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Comment Pakistani Politics 101 (Score 5, Informative) 560

Imran Khan is a superstar politician that has no cultural equivalent in the United States. He's also somebody who has strong ties to the West, including going to Oxford University, having married a Brit and having been Chancellor of a British university. So this is not a dodgy politician who is rising to power in the hopes of enforcing Sharia law on the world. This guy is exactly the kind of person who could be and should be a strong ally for the West in Pakistan. On the other hand, if you wanted to find a way to alienate Pakistani moderates and those with ties to the West, this would be somebody to try and humiliate.

Comment Re:problematic Rasmussen (Score 2) 519

These algorithms aren't just going and computing an equally weighted average. In a data fusion task you can correct for some pretty extreme error terms if you can estimate them. If you understand what Rasmussen is doing and how it differs from everyone else then you can use that to your advantage.

Comment Open up the quality control steps (Score 1) 166

One thing that's horribly misleading is when prosecutors say "the likelihood of this match occurring at random is one in a quadrillion" or similar. If there aren't a quadrillion people on the planet, that statement means nothing. Also it's based on a lot of independence assumptions that may or not pan out. The irony is that the answer is out there - with all of the DNA database information that's been compiled by different law enforcement agencies, there is the ability to actually go and test to see whether there are duplicates out there, what the sharing rate is between siblings, twins and parent/children, and so on, so that you can get real measurements instead of probabilistic arguments. If current tests turn out to uniquely identify subjects, the jury should hear "this DNA uniquely identifies this person as its source".

But then as the article points out you also need to turn to the quality control aspect. Identify the potential sources of contamination, quantify those sources through experimental means. Currently agencies do not do blind tests to see what the error rate is in labs. Crime labs should be tested in blind situations to see what their quality rate is. Then you can bring out during the trial "this lab has successfully passed 100 QC tests in the last 2 years and has never failed one" or "this lab failed 2 QC tests out of 100, but the person who failed both has been discharged" or any other information that allows jurors to assess what the error rate is in the other steps in the process. Similarly, success rates are dependent on the size of the sample; if you start from 8 strands of DNA how much does your result degrade when compared with a cheek swab? We just don't have those numbers now, and there's no reason we don't.

DNA is an amazing tool in the crime database. It solves crimes that have not been solved and helps put bad guys behind bars who would have gotten away. But it is not magic or infallible. Quantifying the sources of error and presenting them during trial is the right thing to do.

Comment Sometimes distortions are good (Score 1) 202

Of course there's a lot of detail missing from the article, but something that has to be said is that some of those "annoying" distortions that they talk about are in fact valuable. The ideal camera is assumed to have a projective transformation and no chromatic aberration. But a true projective transform has some undesirable characteristics. For example, assuming that the photograph will eventually be shown on a flat surface, there will be a 1/r^2 drop off in intensity because the angle of light is being spread out across a larger area on the edge of the detector (providing for fewer photos/area) when compared with the center of the detector. Of course, if your detector is a spherical shell, that eliminates some of the issues. But even so, once you flatten it back out (onto film or onto your computer screen) the projective distortions at large angles from the image center will in some cases look worse than the typical thick-lens issues like fish-eye behavior.

Comment Re:Radiation hazard? (Score 2) 684

These radiophobes have about as much scientific respectability as the anti-vaxers, homeopaths and creationists.

Oh come on, I can't think of anyone who has been pro-VAX since the late 80s. To be criticizing luddites at the same time that you're supporting a classic mini-computer architecture is more than a bit hypocritical...

Comment Scratch, Storytelling Alice, Looking Glass (Score 2) 525

I second the comment on Scratch. My son started on it around 7yrs old and still uses it at 11. One thing he liked a lot is that in Scratch you can spend time editing your icons in a paint-like subprogram; this activity uses different parts of the brain than traditional programming, so it let him work longer on the system w/o getting burned out. He also liked the online aspects a lot. You should also look at Storytelling Alice or it's newer incarnation "Looking Glass". These were specifically designed to pull in middle school girls, but there's nothing "girly" about the environments. The basic idea is that you control a stage, add actors and props to it and then animate a "play" by telling the different actors to do things like "tell Jane to walk up to Bob", "tell Jane's left hand to hit Bob's left face", "tell Bob to say 'what was that for' " and so on. Has a lot of the "share" features of scratch too. My son started SA at the same time he started Scratch and he still uses both. They definitely teach different things, though both are drag/drop programming instead of typing free text, but they're also both efficient drag/drop programming as opposed to the VeX system which I always found incredibly painful...

Comment don't overreact to this one (Score 5, Insightful) 470

While I acknowledge the apparent insanity of the political correctness that seems to be the cause of this case, these sorts of exclusions are there for a reason. Tests should evaluate the topics they're designed to evaluate, not grade people on how "normal" their family background is. As an example, my mom was a nurse for a head start preschool and when she was going through records she noticed one kid had been labeled as having a low IQ. She could see he clearly wasn't dumb, so she looked into where the label came from. One of the main causes was that during an IQ test the kid was shown a picture of a birthday cake and he didn't recognize it and said it was a candle pie. A little research showed that he was a member of a religious group that didn't believe in celebrating birthdays, so he literally had never seen a birthday cake before.
PCness can certainly get out of control, and it sounds like it has in this case, but this is a serious topic. There are consequences for low scores on tests. This kid had been labeled dumb because he had never seen a birthday cake. When low scores are based on some sort of cultural gap, that's punishing kids who come from social groups that are out of the mainstream. Kids from _all_ social groups should be required to learn the same material, and as an example, I strongly object to parents keeping their kids from being taught evolution because of their religious beliefs. At the same time I think it's wrong to test kids on topics related to evolution (including dinosaurs) before the school has taught you about them.

Comment Teaching the curve not the median (Score 5, Interesting) 160

Of course there are many reasons that people don't finish school. Sometimes it's because they're not smart enough. Other times it's because they're bored out of their skulls, or family issues are pulling them away, or a million other reasons. Maybe this should be interpreted as yet another reason that we need to revamp schools so that they do more than just deliver a "one-size-fits-all" education to the middle of the bell curve. Education is expensive, but prison is far more expensive.

Comment Lessons from Apple about s/w only (Score 2) 630

When I worked at Apple there was a lot of discussion about whether the company should divest itself of hardware, or at least open up the clone business. The best argument against it was to look at the market cap of Microsoft at the time, which was obviously very high, but not as much larger than Apple than it would have seemed at the time. The prevailing wisdom was that if that cap was the best Microsoft could do, and it was hard to imagine anyone with a higher success than Microsoft, then Apple would be foolish to throw all its eggs into the s/w basket. Since then Apple has succeeded making great s/w that runs on great h/w and now in fact is larger than Microsoft.
I guess for some of the same reasons I'm concerned with the suggestion that the US should emphasize s/w only and give up on the h/w market.

Comment Re:FTP? (Score 2) 123

I'm pretty sure it's the same password for both. Inside the control panel there's a popup to assign each user "ftp", "sftp+ftp", or "shell+sftp+ftp" access. But if you choose either of the latter two, you have "disallow ftp" checkbox. Fairly bassackwards in my opinion, but does let you block ftp into your account - one user at a time.

Comment Re:The best option (Score 2) 126

I know what you're saying, but after a long time of both being a student and a teacher, I think there's a lot of value in actually taking notes, even if you never look at the ever again. In particular, I've consistently seen that students who record lectures perform more poorly than those taking notes. It's the whole Montessori thing -- the more senses that you can engage, the more likely you are to retain what you're being presented.

Comment energy efficiency science (Score 1) 157

Energy efficiency experiments would be especially relevant. If you're dealing with visiting students in the winter months, then an IR camera would be hugely relevant and rather cool to use: shine it at the walls and windows, see that the windows leak far more than the walls, and see that the walls don't equally protect against heat. While a good quality IR camera isn't particularly cheap, more and more utilities are purchasing them for their own energy efficiency programs (many times mandated by law), so you may be able to borrow it or co-write a grant.

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