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Comment Smith is easy to underestimate (Score 2) 292

I met this guy once in a real meeting with genuine conversation. He's actually very bright. He went to Yale for instance. I know that's no guarantee you haven't been infected with some ideology virus, but ask yourself: if you had been to Yale and wanted a lot of red meat eating, capital punishment cheering, cousin marrying Texans to send you to Congress, what sort of stuff would you have to say in public? I really think that thought is at the bottom of a lot of his stuff. I think that he'll be okay as long as the spotlight isn't too bright. We just won't see a lot of progressive science leadership from him.

Comment Re:USB Microscope (Score 1) 118

Years ago when my girls were little, we had one of these from Logitech. It worked fine (came with some software). It was essentially just a camera with some close-up capability. I can also recommend little $10 portable microscopes from, among others, Edmund Scientific. They're about the size of a cigar case. They're a small hassle to get focused but you can take them anywhere. They even have a little light.

Comment Re:Power Analysis (Score 1) 315

No, I didn't read the paper. But I've done power analyses plenty of times and I know that with tiny expected effects 40 or 50 isn't enough. It's enough if you're expecting moderate or large effects, but you can't seriously propose that if you're trying to prove that the effect size is zero. You can't take Bem's effects as proper estimates of what to expect in your power analysis if you've got theoretical reason to suppose that Bem's results were overstated in his data set. If you're actually setting out to prove a null you can't skimp on sample size. Their idea was to refute the original paper, not just jab at it, and they needed a killer case to do that. N of 50 won't do, and even N of 150 won't do. If you're going to prove nothing is going on, you have to stomp on the finding, and N = 500 and upwards is going to be what's required. This sort of minimalist study design is just going to keep things going.

Comment Power Analysis (Score 2) 315

I don't think ESP is real either, but the journal editors had first class reasons to reject the replication-failure paper. The sample size of each replication was 50. They tried 3 times, for a total of 150. It is very hard to prove a null hypothesis--this is not the same as failing to support a research hypothesis. Roughly, the quality of support for a research hypothesis is measured in terms of Type I error, which is assessed by p levels (e.g., p LT .05). The quality of support for a null hypothesis (and not everyone agrees that this is possible in principle) is measured in terms of Type II error, or the power of a statistical test. The power of a test depends on the sample size, the expected effect size, and which statistic (e.g., r, t) is in use. A replication test of the original ESP paper must have substantial power because the expected effect size is, well, zero. To find a tiny effect size, which would be the fair design, requires more than N=50. Doing the same underpowered study three times doesn't help very much, but even N=150 wouldn't be decisive. The journal in question is one of the most prominent in psychology. Whether they publish replications or not (and they do--replications aren't done for their own sake, they are implicit in follow-up studies), they certainly shouldn't publish bad ones.

Comment People are interested in themselves (Score 3, Insightful) 291

Organize the talk by their jobs. Show them how it all works when they do what they do, and where it's most likely to fail or slow down when they do various things. You'll probably go back to a couple of key slides frequently as you move from one major job type to another, but you'll adapt to your listeners. Everybody is interested in themselves. For a big finish show them how all their jobs move together in the common system. Avoid the natural mistake of organizing it by your own job.

Comment UMCOR (Score 1) 570

The United Methodist Committee on Relief does disaster assistance - water, blankets, some meds. They're usually one of the first on the scene. The church donates all the administration, so every dollar you give buys a dollar of relief. Just drop a check off at the closest Methodist Church.

Comment CPM (Score 4, Funny) 306

My first self-owned computer was a Kaypro 4-84. The OS was CPM and the machine came with 64K (yes, K) of RAM. When it booted up the screen said it had 63K of RAM. I thought I had been ripped off so I called the company. The tech explained that the other 1K was being used by the OS. So I don't think Windows 8 is going to impress me.

Comment Re:The Net is no Substitution for University (Score 1) 393

I've thought for years that in a generation the distinction between haves and have-nots won't be private v. public universities, but online v. human instruction. Online coursework didn't used to be very cheap for universities - they said it was, but conveniently forgot to include overhead or support in their calculations - but now with so many people able to work the web and post stuff, it probably is. I notice that some universities charge a surcharge for online courses, to support the capital investment, etc. For the essentially exclusive online schools, the real cost saving is in the faculty - lots of that online stuff is taught by people who would never get university appointments (disclaimer: I'm an in-person actual human university prof). The very worst, I think, are the online companies that prey on our troops in the Middle East. One allows a soldier to get an AA degree by taking one course and getting lots of life experience and military training credit. The online operations have their own accrediting agency and not all US universities respect that accreditation when assessing applicants (e.g., for grad school). The www is far more useful for some disciplines than others. Computer stuff is an example of where keeping up to the minute is pretty important, and there's lots of good instruction available. But other disciplines aren't so amenable - history, philosophy, social sciences. Slashdot readers might in the group where online work is most appropriate, and I'm seeing a lot of divided opinions even here.
Space

Super-Earths Discovered Orbiting Nearby, Sun-Like Star 242

likuidkewl writes "Two super-earths, 5 and 7.5 times the size of our home, were found to be orbiting 61 Virginis a mere 28 light years away. 'These detections indicate that low-mass planets are quite common around nearby stars. The discovery of potentially habitable nearby worlds may be just a few years away,' said Steven Vogt, a professor of astronomy and astrophysics at UCSC. Among hundreds of our nearest stellar neighbors, 61 Vir stands out as being the most nearly similar to the Sun in terms of age, mass, and other essential properties."

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