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User: drfireman

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  1. Re:PET/MRI and statistics are poor bed partners on Cell Phone Use Tied To Changes In Brain Activity · · Score: 1

    I agree that this is a very clear-cut point. The abstract simply does not say whether or not that p value is corrected. The article does. I refer you specifically to table 2, which provides the corrected p values for both of the ROIs. It lists them both as 0.05. I apologize if I'm reading this wrong, but I can't fathom what the basis could be for your disagreement, unless you were forced to guess without access to the full article.

    If you're going to dispute my other two points, then I'm comfortable with that. There's a tidy little literature on the stupidity of retrospective power analysis. So far as I know, there's no opposing literature whatsoever. But of course academic statisticians are argumentative, so I'm sure you can find someone to disagree with just about anything, even if no one (to my knowledge) has been willing to make the point in a decent journal.

    I'd also be shocked if you could get a knowledgeable statistician to sign on to the view that there's an accepted adequate number of observations for a t-test without any other details about the study. A simple power analysis seems like it would dispute that pretty readily (I won't insult anyone by posting numbers, at least not yet). But since you haven't made any argument, I can't really argue the point.

  2. Re:PET/MRI and statistics are poor bed partners on Cell Phone Use Tied To Changes In Brain Activity · · Score: 1

    I think your third point misses the point. 47 participants probably is reasonable, but there is no such thing as an "accepted number for a t-test" without some prior estimate of the effect size you're looking for and the expected variability. All that said, there is absolutely no point in arguing about an observed effect on the basis of its prior power (aka retrospective power analysis). Once you have the results, the only thing that matters is whether or not the statistics were done correctly (and then, of course, what you're going to make of it, etc.). I know you know this, but it bears repeating.

    Also, I believe p=0.004 is the uncorrected p value. Brain imaging studies generally pay a heavy price in terms of correction for multiple comparisons. In this case, the corrected p value was 0.05, which just meets the normal arbitrary standard. From my quick reading, the more impressive (statistically) result is the relationship between the electric field magnitude and the change in signal associated with on vs. off. That came in at 0.001, uncorrected.

  3. Re:PET/MRI and statistics are poor bed partners on Cell Phone Use Tied To Changes In Brain Activity · · Score: 1

    Do you have some basis for saying that 47 participants is too few? If you think you do, then I urge you to do some more careful reading of your texts on power analysis. And I specifically urge you to read some of the many fine articles by statisticians on the evils of retrospective power analysis. The bottom line of all this is that once the study is done, and there are findings, it doesn't matter if it had too few subjects. Either the statistics are valid or they're not. In this case, they're... well, they're close enough to valid that I'll give it to them. No study is perfect, but it's at best misleading to describe a study as invalid because it doesn't have some arbitrary number of subjects.

    If I'm doing you an injustice, and you have some legitimate reason to suspect that their methods have in inflated false positive rate, then please post more details, I'm always happy to learn new things.

    I will agree, though, that imaging studies don't tell us nearly as much about human behavior as many people seem to think, although the worst offenders are not studies like this, but cognitive studies that make unsupported claims about what processes underly patterns of activation. And of course you're right that news outlets are likely to jump on this to make some kind of unsupported point about cancer.

  4. Re:Crappy Study or Crappy Reporting? on Cell Phone Use Tied To Changes In Brain Activity · · Score: 1

    I've read the JAMA article. They report effects in the temporal pole, which is in the temporal lobe, but not that part that's associated with auditory processing. There are also frontal lobe effects, not too near the part of the frontal lobe that's directly involved in speech. It's also hard to argue that the effect is due to listening, because subjects didn't know when the phones were on or off, and for the results to have worked out, they'd have to have been listening more when the phones were on than off.

    The confusing paragraph you cite is easy to explain. There's a difference between "overall" effects and local effects. They found effects localized to where the phone was, but not overall effects in the whole brain. This is just a sloppy way of pointing out that the effects they found were localized to where the cell phone was.

  5. Re:Unsure on Cell Phone Use Tied To Changes In Brain Activity · · Score: 1

    Actually, both researchers and and the NIH are reasonably clever, for the most part (and they're the same people, by the way). The clueless people are idiots who have no scientific training or experience whatsoever and think they can offer appropriate scientific criticisms of a study they haven't read.

  6. Re:Unsure on Cell Phone Use Tied To Changes In Brain Activity · · Score: 1

    Actually, they did use a reference condition with another device that didn't involve radio waves. It was a cell phone turned off. This is a much more appropriate control than what you suggest, and is a pretty good control for this study. Listening to recordings on headphones would be a very poorly chosen control condition, for obvious reasons.

  7. Re:Unsure on Cell Phone Use Tied To Changes In Brain Activity · · Score: 1

    The part of the temporal lobe they found was in/near the temporal pole, which is not particularly related to hearing.

  8. Re:Great book on LotR Rewritten From a Mordor Perspective · · Score: 1

    Ignoring the sarcasm, I guess your point is that copyright has nothing to do with promoting great work, only crap. This is obviously ridiculous. Crap will always be in vastly greater supply, and copyright means we'll get a lot more of both. There would certainly be both brilliant work and utter crap with or without copyright. But since copyright creates a financial incentive, it probably promotes crap more than it promotes good work. But that's probably a really narrow difference. I could equally well argue that without copyright, only the independently wealthy would be able to devote their time to creating great works of art. Even with copyright, there is very little opportunity to earn a living as an artist.

    Copyright law in the US is a pile of garbage that does much more harm than good to the arts. But the absence of copyright law would also be a pile of garbage that would do much more harm than good to the arts.

  9. Re:Short rant about e-books. on E-Book Lending Stands Up To Corporate Mongering · · Score: 1

    As a very conflicted Kindle owner, I couldn't agree more. I'm especially concerned that I might not be able to read the ebooks I buy today on the device I want to use tomorrow. If that device is a Nook, or a Sony reader, or some new software that's better than what Amazon provides, then I have to ditch my entire ebook library or maintain multiple devices. Truthfully, I'm hoping that the licensing terms will change during my lifetime, and I won't have to feel like a criminal for wanting to do useful things with my e-books. I'm not optimistic, but then again, I wasn't optimistic about the music industry giving up on DRM either. I do find the Kindle much more comfortable than reading books on paper, at least for books that are all text, and I've been willing to overlook these issues partly because I still consider it an early adopter technology.

  10. Re:I disapprove of Approval Voting on New Hampshire Bill Could Lead To Adoption of Approval Voting · · Score: 1

    Approval voting is probably the best method that has a chance in hell of being adopted any time soon, and it addresses some of the most disturbing weaknesses of the current system. I'm happy with that. If you think you can get Schulze voting approved, go for it. But you're extremely misguided in advising people not to advocate approval voting, which is realistically attainable (Schulze voting is not) and a huge improvement, even if it's "broken." Remember, no method is perfect, so if we agree with you that we should not adopt a broken method, then we should not vote, period.

  11. Re:Bad Science book on Bad Science Writer Talks About the Placebo Effect *NSFW* · · Score: 4, Informative

    Let's not forget his column/blog (badscience.net).

  12. very silly discussion on Facebook Opens Up Home Addresses and Phone Numbers · · Score: 1

    Facebook is no more evil this week than it was last. According to the article, apps can now request access to your private info. When an app requests your ifno, you can say yes or no. If you trust facebook to implement this as stated (one poster has already tried it and found it to be as described), then what's the big deal? Apps could also just ask you for your social security number, or your credit card numbers, this just makes it easier for users who were going to be agreeable. Who cares? And if you don't trust facebook, then you don't have private information on there anyway. So again, what's the big deal? This is a complete non-story that's been escalated into some kind of scare story by people who can't read.

  13. Re:why stop at addresses and phone numbers? on Facebook Opens Up Home Addresses and Phone Numbers · · Score: 1

    That's just stupid. Some people find fb useful and know how to use it safely. Frankly, anyone who falls victim to this is just a complete idiot. So yes, complete idiots should delete their accounts immediately (aso their email accounts and their phone accounts, and they should remove doors from their houses). Everyone else has nothing to worry about. I don't know why this is even news. Most people, like me, probably assumed that apps could request whatever they wanted. Apps could already just ask you for your phone number if they really wanted it.

  14. Re:A really nasty trick on Google To Drop Support For H.264 In Chrome · · Score: 1

    If you're saying it's FUD that firefox users will heave to pay for a decoder, then please explain how we can legally obtain a free one.

    Using OS libraries doesn't address the problem, it just means you're using a commercial OS, or a free OS with a commercial decoder installed. $.20 is indeed very reasonable, but unless they're legally compelled to maintain that price level through the 2028, I'm skeptical. Drug dealers offer an even better deal -- first one's free.

    The fact that mozilla has enough cash to deal with this is irrelevant. Not everyone who might want to write software to support web standards has that kind of money. Right now, I can write a free, functional web browser if I want, and distribute it for free to whomever I like. If H.264 is adopted, I won't be able to. No one without massive capital will be able to, not for at least 17 years.

    As an aside, I'm not arguing as if WebM is unencumbered. When that turns out to be a problem, I'll fault Google for failing to dodge patent potholes then. But for now, I'm willing to believe that if they say it will be BSD-licensed (or whatever), it will be.

  15. Re:A really nasty trick on Google To Drop Support For H.264 In Chrome · · Score: 1

    Anything that slows or halts the transition to a standard that depends on commercialized patents is good for users. If MPEG LA has its way, everyone who uses firefox (for example) will have to buy a proprietary plug-in to use youtube. If Google has its way (which I don't like either, but for different reasons), we won't. We shouldn't allow web video to be held hostage for the next 18 years by large corporations, whether it's a single corporation or a coalition. If WebM turns out to have patent troubles, that's a separate issue -- you can't fault Google because other parties want to prevent them from making it available for free. I really don't think the phrase "open standard" has any useful meaning here. H.264 is not open in any way that helps anyone.

    As an aside, I really don't care if it advances Google's agenda, unless you can describe how that agenda hurts me. My devices are going to become slightly less spiffy (not obsolete) about ten minutes faster? Who cares? Google wants to delay the transition away from flash to hurt Apple? That's fine with me -- protecting Apple is not a good reason to rush to adopt an expensive commercial product as a web standard.

  16. Re:race to the bottom on Why Published Research Findings Are Often False · · Score: 1

    Well, it's mostly just my impression, although lately it doesn't seem like a very close call. But I did once see a poster at a conference that dissected portrayals of various occupations in a broad selection of movies. It was partly tongue-in-cheek, but the end result was that in terms of negative portrayals, the leading occupation was murderer (I guess that's an occupation), and coming in at #2 was scientist.

  17. Re:race to the bottom on Why Published Research Findings Are Often False · · Score: 1

    I'm torn about this. On the one hand, it's certainly true that science is overwhelmingly portrayed in mainstream American society as evil, or at least not good, and anything that contributes to this view is upsetting. On the other hand, there are some serious structural problems with the way science is practiced that desperately need to be addressed, and when someone like John Ioannidis or Jonathan Schooler points them out, I think it's important that they be taken very seriously. These problems have especially immediate implications when we're talking about things like drug studies, but they span the sciences.

    It's tempting to reconcile these opposing motivations by saying that science should handle these things in-house. But scientists don't have a good record when it comes to self-policing. So I'm not sure how to feel about articles like this. My sincere (possibly futile) hope is that these things will be reported in a way that makes it clear that improving science is a worthwhile goal, and does not imply that all previous findings are false. Note that Ioannidis's articles have some sensational titles, but the contents are much more level-headed.

  18. Re:Yeah i was thinking about that. on Electric Cars May Be Made Noisier By Law · · Score: 1

    Everyone is irresponsible occasionally, and it's far from irrational to be irresponsible in this case. For the entirety of my life, I've never been surprised by a gas-powered car sneaking up on me, because they're noisy.

    You're also making a very bizarre and patently false assumption that pedestrians always know when to look. Perhaps you're only familiar with urban living? When I take my dog or my child for a walk, I need to know whenever a car is coming up behind me -- not just when I'm crossing a street, or at well-defined checkpoints, but on a continual basis. It's just not reasonable to tell me that I should continually swivel my head around every time I take a walk. Right now, when I hear a car coming up behind me, I turn around, decide if the driver is a threat, and take appropriate action. Fortunately, the most erratic drivers in my neighborhood don't drive electric cars yet. But that will change.

  19. Re:Yeah i was thinking about that. on Electric Cars May Be Made Noisier By Law · · Score: 1

    It's nonsense to say that tire noise is sufficient. Tire noise is quieter than engine noise, so if you rely entirely on tire noise, there will be circumstances (wind, distant lawnmower noises, etc.) in which the tire noise is not audible and engine noise would be. The bottom line is that making cars quieter violates reasonable expectations. Everyone who's grown up with cars knows how to tell the difference between a car coming, no car coming, and can't-tell. If you put a lot of cars out there that are much quieter than the quietest cars previously on the road, then people will inevitably sometimes think there's no car coming when in fact they can't tell.

    Also, it sounds like you've never had a pedestrian jump out in front of you from behind a parked car. It's easy to show that you can be driving 20km/hr and have no chance whatsoever of avoiding a pedestrian if they happen to run out just at the wrong time. Some of those pedestrians were going to get hit no matter what, but some of them might have heard engine noise.

  20. Re:Yeah i was thinking about that. on Electric Cars May Be Made Noisier By Law · · Score: 1

    The issue here isn't protecting people who act unreasonably, it's protecting people who act reasonably.

  21. Re:Yeah i was thinking about that. on Electric Cars May Be Made Noisier By Law · · Score: 1

    It's not an arms race. Once the cars are loud enough to hear on a quiet street, nobody needs them to get any louder. The problem is that everyone on the planet has grown up in an environment in which relative quiet means no car is coming. It doesn't matter one bit if the car sounds are drowned out. Nobody steps out into the street without looking just because it's really noisy and they can't tell if a car's coming or not. People used to do that, but they're all dead now.

    Tire noise is not always audible, certainly not above a light wind if the street is dry. Everyone who lives in the suburbs and goes for a walk occasionally knows this. Electric cars can make useful noises without being anywhere near as noisy as gas-powered cars.

    The issue here is not requiring everything that might hurt you to carry a warning. The issue is whether or not it's okay to have things that have carried warnings for the entire lifetime of everyone now living to suddenly stop doing so. It's not.

    Bicycle riders can indeed hurt you, but (a) they tend to be less fatal than cars when they strike pedestrians; (b) bicyclists are aware of the fact that they're inaudible (in fact, many have bells or horns); and (c) nobody on this planet has grown up in an environment in which bicycles always make loud noises. Should we be worried about defective noise makers on cars? Probably not if they're as rare as defective steering, defective drivers, etc.

  22. obvious problem on Sahara Solar To Power Half the World By 2050 · · Score: 1

    Some guy who lives in the Sahara gets a dog, decides to put in a fence, digs a hole, cuts through a cable, and boom -- no electricity for half the world.

  23. this phenomenon is not specific to games on Have I Lost My Gaming Mojo? · · Score: 2, Insightful

    Most people, as they get older, find it harder to get into new games, new music, new movies, new food, new sports, new friends, etc. Getting into new stuff takes effort, uninterrupted time, attention span, and a certain kind of ignorance that comes with youth and that lets you see warmed-over crap as exciting and fresh. You eventually reach an age at which it's hard to find anything that seems genuinely worth your excitement; you get jaded . It doesn't work that way for everyone in every arena, but that's generally how it goes.

  24. probably two separate issues on Traffic Jams In Your Brain · · Score: 2, Insightful

    Asking why we can't do three-digit multiplication quickly even though our brains is complex is sort of like asking why a toaster can't tell you ratios of voltages even though it has resistors in it. It's the difference between what a machine does and how it works. Brains are fabulously complex, but one thing they weren't built for is three-digit multiplication. Does the brain "know" how to do multiplication really really fast? Yes, of course, there are all kinds of things going on in the brain that involve multiplication. Does it know how to do it with numbers that come in through the ears, and spew the answer out through your mouth? No, brains weren't built to do that. They were, however, built (so to speak) to do much more complicated (but different) things, like recognizing threats and understanding spoken language.

    I don't know how good the router analogy will turn out to be, but it's not exactly breaking news that some things need attended, more-or-less serial processing, and that mental arithmetic is one of them. The things that don't need as much attention are things that are evolutionarily old and more or less built-in. Extremely overlearned tasks can fake it sometimes. Guys like Hal Pashler and Stan Dehaene are always making progress into understanding how and why these things work, but the idea of processing bottlenecks in cognitive function is very old. The router analogy is probably a bad one, because it's unlikely that the brain's router lives in any very specific place. It's more likely a property of how the brain adapts to tasks it wasn't designed for.

  25. Ioannidis is well worth reading on Meta-Research Debunks Medical Study Findings · · Score: 1

    Ioannidis has a long history of publishing articles describing basic mistakes researchers make in understanding and reporting research. Although this titles of his articles have a sort of "the sky is falling" kind of quality, the contents of the articles are very level-headed. He certainly does not argue that science or scientific findings are in general worthless, only that there are things we should correct in scientific practice that would improve the situation markedly. In broad outline, no practicing scientist could possibly disagree, although of course the particulars are always up for debate. Although he covers some ground that others have as well, he seems to have made it a focus of his career, and writes more level-headedly than most.

    Many of his articles are easily readable by non-specialists, and at least a few are available for free (see pubmed).