tag:blogger.com,1999:blog-47250061522909776012024-03-18T12:52:03.173-04:00Luis von BlogLuis von Ahnhttp://www.blogger.com/profile/03028143830490915261noreply@blogger.comBlogger48125tag:blogger.com,1999:blog-4725006152290977601.post-78844495526229301192010-07-26T09:38:00.004-04:002010-07-26T10:27:21.260-04:00Work and the InternetFor context about why I care, here is a slight paraphrasing from grant proposal I recently wrote:<br /><blockquote>For the last eight years, I have been working to develop an area of computer science called "human computation," which studies how to harness the combined power of humans and computers to solve problems that would be impossible for either to solve alone. This growing academic field now has an annual workshop, a community with researchers from the top computer science programs in the world, and has directly influenced the popular online trend of crowdsourcing, in which crowds of people are enticed to perform work over the Internet. Subsequent to the development of this area, for example, Amazon created Mechanical Turk, a marketplace for human computation tasks (or “human intelligence tasks” as they call them), which is now used and studied by hundreds of researchers worldwide. Since then, other similar services have emerged where workers are paid to perform micro-tasks that are hard for computers. </blockquote><br />An example of human computation is <a href="http://www.google.com/recaptcha">reCAPTCHA</a>, in which people <a href="http://www.google.com/recaptcha/learnmore">help digitize books</a> by typing CAPTCHAs on the Internet. To date, over 750 million unique people—more than 10% of humanity—have helped transcribe at least one word through reCAPTCHA. <br /><br />All human computation systems must have a way to motivate the users to participate. In the case of reCAPTCHA, the value proposition is as follows: by typing a CAPTCHA, the user gets access to a desired resource like a free email account or tickets to a concert, and in exchange they perform ten seconds of work that is utilized to help transcribe a book. In the case of Mechanical Turk, users are paid a few cents to perform each task. <br /><br />A discussion that I've had with multiple people over the last few years is whether systems like Mechanical Turk, in which real money is exchanged, should be legislated so that workers are fairly compensated. You see, the average hourly rate of most workers in such sites is usually well below the minimum wage of most third world countries. As a concrete example, the minimum wage in Guatemala is approximately $1/hour, whereas it's not rare to see tasks on Mechanical Turk in which the effective hourly rate is $0.30/hour. (It's amazing that many of the workers on Mechanical Turk come from inside the United States.) Some labor economists would tell you that this is ok: if people are willing to work for such low rates, who is to stop them? However, most countries have some notion of a minimum wage in their laws, including the United States, so in essence as a country we do not believe in an unregulated labor market. <br /><br />Recently I have heard more than one company saying something like: "We use Mechanical Turk because otherwise we would have to pay people $7/hour to do this task." In other words: "We use Mechanical Turk to get around the minimum wage laws." As wrong as it may sound to some, this is currently ok. In the United States, "independent contractors" are typically not covered by minimum wage laws, so while I'm not a lawyer I believe using Mechanical Turk to get around minimum wage is as legal as hiring independent contractors instead of full-time employees. <br /><br />But the question remains: Should sites like Mechanical Turk be regulated? Perhaps not today, but if the Internet or crowdsourcing really is the future of work, we should at least be thinking about it.<br /><br />Here are some issues that make this complicated:<br /><br /><li>Labor markets like Mechanical Turk are truly global, with workers coming from many different countries. Can the same minimum wage be applied to all?<br /><br /><li>Most countries have immigration work laws that prevent people without the proper visa to work inside that country. Should these still apply when the work is performed over the Internet? In many cases it's not even possible to tell where the worker is located, so are these laws even enforceable?<br /><br /><li>Assume we decide as a country that labor markets like Mechanical Turk should be legislated and a minimum wage is imposed. Some of the work on human computation involves transforming tasks into enjoyable games so that people perform them in exchange for entertainment. Is it ok to pay people less (or nothing) if the task is fun?<br /><br /><li>What about writing a review for a book online or rating a video? These are concrete pieces of work that benefit the Web sites, but that nobody seems to object to doing for free.Luis von Ahnhttp://www.blogger.com/profile/03028143830490915261noreply@blogger.com28tag:blogger.com,1999:blog-4725006152290977601.post-23317343167602218692010-06-19T11:01:00.001-04:002010-06-19T12:45:58.207-04:00Research versus TeachingMy previous post stirred some people's emotions. Reading the comments, it seems part of that came from the tension between teaching and research in modern American universities. <br /><br />In most countries, the role of universities is solely to educate their students. That's true of many colleges in the United States, but not of <a href="http://en.wikipedia.org/wiki/Research_I_university">Research I universities</a>. The majority of American universities you've heard of belong to this category: Harvard, Yale, UCLA, Stanford, MIT, CMU, Princeton, etc. In addition to teaching, these institutions have another equally important role, which is to produce high-quality research that benefits society. Indeed, many of the game-changing discoveries or inventions in the last century have been entirely or partly developed at American Research I universities: The Internet, Google, the cure for polio, vitamin D milk, even Gatorade. To a large extent, this is where Nobel prizes are won, and where the future is invented. <br /><br />American Research I universities are also mostly responsible for educating the smartest people in the country (or even the world), both at the graduate and undergraduate levels. This includes most doctors, lawyers, politicians, US presidents, dot com billionaires, and yes, even Lady GaGa.<br /><br />Combining these two very important roles may have benefits, but it also causes an unspoken tension. Is the job of a professor primarily to educate or to do research?<br /><br />The interesting thing is that everybody seems to have a different opinion about this. Students and their paying parents, of course, think professors are there solely to educate; Professors mostly think they are there to do research; and university administrators seem to change their tune depending on whom they’re talking to. <br /><br />As usual with me, I have more questions than answers. Should research and education be combined in this manner? Should professors primarily concentrate on research or teaching?<br /><br />Regardless of what <b>should</b> happen, I can tell you that at least from a tenure-track professor’s point of view, the system at the vast majority of Research I universities is extremely biased towards the research side. Most of my friends at other universities chose to be professors because they want to do research without being pressed by economic outcomes like they would in a company, and consider teaching a bearable chore that they must do to get the freedom and prestige of being a professor. The hiring of faculty (at least at the ~15 Research I universities that have offered me a job) pays almost no attention to the potential quality of the candidates as teachers. The tenure process also puts teaching in the back seat. So in essence, professors are largely not selected, evaluated, or rewarded based on teaching. <br /><br />This is not to say that there are no good teachers among the faculty at Research I universities. Many of the faculty both here at CMU and elsewhere are outstanding instructors and work very hard on their teaching. However, they do so out of pure love (and possibly a misconceived sense of duty), because the system is not set up for this. <br /><br /> Since I don’t want to get in trouble again with the commenters, I will end with a few disclaimers. First, I do spend a significant amount of time on my teaching (as evidenced by having won the teaching award). Second, there are very good institutions that educate smart people in the US that are not Research I universities and that concentrate solely on teaching.Luis von Ahnhttp://www.blogger.com/profile/03028143830490915261noreply@blogger.com29tag:blogger.com,1999:blog-4725006152290977601.post-69549527616754344732010-06-16T13:19:00.006-04:002010-06-16T19:50:26.120-04:00Outsourcing My Research GroupA PhD student at Carnegie Mellon costs approximately $80,000 per year. (Research programmers and post-docs cost about the same.) Given that PhD students have to take classes for the first couple of years and are therefore running at 50% capacity, this means that each effective person in my research group costs on average $100,000 per year. <br /><br />I'm from Guatemala. For $100,000, you can hire 4-5 extremely competent full-time engineers there (even accounting for the 50% overhead rate inside CMU). My question today is: would it make sense to take 5 engineers instead of a PhD student next time I have extra money?<br /><br />I understand that CMU PhD students have a much higher IQ than the average programmer, and that for certain tasks you can't just rely on programmers, but if the exchange rate is 5 to 1, I think the experiment is worth a try. <br /><br />And from there, it's a slippery slope: why not just move my whole research group to India or China, since a large fraction of our PhD students come from there anyways?<br /><br />Part of the goal of being a professor is mentoring, and I love that part: I am not saying we should get rid of PhD students, but that perhaps a mix of some outsourced coding and PhD students would be a better investment for everybody. <br /><br /><b>Disclaimer:</b> 100% of my PhD students are working on projects of their own choosing, and if anything my biggest flaw as an advisor is not giving them enough direction (instead of micromanaging them).Luis von Ahnhttp://www.blogger.com/profile/03028143830490915261noreply@blogger.com62tag:blogger.com,1999:blog-4725006152290977601.post-74145432722950988262010-06-09T23:57:00.000-04:002010-06-09T23:58:11.073-04:00America's Next Top NerdI want to make a computer science reality TV show. Like in most reality shows, the participants would compete to win a prize, but since they would be CS nerds, we won't aim for something as crazy as getting married to a famous person (maybe it can be something like becoming Facebook friends with a girl). <br /><br />Anyways, instead of athletic or beauty competitions, I want the participants to compete by solving computer science problems. My question is this: what are some good CS problems for TV? I have some thoughts, but I'd also like to hear what others have to say. Ideally the problems would: (1) explain a cool CS concept, (2) be accessible to a PBS-type audience (i.e., no PCP proofs), and (3) have something that can be filmed.Luis von Ahnhttp://www.blogger.com/profile/03028143830490915261noreply@blogger.com44tag:blogger.com,1999:blog-4725006152290977601.post-66277662028794561212010-06-07T00:01:00.003-04:002010-06-07T07:57:19.070-04:00Startups and CMU<i>Is Carnegie Mellon a good university to go to if you plan on working for or building a startup? </i>That's the question I was recently asked by somebody from the <a href="http://quora.com">Quora</a> team. I'm frequently asked similar questions because I started a company out of CMU that never moved out of Pittsburgh even after it was acquired by Google. Following another brief conversation about this on Twitter today, I decided it would be good to have an open discussion about startups and CMU. I'll start with my personal opinion, but hope that others pitch in. <br /><br />Personally, I think CMU is a great place to start a company. Granted, I'm biased because things worked out for me, but here are some objective reasons why I think more people should be starting technology companies out of CMU:<br /><br />1. <b>Talent Pool</b>. CMU graduate and undergraduate students are truly world class. The computer science PhD program is ranked #1 by USNews, and according to my recruiter friends, CMU is the #1 or #2 school by quantity of hires from companies with uber selective hiring standards such as Facebook or Google.<br /><br />2. <b>Less Competition for this Talent</b>. I won't claim that CMU students are strictly better than students from e.g. Stanford, but I will claim this: the competition for hiring a top student to join a startup at CMU is much much lower than at comparable schools in California or Boston, since it's not the case that everybody and their mother has a startup in Pittsburgh (last time I went to Silicon Valley, even the guy that served me at Starbucks, who overheard my conversation with a VC friend, started pitching me his company!). At CMU you'll have your pick of top talent to start a company with. <br /><br />3. <b>Opportunity for Different Ideas</b>. Don't get me wrong, I love Silicon Valley. But it always strikes me when I go there how much everybody thinks exactly the same as each other (most even dress the same as each other). While some herd mentality is ok, I think there is huge benefit to being outside of that bubble. <br /><br />If I were to start another company, I would do it out of CMU.Luis von Ahnhttp://www.blogger.com/profile/03028143830490915261noreply@blogger.com17tag:blogger.com,1999:blog-4725006152290977601.post-38526811042100054712010-05-24T20:47:00.003-04:002010-05-27T19:59:38.962-04:00Give Me Back My NameDear Person Who Took My Name on Twitter and Linked to a Porn Site,<br /><br />Yes, I know, I was stupid. I should have taken @LuisvonAhn years ago when I first signed up. But you have to understand, I didn't know Twitter would become such a big thing. I was just checking out reCAPTCHA on their registration page, and typed the first username that came to mind: @freakbit. (No comments, please.) Now, Twitter is big, I wanna start using it, and I am stuck with <a href="http://twitter.com/freakbit">@freakbit</a>. Would you consider giving the name back?<br /><br />Sincerely,<br />The real Luis von Ahn<br /><br />PS: Are you also the person who has the fake Luis von Ahn on Facebook? If so, please give that back as well! I won't accept your friend request.<br /><br /><b>Update:</b> People from both Twitter and Facebook were super helpful, so now I have @LuisvonAhn as my Twitter name, and there is no more FB impersonator :)Luis von Ahnhttp://www.blogger.com/profile/03028143830490915261noreply@blogger.com11tag:blogger.com,1999:blog-4725006152290977601.post-29844206537660549742010-03-25T22:27:00.003-04:002010-03-25T22:29:03.502-04:00Bored: Need Some Scandalous GossipMany people have emailed asking why I haven't posted on this blog for a while. Well, here's why: I've been busy working on a bunch of things including a super duper secret project. I have a big mouth, so I best not say anything else. <br /><br />I'm now taking a little break and I need some entertainment. I tried the TV but there was nothing good. Soooo... how about we try this: readers, use the handy anonymous comment box below to tell the world and me some gossip. Now, this gossip should be maximally entertaining to me, so here are the rules: (1) It should be juicy. (2) It should be related to computer science or technology in general. (3) Extra points if it has to do with CMU or any university. Let's see what you got.Luis von Ahnhttp://www.blogger.com/profile/03028143830490915261noreply@blogger.com34tag:blogger.com,1999:blog-4725006152290977601.post-51601936600148885442009-12-02T21:22:00.000-05:002009-12-02T21:22:57.750-05:00Advice On Grad School ApplicationsResearch statements, recommendation letters, GREs. 'Tis the season again for grad school applications. To save all the kiddies from embarrassment and rejection (which typically implies you'll just end up making more money at some tech company), I decided to write a list of DOs and DON'Ts to follow when writing your application. Perhaps the sage readers will have more advice in the comments.<br /><br />1. DON'T start your research statement with a quote from Albert Einstein. You may think that's a good idea, but so do the other 50% of the applicants. Hell, don't start it with any quote, unless it's from something like Gossip Girl. XOXO. <br /><br />2. DON'T say you've wanted to be a professor since you were 4 years old. We won't believe you. When you were 4, you either wanted to be a policeman, an astronaut, or a firefighter. Admit it. <br /><br />3. Computer Science is a field with many fads. Therefore, DON'T say you want to do research on genetic algorithms, or expert systems. Those are so 1980s. DO say you want to work on algorithmic game theory, cloud computing, or green computing. <br /><br />4. DON'T have your recommenders write that you are "from a good family." Unless that family has a Turing Award or two, we don't care. <br /><br />5. DON'T say you have a proof that P != NP and that you will only show it to us if we admit you. We may have admitted a guy like that once, but this mistake will not be repeated, so come up with your own gimmick.<br /><br />6. DON'T start your statement with "respected sirs." There are women in the faculty too, you know.<br /><br />7. DO mention the name of a professor that you want to work with, but make sure the professor is still alive.<br /><br />8. DON'T have a "recommender loop" in which you write a recommendation letter for somebody that is writing a recommendation letter for you. At least make the cycle of longer length to confuse us a bit. <br /><br />9. DO read over the version of the application that you submit to each school after doing a find-and-replace for the school name. Typos can creep up -- "I've always wanted to go to MIT, because the Barkeley faculty are the best."<br /><br /><br />XOXO.Luis von Ahnhttp://www.blogger.com/profile/03028143830490915261noreply@blogger.com20tag:blogger.com,1999:blog-4725006152290977601.post-37488784688590517712009-11-27T17:35:00.001-05:002009-11-27T17:54:39.559-05:00Serious Damage to HealthSo apparently this was run as an ad for Johnny Walker in Central America. I should ask them to pay me! (The other page had my name on it.) The best is what it says at the bottom: "Causes serious damage to health."<br /><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg-XI58UVl4z71hkQXSyOduq6f7tF-YAoEjLu5T1OOCzKSNbtxUz8JpCnECG9J1IxC_DWl7PmGPF8qxBykNyV9SgNxXe3qGS12uRnmxvSvDhOKUL3lUEFi1r3jIYnekBXAsY6urEAnmU0c/s1600/johnnywalker.jpg"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 304px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg-XI58UVl4z71hkQXSyOduq6f7tF-YAoEjLu5T1OOCzKSNbtxUz8JpCnECG9J1IxC_DWl7PmGPF8qxBykNyV9SgNxXe3qGS12uRnmxvSvDhOKUL3lUEFi1r3jIYnekBXAsY6urEAnmU0c/s400/johnnywalker.jpg" border="0" alt=""id="BLOGGER_PHOTO_ID_5408914060171578178" /></a>Luis von Ahnhttp://www.blogger.com/profile/03028143830490915261noreply@blogger.com9tag:blogger.com,1999:blog-4725006152290977601.post-43687452767479802892009-10-04T13:40:00.000-04:002009-10-04T13:41:04.438-04:00Choosing a New Department HeadOur computer science department is currently in the process of choosing a new department head. Since we're academics, no decision can be simple so the faculty has come up with a complex procedure that may involve a committee, campaigning, multiple rounds of voting, a dance-off, and a conclave. <br /><br />One of the steps is for every professor to write an essay saying what they think should be done to improve the department. Below is mine:<br /><br />Dear Colleagues,<br /><br />After careful analysis of the academic landscape, I am convinced the most important thing for Carnegie Mellon University is to build its social network. I believe our research, students and faculty are of the highest caliber, but I believe our social network lacks high-powered and famous individuals. Having such people associated with us will make our university more well-known and will grow our endowment. I propose a simple three-step plan to improve our connections:<br /><br />1. Spend one year's worth of operating budget to buy a house in the Hamptons, where rich and influential people have homes. <a href="http://www.sothebyshomes.com/hamptons/sales/0044449">This one would do</a>. <br /><br />2. Force Ryan O'Donnell, Anupam Gupta, and Luis von Ahn to spend their summers there. <br /><br />3. With their charm, these three professors would befriend all their high-powered neighbors and convince them that Carnegie Mellon is awesome.<br /><br />I hope the next department head has the vision and audacity to carry out this fool-proof plan.Luis von Ahnhttp://www.blogger.com/profile/03028143830490915261noreply@blogger.com14tag:blogger.com,1999:blog-4725006152290977601.post-59152006610724561902009-10-03T16:35:00.001-04:002009-10-03T18:08:09.556-04:00Email FAQs1. <i>Why has the frequency of your blog posts decreased?</i> <br />I'm currently too busy to come up with anything intelligent to say :(<br /><br />2. <i>Will you review this paper for me?</i> <br />See #1 above. I love you though.<br /><br />3. <i>Why are you so busy?</i><br />Yep... see #1.Luis von Ahnhttp://www.blogger.com/profile/03028143830490915261noreply@blogger.com9tag:blogger.com,1999:blog-4725006152290977601.post-74031922816045416072009-09-16T12:28:00.005-04:002009-09-16T12:38:44.644-04:00Just a LinkLinking to the <a href="http://googleblog.blogspot.com/2009/09/teaching-computers-to-read-google.html">Official Google Blog Post</a>. Google Acquires reCAPTCHA.Luis von Ahnhttp://www.blogger.com/profile/03028143830490915261noreply@blogger.com17tag:blogger.com,1999:blog-4725006152290977601.post-12448895584785143062009-07-19T15:29:00.000-04:002009-07-19T15:29:36.840-04:00Existential Questions and Utopian SalariesI know this is impossible, but wouldn’t it be great if everybody was paid a salary proportional to how much they actually helped humanity? In my book, then, stock traders or hedge fund analysts would get smaller salaries than they do now -- sorry to all of my friends who have chosen the financial world; while I think you’re great people and some of you have helped individuals make some money, I think we all agree that most of you are not helping humanity out in proportion to your multi-million dollar salaries. On the other hand, farmers should be making bank -- no farmers, no food; no food = bad. <br /><br />My question then is, if salaries worked this way, how much should scientists or professors be paid? More specifically, how much should computer science professors make? I became a professor in part because I wanted to help the world. But am I actually doing so? What does it mean to help the world? How do we measure this? Carnegie Mellon pays me a very healthy salary (although I wouldn’t mind a raise, boss), but I’d like to think that professors are underpaid compared to how much they would make in such a utopian system. It's not clear to me they are.Luis von Ahnhttp://www.blogger.com/profile/03028143830490915261noreply@blogger.com50tag:blogger.com,1999:blog-4725006152290977601.post-62287979792418007352009-07-12T08:10:00.002-04:002009-07-12T08:23:42.879-04:00Hollywood-Style LecturesTeaching is hard, and teaching well is REALLY hard. If you’ve never done it before, you have no idea how many hours of preparation each lecture takes. The trick to counter that is to teach the same class over and over. By the n-th time you teach it, you can get away with much less preparation, but even then some of the lectures truly suck. <br /><br />I teach the same class every other semester: Great Theoretical Ideas in Computer Science. If you’re a CMU undergrad, you surely have strong memories about this class (positive or negative). If you’re not, all you need to know is that it’s a discrete math course required for all computer science majors and usually has about 200 students in it. When I spend millions of hours preparing for the class, it ends up being pretty good (teaching awards, very high student evaluations, etc.) Unfortunately, some weeks I don’t have millions of hours to spend on it so the lectures are not as good as I would want them to be (and the students fall asleep!). But let’s all be honest here: even when I prepare a lot, the lectures are not all that great. I make mistakes, I forget to say some things, my handwriting is bad, my jokes fall flat, etc. Every semester there are maybe 3-4 lectures that I am happy with afterwards, and of the rest about 50% totally suck in my mind and 50% are just barely passable. The fact that I am considered one of the better teachers of the department is, truthfully, sad. <br /><br />So, a good fraction of my lectures totally suck. I am also quite tired of repeating almost the same thing over and over every semester (and what sucks more is that sometimes it comes out great and sometimes it doesn’t!). So here’s my proposal: instead of my amateurish attempts at making good lectures that fail most of the time, and instead of repeating the same crap every semester like a broken record, why don’t I just produce really good video lectures? <br /><br />Now, I know what you will say: “Video lectures suck! They tend to put the students to sleep even more than real life professors, the audio quality is poor, you can’t see the board, etc.” And I agree. There is just something about being there in real life that cannot be captured by a video and this makes recorded lectures be even crappier than their real life counterparts. <br /><br />But I’m not talking about simply recording myself giving a regular lecture. I think that would suck. I am talking about making a high production value movie for every lecture. I’m talking about professional script writers (those guys that make the Daily Show or the Colbert Report so funny), about special effects and computer graphics to illustrate the concepts instead of the board, about high end directors, cameramen, and producers (like the guys who made <a href="http://www.pbs.org/wgbh/nova/sciencenow/0401/04.html">my Nova special</a>). <br /><br />I’ve spoken with some of my friends in the movie industry (writers, producers and directors of Hollywood blockbusters), and they all seem quite excited about trying to do this. The biggest problem seems to be the cost. It’s hard to estimate how much each lecture would cost, and it clearly depends on how much quality you want, but it seems each lecture can be done for between $75k to $300k. If we make 30 lectures to cover the whole semester, that amounts to something between $2 million and $9 million. This type of investment is probably not worth it for higher-level classes that are only taken by a few people each semester. But for a discrete math class taken by 200 students every semester at CMU alone (and tens of thousands of students throughout the world every year), I think it’s well worth it. <br /><br />Thoughts?Luis von Ahnhttp://www.blogger.com/profile/03028143830490915261noreply@blogger.com45tag:blogger.com,1999:blog-4725006152290977601.post-72557920610341883882009-07-04T03:22:00.003-04:002009-07-05T15:32:18.350-04:00Laptop at the BeachWhy is it ok to read a book on the beach, but if you pull out your laptop everybody thinks you’re the biggest dork on earth? When I’m at the beach I just want to use my laptop (with its fancy display that works under the sun) to either surf the Web, do work, or watch TV on it. Please people, it’s 2009. Books are so last millennium. Those who know me know that I’m not the biggest fan of reading books -- I haven’t read one in about 5 years -- because they’re incredibly inefficient and to a large extent boring. I also dislike the pseudo-intellectual snobbery that sometimes comes with books: “the movie was ok but the book was much better” Really? Did the book also make $110 million in the box office? I don’t think so.<br /><br />What I need is the opposite of the kindle: a thing that looks like a book but that actually let’s me surf the Web and watch TV on it.Luis von Ahnhttp://www.blogger.com/profile/03028143830490915261noreply@blogger.com68tag:blogger.com,1999:blog-4725006152290977601.post-51119316019013584642009-06-09T07:48:00.000-04:002009-06-09T07:49:39.725-04:00Speaking at the Library of Congress<object width="425" height="344"><param name="movie" value="http://www.youtube.com/v/Aszl5avDtek&hl=en&fs=1&"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/Aszl5avDtek&hl=en&fs=1&" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="425" height="344"></embed></object>Luis von Ahnhttp://www.blogger.com/profile/03028143830490915261noreply@blogger.com23tag:blogger.com,1999:blog-4725006152290977601.post-24288853480240704332009-05-17T17:18:00.002-04:002009-05-17T17:20:21.736-04:00Question of the DayIf you had $100 million, how would you use it to improve a university? I'd like a solution with maximal impact.Luis von Ahnhttp://www.blogger.com/profile/03028143830490915261noreply@blogger.com60tag:blogger.com,1999:blog-4725006152290977601.post-90833122856432480242009-05-12T23:03:00.004-04:002009-05-12T23:42:24.027-04:00How the Intertubes Can Help Fix Corrupt Governments(Fine, it's been a month since I last posted -- sue me, I've been busy.)<br /><br />Ok, so the Guatemalan president is being <a href="http://www.timesonline.co.uk/tol/news/world/us_and_americas/article6275384.ece">accused</a> of ordering the assassination of a well respected businessman, his daughter, and even his lawyer. It's like in the movies: the lawyer was gunned down on Sunday and on Monday <a href="http://www.youtube.com/watch?v=qlM_Kga8HhI">this video</a> (in Spanish) appeared on YouTube, in which the now dead lawyer basically says "if you're seeing this, it's because I've been assassinated by the president of Guatemala." Gotta love the third world. <br /><br />But this whole thing got me thinking. Guatemala, like many other third world nations, has a severe corruption problem. Every single president I can remember has been accused of stealing, laundering money, trafficking drugs, genocide, murder, and even killing a catholic bishop with a cinder block. Maybe half or all of these accusation are false, but the fact remains that the population simply has little to no trust in their government. (By the way, as far as I can remember, 100% of the presidential candidates in the last 25 years have run on the promise of ending government corruption.) The problem with such deep-rooted corruption (or perception of corruption) is that even if a truly honest guy becomes president, they cannot change anything because: (a) no matter what, the public believes the president is corrupt, and/or (b) since the rest of the government is so corrupt, an honest president is threatened to death if they don't cooperate with the corruption.<br /><br />So here's my proposal for the next honest guy who gets elected (I'm assuming that *some* of these guys actually want to fix the country): stick a camera and a microphone in your head and transmit 100% of your life live on the internet. And I mean 100%, so that nobody can ever accuse you of wrongdoings. <br /><br />And, come to think of it, why can't the US president do this? I know some of you will tell me that the public is not ready or fit to see all the presidential decisions, but I don't buy that. Let's try the experiment on some small country like Guatemala :)Luis von Ahnhttp://www.blogger.com/profile/03028143830490915261noreply@blogger.com29tag:blogger.com,1999:blog-4725006152290977601.post-45249048277199165332009-04-09T14:36:00.002-04:002009-04-09T21:38:03.614-04:00One Expensive Flea MarketTo all those out there providing services for high usage websites or companies: please stop trying to rip us off. <br /><br />With all the insane haggling you have to go through when running website, you'd think you're in a flea market somewhere in the developing world. Here are some contrasting examples:<br /><br /><b>Buying a Domain Name from a Squatter:</b> <br />Luis: How much do you want?<br />Squatter: $50,000<br />Luis: How about $250?<br />Final Sale Price: $600<br /><br /><b>My Aunt's Kidnapping in Guatemala:</b><br />Kidnapper: We want X<br />Final Ransom: X/20<br /><br /><b>Buying DNS Service:</b><br />Unnamed Company's Initial Offer: $X/month<br />Final Offer: $(X/10)/month<br /><br /><b>My Mom Buying Fruit in a Town Market:</b><br />Seller: Bananas for $1<br />Mom: I'll give you 10 cents<br />Seller: That's INSANE!<br />:<br />Mom: How about 12 cents?<br />Seller: FINE <br /><br />I'm tempted to hire a fruit seller from a Guatemalan market to become my chief negotiator.Luis von Ahnhttp://www.blogger.com/profile/03028143830490915261noreply@blogger.com22tag:blogger.com,1999:blog-4725006152290977601.post-40638788013956618322009-04-04T18:59:00.001-04:002009-04-04T19:02:42.265-04:00Is This Science?One of the most common questions computer science professors used to ask about my research went something like this: "What you're doing is very clever, and I see how it's useful, but how is it <i>science</i>?" At first, I tried coming up with convoluted explanations for why my research was actually scientific and even went and published a paper in the journal named <i>Science</i>. But I've been told that the best defense is a good offense, so at some point I switched to answering with something like "It's not. How is <i>your</i> research science?" <br /><br />Fortunately, this type of questioning has stopped. Perhaps the word got around that I myself didn't consider my research science so people just stopped asking. But the one thing that always struck me was how most computer science professors could not answer this question adequately about their own research. Which made wonder: is computer science really a <i>science</i>? It has a lot of math, but math is not science. It also has a lot of engineering -- I'm not 100% sure what the difference is between engineering and science, but I'm told there is one. <br /><br />I do find it funny that you can get a PhD in computer "science" without ever having taken a class in experimental design, in research methods or in statistics. I also find it funny that we need to put the word "science" in the name of our field: political science, actuarial science, computer science.<br /><br />I'm not sure whether cs is actually a science, but the real question is "who cares?" I don't.Luis von Ahnhttp://www.blogger.com/profile/03028143830490915261noreply@blogger.com26tag:blogger.com,1999:blog-4725006152290977601.post-70262027983829329012009-03-29T21:25:00.001-04:002009-03-29T21:25:55.498-04:00The Amazing Computer Science Diet<b>Ingredients:</b><br /><ul><li>A weight tracking site like <a href="http://www.fitday.com/">FitDay</a>. People enter some information about themselves, what they eat every day, and how much they weight. The site lets them track the number of calories they eat along with their weight. Currently, these sites don't make recommendations about what to eat.<br /><br /><li>Data mining algorithms.</ul><br /><b>Preparation Instructions:</b><br /><br />Once you have over 5 million users on your weight tracking site, perform statistics to find out what actually makes people lose weight – e.g., “by eating one more cup of yogurt every day, you can lose 1lb per month.” As opposed to other diets that are pulled out of somebody’s behind, this one will be based on millions of data points.<br /><br />Start recommending what to eat.<br /><br /><b>Alternative (Advanced) Preparation Instructions:</b><br /><br />Use collaborative filtering to determine what is the best diet for each individual. By looking at people who have similar profiles to each other (they weight the same, like to eat the same things, etc.), it may be possible to design a diet that works for you personally: “that person who is very similar to you lost weight by doing X.”Luis von Ahnhttp://www.blogger.com/profile/03028143830490915261noreply@blogger.com28tag:blogger.com,1999:blog-4725006152290977601.post-76958671717155270232009-03-22T22:17:00.002-04:002009-03-22T22:44:15.723-04:00Should You Go to Grad School?The Chronicle of Higher Education has a <a href="http://chronicle.com/jobs/news/2009/01/2009013001c.htm">provocative article</a> that strongly recommends <b>not</b> going to graduate school in the humanities. The last paragraph is particularly striking:<br /><blockquote>It's hard to tell young people that universities recognize that their idealism and energy — and lack of information — are an exploitable resource. For universities, the impact of graduate programs on the lives of those students is an acceptable externality, like dumping toxins into a river. If you cannot find a tenure-track position, your university will no longer court you; it will pretend you do not exist and will act as if your unemployability is entirely your fault. It will make you feel ashamed, and you will probably just disappear, convinced it's right rather than that the game was rigged from the beginning.</blockquote><br />While the article is specifically about graduate school in the <i>humanities</i>, I feel that some of its points are also somewhat valid for computer science. The gist of the author's argument is: incoming students are not aware that the chances of getting a faculty job are tiny; further, even when you do get that prized faculty job, the job is not <i>that</i> good. I personally think being a professor is <b>great</b> job, but I can see how some could argue against that, especially considering how hard it is to get the job. <br /><br />Let’s start with numbers. The number of people who graduate from “top 10” computer science programs every year is approximately 250. Conversely, the number of faculty positions that get filled at “top 50” research universities is about 25. That’s a ratio of about 10%, which doesn’t sound so bad (certainly not as bad as in the humanities), but there are two things that make the situation actually bad: (1) Notice that I took graduates from “top 10” programs and placed them in “top 50” programs, so this is not quite a fair comparison. The ratio becomes more like 4% if you count all graduates from “top 50” programs. At CMU, when we advertise a single faculty opening, we get approximately 500 applicants. That’s a success ratio of 0.2%. (2) The people who enroll in “top 10” computer science programs have already beaten the odds more than once. To be accepted into one of these highly ranked programs, you have to have excelled in an excellent college; to be accepted to an excellent college, you have to have excelled in high school, and so on. These are truly amazing individuals. To a large extent, they have 4.0 GPAs from college, perfect scores in the GREs, have managed to impress their professors to the point where their recommendation letters say things like “best student we’ve had in the last five years,” and by the time they graduate from college they have already published a few academic papers. All of this just to be placed in a situation where their chances of success are much less than 10%! <br /><br />At this point you start wondering if being an NFL player is easier than getting a faculty job. I don’t actually know whether this is the case, but I can say one thing: a starting professor salary is about $120,000/year, and by the time you have become insanely famous or won the Turing Award, you’re making maybe twice or thrice that amount. The minimum salary for NFL players is about $300,000/year (and that's for like the rookie backup backup kicker), and if you become insanely successful, you can be making $30 million per year or more.<br /><br />Ok, enough with the grim numbers. After all, things have worked out pretty well for me. Let me now give some reasons why the situation is not as bad as in the humanities and argue why going to graduate school in computer science is not that bad of a decision. <br /><br />First, with a PhD in computer science, you can get a job at one of many great research labs or “researchy” companies like Google, and in many ways these jobs are better than being professor -- they certainly pay more with time. This means that the chances of getting a “good job” after getting a PhD in computer science are much higher than 10%. Second, the job of a researcher or a professor is pretty awesome: for all practical purposes, <b>you have no boss</b>! Also, according to many surveys, being a scientist is one of the most “prestigious” occupations. Third, I think graduate school is extremely enjoyable: you have about 5 years to work on WHATEVER you want, with very few responsibilities whatsoever. You don’t have a set 9-5 schedule (i.e. you can stay at home for days or even entire weeks), and you get to travel throughout the world -- as a graduate student, I went for free to Mexico, Hawaii, Austria, the Netherlands, Poland, Panama, Switzerland, more than 30 places inside the continental United States, and about 5 cities in Canada. <br /><br />In the end, I think getting a PhD in computer science can be a good idea provided you actually enjoy doing research. But, (a) you should not do it for the money, and (b) you should be aware of how hard it is to get a faculty job afterwards. <br /><br />Thoughts?Luis von Ahnhttp://www.blogger.com/profile/03028143830490915261noreply@blogger.com56tag:blogger.com,1999:blog-4725006152290977601.post-1381986452519879142009-03-20T18:19:00.007-04:002009-03-20T18:26:28.738-04:0030 Pies Thrown at Me (Literally)<br><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="http://www.cs.cmu.edu/~biglou/blogImages/pie_luis.jpg"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 461px; height: 330px;" src="http://www.cs.cmu.edu/~biglou/blogImages/pie_luis.jpg" border="0" alt="" /></a><br />This is what happens at CMU when you post on your blog that you want to fail more students.Luis von Ahnhttp://www.blogger.com/profile/03028143830490915261noreply@blogger.com32tag:blogger.com,1999:blog-4725006152290977601.post-57983446494290856852009-03-17T12:51:00.007-04:002009-03-19T08:17:45.797-04:00Failing StudentsI sometimes want to fail more people in my classes. This is not because I am evil (although some people here seem to think so), but because I want the people who graduate from our computer science program to be truly the best in the world. <br /><br />When I came to Carnegie Mellon, I was surprised at the insanely high quality of our undergraduates in Computer Science. I knew the PhD program was ranked #1, but I had no idea how awesome the undergrads were. Still, I think CMU and other top universities in the US need to fail a few more students in their classes. <br /><br />The philosophy in US universities seems to be mostly one of making it really hard to get into the programs, but once you're in, the chances of graduating are really high. In fact, most rankings of American universities such as the one from US News place quite a bit of weight on four- or five-year graduation rates -- the fewer students that fail, the higher the university will be ranked. I find this counter-intuitive. While I understand that prospective students want to know that if they come here they will not be flunked, I think we all need to accept that mistakes are sometimes made in the admissions process. <br /><br />In some other countries, like Guatemala where I went to high school, the philosophy is exactly the opposite. Pretty much anybody can be accepted to any university. However, a large fraction of the people who enter end up failing out. The reason this appeals to me is that rather than making a decision based on a single test score (the SAT) and a couple of recommendation letters, universities get to test students for the span of several years before giving them a seal of approval.<br /><br />Should I be stricter with my grades?Luis von Ahnhttp://www.blogger.com/profile/03028143830490915261noreply@blogger.com106tag:blogger.com,1999:blog-4725006152290977601.post-79958627739048043252009-03-14T10:16:00.002-04:002009-03-14T10:21:53.378-04:00Irresponsible PushInspired by a popular internet company whose name I won't reveal here (you know who you are), the <a href="http://gwap.com/">GWAP</a> Web site team has started following a software engineering technique that I'm calling "irresponsible pushing." It works wonders.<br /><br /><i>Developer:</i>I've implemented a first draft of the new feature. I just need to test it. We'll be able to release it in 2-3 weeks. <br /><i>Luis:</i> Push now. Release it.<br /><i>Developer:</i>What? Live?<br /><i>Luis:</i> Yes, push push push.<br /><br />Then the untested feature is released (with bugs of course).<br /><br /><i>Luis:</i> There are bugs! It's live. People are seeing the bugs! We're gonna lose users. FIX IT. Fix it now!<br /><br />Then the developer goes nuts for the next 30 minutes fixing the issue, and voila: what was going to take 2-3 weeks took less than an hour.<br /><br />I should be writing a book about this stuff.Luis von Ahnhttp://www.blogger.com/profile/03028143830490915261noreply@blogger.com13