziehttp://www.blogger.com/profile/07314450642021911177noreply@blogger.comtag:blogger.com,1999:blog-25032384.post-1946162774521594402012-02-25T23:32:00.002-05:002012-02-25T23:32:50.327-05:00Snub City At The Oscars<div dir="ltr" style="text-align: left;" trbidi="on">
Of the <a href="http://oscar.go.com/nominees#Best%20Picture">Best Picture nominees</a>, The Artist is currently the highest rated on imdb, at 8.4, though it will drop. A good comparison is Avatar, because both movies are technically adventurous, and they both have terrifyingly trite plots.<br />
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The main difference between Avatar and The Artist is that the latter is about the past, triggering nostalgia, whereas the former is about one possible version of the future, and is thus discomforting. This is why The Artist will win Best Picture and Avatar didn't come close. (No movie set in at any point in the future has ever won the award.)<br />
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But of course, the best movie of the past year is A Separation. The fact that it wasn't even nominated just showcases the Academy's striking anti-foreign film bias.<br />
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It is obviously very fun to hate on the Academy, and there are many good reasons to do so, but as imdb user Fish_Beauty <a href="http://www.imdb.com/title/tt1655442/board/flat/194800894?p=4">reminds us</a>, this year is highly unlikely to go down as the biggest black mark of all time. Here are the lowest rated Best Picture winners:<br />
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Around the World in Eighty Days (1956) 6.8/10 9,106 (which won over the amazing <a href="http://www.imdb.com/title/tt0049406/">The Killing</a>)<br />
The Greatest Show on Earth (1952) 6.7/10 5,177 (which won over <a href="http://www.imdb.com/title/tt0044706/">High Noon</a>)<br />
The Broadway Melody (1929) 6.4/10 2,459<br />
Cavalcade (1933) 6.3/10 1,421<br />
Cimarron (1931) 6.1/10 1,739 (which won over the best silent film ever, <a href="http://www.imdb.com/title/tt0021749/">City Lights</a>)<br />
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These are truly embarrassingly bad films.</div>Andy McKenziehttp://www.blogger.com/profile/07314450642021911177noreply@blogger.com