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Submission + - Why Standard Deviation Should Be Retired From Scientific Use ( 1

An anonymous reader writes: Statistician and author Nassim Taleb has a suggestion for scientific researchers: stop trying to use standard deviations in your work. He says it's misunderstood more often than not and also not the best tool for its purpose. 'It is all due to a historical accident: in 1893, the great Karl Pearson introduced the term "standard deviation" for what had been known as "root mean square error." The confusion started then: people thought it meant mean deviation. The idea stuck: every time a newspaper has attempted to clarify the concept of market "volatility", it defined it verbally as mean deviation yet produced the numerical measure of the (higher) standard deviation. But it is not just journalists who fall for the mistake: I recall seeing official documents from the department of commerce and the Federal Reserve partaking of the conflation, even regulators in statements on market volatility. What is worse, Goldstein and I found that a high number of data scientists (many with PhDs) also get confused in real life.'

Submission + - To OLPC or not to OLPC (

koubalitis writes: A friend of mine, an elementary school principaly in Greece, has asked me to help him evaluate the following situation, An ex student of the elementary school, now in his 70', wants to make a donation in the form of computer laptops. He is willing to buy a laptop for every student in the school, arround 150. He suggested getting OLPCs which cost arround 250-280euros per piece (including shipping and import taxes) but he is open to other alternatives. The principal gave me a sample OLPC XO-4 unit for evaluation. The truth is i wasn't impressed. It doesn't have support for Greek (UI or keyboard layout), the screen is too small, it feels too slow and the whole environment is too restrictive. On the other hand i liked the ruggedized plastics and the battery life. 300euros can get you a descent 11'' dual core netbook with linux preinstalled . So the question is this. Should we go for the OLPC or an alternative netbook/laptop/tablet? Does any slashdoter have experience with OLPCs?

Submission + - "Permissionless Innovation" or Why You Have No Privacy (

An anonymous reader writes: Why do apps take our information and sell it without our permission? Why is the Internet of Things a tangle of insecure devices? It all boils down to a theory — "permissionless innovation" whereby businesses and other innovators act first and apologize later. This piece explores what it is and whether, in the context of the Internet of Things, it's a danger.

Submission + - Why Birds Fly in a V Formation ( 2

sciencehabit writes: Anyone watching the autumn sky knows that migrating birds fly in a V formation, but scientists have long debated why. A new study of ibises--where researchers took to microlight planes and recorded birds strapped with GPS in-flight--finds that these big-winged birds carefully position their wingtips and sync their flapping, presumably to catch the preceding bird’s updraft and save energy during flight.

Submission + - Increasing wireless network speed by 1000%, by replacing packets with algebra (

MrSeb writes: "A team of researchers from MIT, Caltech, Harvard, and other universities in Europe, have devised a way of boosting the performance of wireless networks by up to 10 times — without increasing transmission power, adding more base stations, or using more wireless spectrum. The researchers’ creation, coded TCP, is a novel way of transmitting data so that lost packets don’t result in higher latency or re-sent data. With coded TCP, blocks of packets are clumped together and then transformed into algebraic equations that describe the packets. If part of the message is lost, the receiver can solve the equation to derive the missing data. The process of solving the equations is simple and linear, meaning it doesn’t require much processing on behalf of the router/smartphone/laptop. In testing, the coded TCP resulted in some dramatic improvements. MIT found that campus WiFi (2% packet loss) jumped from 1Mbps to 16Mbps. On a fast-moving train (5% packet loss), the connection speed jumped from 0.5Mbps to 13.5Mbps. Moving forward, coded TCP is expected to have huge repercussions on the performance of LTE and WiFi networks — and the technology has already been commercially licensed to several hardware makers."

Submission + - Large Solar Flare To Glance Off Earth ( 1

JoeRobe writes: According to, a major X5 solar flare is on it's way to deliver a glancing blow to the Earth's magnetic field. This is the second x-class flare to be released by the same sunspot in the past few days, the first being an X1. In both cases, the sunspot (spot 1429) was not directly facing Earth, but it is still active, and poses a threat for a large, Earth-directed flare in the next few days.

Submission + - How To Get Anything Past TSA's Body Scanners (

OverTheGeicoE writes: Blogger and anti-TSA activist Jonathan Corbett has just published a video showing how to bring any object through any type of TSA body scanner without it being detected. In his demonstration he places a small metal case in a side pocket of his shirt he sewed on himself. He then proceeds through two different body scanners, one millimeter-wave and one X-ray, while his video camera records through the X-ray carry on inspection process. When he returns to his bin to collect his items, he drops his metal case next to the video camera, showing that it made it through the scanner undetected. Corbett's demonstration seems to confirm the 2010 conclusions of Kaufman and Carlson, who wrote that 'an object such as a wire or a boxcutter blade, taped to the side of the body, or even a small gun in the same location, will be invisible.'

Submission + - Chevy Volt Passes Safety Investigation (

An anonymous reader writes: A few months ago, reports of battery fires from crashed Chevy Volts caused the National Highway Traffic Safety Administration to open an investigation into the type of batteries used in the Volt and other EVs. That investigation has now concluded, and the NHTSA says the cars are safe. 'The agency and General Motors Co. know of no fires in real-world crashes. GM and federal safety officials say they believe the fires were caused by coolant leaking from damaged plastic casing around the batteries after side-impact collisions. The coolant caused an electrical short, which sparked battery fires seven days to three weeks after the crashes. GM announced earlier this month that it will add steel plates to about 12,000 existing Volts to protect the batteries in the event of a crash.'
United States

Submission + - Steve Jobs Told Obama Made-in-the-USA Days Over 9

theodp writes: At his Last Supper with Steve Jobs, reports the NY Times, President Obama had a question for Jobs: What would it take to make iPhones in the United States? 'Those jobs aren't coming back,' Jobs replied. The president's question touched upon a central conviction at Apple: It isn't just that workers are cheaper abroad; Apple execs believe the vast scale of overseas factories as well as the flexibility, diligence and industrial skills of foreign workers have so outpaced their American counterparts that Made in the U.S.A.' is no longer a viable option for most Apple products. 'The speed and flexibility is breathtaking,' a former Apple exec gushed, describing how 8,000 workers were once roused from company dormitories at midnight to address a last-minute Apple design change, given a biscuit and a cup of tea, guided to a workstation and within half an hour started a 12-hour shift fitting glass screens into beveled frames. 'There's no American plant that can match that.' What's vexed Obama as well as economists and policy makers is that Apple — and many of its hi-tech peers — are not nearly as avid in creating American jobs as other famous companies were in their heydays. 'We don't have an obligation to solve America's problems,' a current Apple exec is quoted as saying. 'Our only obligation is making the best product possible.'

Submission + - Ray Tracer in JavaScript (

mikejuk writes: Just when you thought you had seen everything that could impress in JavaScript, along comes another crazy application.. Now we have a ray tracer that creates very realistic 3D scenes right in your browser. Probably not up to creating the next CGI movie but still a lot of fun to play with.

Submission + - Why Google should buy Sprint: to save mobile (

GMGruman writes: Is one tech oligarch better than another? I think in the case of the development of mobile broadband, the answer is yes. And thus, Google should buy Sprint to turn its cellular network into an effective, powerful wireless network that delivers on the carriers' decade-old promise of untethered information flow. The alternative is clear: More dark hints by carriers such as AT&T that they'll meter the heck out of wireless broadband, all while blaming the users whom they happily sell 3G service to for using it too much. The comfy telecom oligarchy needs a shakeup. Google could do it, and further its own cloud, Android, and Chrome ambitions along the way.

Submission + - Virgin Galactic Spaceship the Tip of The Iceberg (

YIAAL writes: The Virgin Galactic Spaceship Two rollout got a fair amount of attention, but Rand Simberg, writing in Popular Mechanics, says it's just the beginning:

Despite all of the Virgin-focused hoopla, there is a lot more going on in Mojave these days than just Virgin Galactic and Scaled Composites. And even for those two companies, there is more to space going on in Mojave than suborbital tourism. . . . XCOR Aerospace, located next door to one of Scaled's hangars, continues to develop its own suborbital tourist vehicle, the Lynx. While it won't initially get all the way to the 62-mile altitude considered to be the threshold of space, it will still allow long weightless periods for its passenger and a smaller experiment, with the opportunity to go higher and longer with follow-on versions. Meanwhile, just a couple of blocks down the road, Masten Space Systems, fresh off its recent surprise win over Texas' Armadillo Aerospace in the Northrop Grumman Lunar Landing Challenge, plans to start flying to altitudes far beyond the meager few hundred feet needed to win that prize. According to business development manager Michael Mealling, "about half of next year's flights will be in the 1500- to 10,000-foot range. Toward the end of the year we'll be breaking through the 100,000-foot [about 20 miles, or about a third of the altitude needed for official spaceflight] barrier."

Are we seeing a critical mass of innovative space companies, something like the explosion of computer companies in the mid-1970s? Let's hope it's similarly fruitful.

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