itwbennett writes "Conventional wisdom holds that more connections make networks more resilient, but a team of mathematicians at UC Davis have found that that is only true up to a point. The team built a model to determine the ideal number of cross-network connections. 'There are some benefits to opening connections to another network. When your network is under stress, the neighboring network can help you out. But in some cases, the neighboring network can be volatile and make your problems worse. There is a trade-off,' said researcher Charles Brummit. 'We are trying to measure this trade-off and find what amount of interdependence among different networks would minimize the risk of large, spreading failures.' Brummitt's team published its work (PDF) in the Proceedings of The National Academies of Science."

langelgjm writes "Bringing a lengthy legal battle to a close, New York City's Department of Education will today release detailed evaluation reports on individual English and math teachers as a result of a request under public information laws. The city's teachers union has responded with full page ads (PDF) decrying the methodology used in the evaluations. The court's decision attempts to balance the public interest in this data against the rights of individual teachers. Across the country, a large number of states are moving to evaluate teachers based on student performance in an attempt to raise student achievement in the U.S."

ananyo writes "Even in death, the world's most accomplished parrot continues to amaze. The final experiments involving Alex – a grey parrot trained to count objects – have just been published (abstract). They show that Alex could accurately add together Arabic numerals to a sum of eight, and correctly add three small sets of objects, putting his mathematical abilities on par with (and maybe beyond) those of chimpanzees and other non-human primates."

Hugh Pickens writes "For decades, Target has collected vast amounts of data on every person who regularly walks into one of its stores. Now the NY Times Magazine reports on how companies like Target identify those unique moments in consumers' lives when their shopping habits become particularly flexible and the right advertisement or coupon can cause them to begin spending in new ways. Among life events, none are more important than the arrival of a baby, and new parents are a retailer's holy grail. In 2002, marketers at Target asked statisticians to answer an odd question: 'If we wanted to figure out if a customer is pregnant, even if she didn't want us to know, can you do that?' Specifically, the marketers said they wanted to send specially designed ads to women in their second trimester, which is when most expectant mothers begin buying all sorts of new things, like prenatal vitamins and maternity clothing. 'We knew that if we could identify them in their second trimester, there's a good chance we could capture them for years,' says statistician Andrew Pole. 'As soon as we get them buying diapers from us, they're going to start buying everything else too.' As Pole's computers crawled through the data, he was able to identify about 25 products that, when analyzed together, allowed him to assign each shopper a 'pregnancy prediction' score and he soon had a list of tens of thousands of women who were most likely pregnant. About a year after Pole created his pregnancy-prediction model, a man walked into a Target outside Minneapolis and demanded to see the manager. He was clutching coupons that had been sent to his daughter, and he was angry. 'My daughter got this in the mail!' he said. 'She's still in high school, and you're sending her coupons for baby clothes and cribs? Are you trying to encourage her to get pregnant?' The manager apologized and then called a few days later to apologize again but the father was somewhat abashed. 'It turns out there's been some activities in my house I haven't been completely aware of. She's due in August. I owe you an apology.'"

J. Alex Halderman and Nadia Heninger write in with an update to yesterday's story on RSA key security: "Yesterday Slashdot posted that RSA keys are 99.8% secure in the real world. We've been working on this concurrently, and as it turns out, the story is a bit more complicated. Those factorable keys are generated by your router and VPN, not bankofamerica.com. The geeky details are pretty nifty: we downloaded every SSL and SSH keys on the internet in a few days, did some math on 100 million digit numbers, and ended up with 27,000 private keys. (That's 0.4% of SSL keys in current use.) We posted a long blog post summarizing our findings over at Freedom to Tinker."

First time accepted submitter tonique writes "Perl Data Language (PDL) 2.4.10 has been released. Highlights of the new release are automatic multi-thread support, support for data structures larger than 2 GB and POSIX threads support. Also available is the first draft of the new PDL book. PDL is especially suitable for scientists. For those not in the know, 'PDL gives standard Perl the ability to compactly store and speedily manipulate the large N-dimensional data arrays which are the bread and butter of scientific computing.' Commercial languages used for the same purpose include MATLAB and IDL."

MrSeb writes "An Italian researcher with a penchant for retro games — or perhaps just looking for an excuse to play games in the name of science! — has used computational complexity theory to decide, once and for all, just how hard video games are. In a truly epic undertaking, Giovanni Viglietta of the University of Pisa has worked out the theoretical difficulty of 13 old games, including Pac-Man, Doom, Lemmings, Prince of Persia, and Boulder Dash. Pac-Man, with its traversal of space, is NP-hard. Doom, on the other hand, is PSPACE-hard."

You asked Carl Malamud about his experiences and hopes in the gargantuan project he's undertaken to prod the U.S. government into scanning archived documents, and to make public access (rather than availability only through special dispensation) the default for newly created, timely government data. (Malamud points out that if you have comments on what the government should be focusing on preserving, and how they should go about it, the National Archives would like to read them.) Below find answers with a mix of heartening and disheartening information about how the vast project is progressing.

First time accepted submitter CanEHdian writes "MIT news reports on research done resulting in a Faster-than-fast Fourier Transform algorithm. 'At the Association for Computing Machinery's Symposium on Discrete Algorithms (SODA) this week, a group of MIT researchers will present a new algorithm that, in a large range of practically important cases, improves on the fast Fourier transform. Under some circumstances, the improvement can be dramatic — a tenfold increase in speed. The new algorithm could be particularly useful for image compression, enabling, say, smartphones to wirelessly transmit large video files without draining their batteries or consuming their monthly bandwidth allotments.'"

Hugh Pickens writes writes "Andrei Chikatilo, 'The Butcher of Rostov,' was one of the most prolific serial killers in modern history committing at least 52 murders between 1978 and 1990 before he was caught, tried, and executed. The pattern of his murders, though, was irregular with long periods of no activity, interrupted by several murders within a short period of time. Hoping to gain insight into serial killings to prevent similar murders, Mikhail Simkin and Vwani Roychowdhury at UCLA built a mathematical model of the time pattern of the activity of Chikatilo and found the distribution of the intervals between murders follows a power law with the exponent of 1.4. The basis of their analysis is the hypothesis that 'similar to epileptic seizures, the psychotic affects, causing a serial killer to commit murder, arise from simultaneous firing of large number of neurons in the brain.' In modeling the behavior the authors didn't find that 'the killer commits murder right at the moment when neural excitation reaches a certain threshold. He needs time to plan and prepare his crime' so they built delay into their model. The killings eventually have a sedative effect, pushing the neuronal activity below the 'killing threshold' – which is why there are large intervals of time between groups of murders. 'There is at least qualitative agreement between theory and observation [PDF],' conclude the authors. 'Stats can't tell you who the perp is, but they're getting better and better at figuring out where and when the next crime might happen,' writes criminal lawyer Nathaniel Burney adding that 'catching a serial killer by focusing resources based on when and where he's likely to strike next is a hell of a lot better than relying on the junk science of behavioral profiling.'"

ananyo writes "An Irish mathematician has used a complex algorithm and millions of hours of supercomputing time to solve an important open problem in the mathematics of Sudoku, the game popularized in Japan that involves filling in a 9X9 grid of squares with the numbers 1–9 according to certain rules. Gary McGuire of University College Dublin shows in a proof posted online [PDF] that the minimum number of clues — or starting digits — needed to complete a puzzle is 17; puzzles with 16 or fewer clues do not have a unique solution. Most newspaper puzzles have around 25 clues, with the difficulty of the puzzle decreasing as more clues are given."

theodp writes "Your brain teaser prowess may win you a job at Google, but the folks at 37signals don't hire programmers based on puzzles, API quizzes, math riddles, or other parlor tricks. 'The only reliable gauge I've found for future programmer success,' explains 37signals' David Heinemeier Hansson, 'is looking at real code they've written, talking through bigger picture issues, and, if all that is swell, trying them out for size.'" Those of you who have hired employees: have you seen correlation between interview puzzle success and job competency? How should an interviewee best handle these questions?

Hugh Pickens writes "Presidential candidate Mitt Romney received eight more votes than candidate Rick Santorum or 0.007 percent of the total number of caucus votes in the Iowa caucus, 'eking out a victory' on the path to winning the Republican nomination for president but experts in statistics say Romney and Santorum actually tied. 'From a statistical point of view, you can't say Romney won any more than you can say Santorum won,' says Charles Seife, a professor of journalism at New York University who studies election error. That's because in the Iowa caucus, where voters marked their choices with check marks or by writing the candidates' names in by hand, the error rate in counting the votes, which is also done by hand is orders of magnitude above the victory margin — around 0.5 to 1 percent. There are several sources of error that could easily render eight votes meaningless." (Read on for more.)

First time accepted submitter Jack W writes "This morning's NY Times highlights the issue of learning in our public schools and the proper role of technology. The Idaho governor and his state school superintendent are advocating a legislative bill for a massive infusion of computers and on-line technology in schools and is meeting resistance from state teachers, particularly the part of the bill that requires high school students to take online courses for two of their 47 graduation credits. Superintendent Luna is quoted as saying, the computer 'becomes the textbook for every class, the research device, the advanced math calculator, the word processor and the portal to a world of information.' The article notes that the governor had received campaign contributions from technology companies and that Apple and Intel had played a part in drafting the bill."

First time accepted submitter martypantsROK writes "It's been over 15 years since my main job was a software engineer. Since then I have held positions as a Sales Engineer, then spent a few years actually doing sales as a sales rep (and found I hated it) and then got into teaching. I am still a teacher but I want to really get back into writing code for a living. In the past couple of years I've done a great deal of Javascript, PHP, Ajax, and Java, including some Android apps. So here's the question: How likely would I be to actually get a job writing code? Is continual experience in the field a must, or can a job candidate demonstrate enough current relevance and experience (minus an actual job) with a multi-year hiatus from software development jobs? I'll add, if you haven't already done the math, that I'm over 50 years old."

New submitter germansausage writes "A new study was published today in Notices of the American Mathematical Society, looking at data from 86 countries, to test the 'greater male variability hypothesis' as the primary reason for the scarcity of outstanding women mathematicians. It concludes that cultural and not biological factors are the chief causes (PDF) of the gap in math skills between men and women."

First time accepted submitter nhstar writes with an excerpt from an article in the Register: "If you're looking for a bit of light reading this holiday season, Cambridge University is here to help: they've digitized and made available online over 4,000 pages of the pioneering scientist and mathematician Sir Isaac Newton's most important works. 'Anyone, wherever they are, can see at the click of a mouse how Newton worked and how he went about developing his theories and experiments,' Cambridge University Library's digitization manager Grant Young told the BBC."

New submitter yukiloo writes "An early Christmas treat for the ordinary Joe who is stuck with a Christmas list that he cannot afford and is running out of time comes from two mathematicians (Evangelos Georgiadis, MIT, and Doron Zeilberger, Rutgers) and a computer scientist (Shalosh B. Ekhad). In their paper 'How to gamble if you're in a hurry,' they present algorithmic strategies and reclaim the world of gambling, which they say has up till recently flourished on the continuous Kolmogorov paradigm by some sugary discrete code that could make us hopefully richer, if not wiser. It's interesting since their work applies an advanced version of what seems to be the Kelly criterion."

New submitter newslash.formatb points to this Washington Post blog post, which "discusses the National Assessment of Educational Progress test (specifically, the math part). One of the school board members took it and was unable to answer any of the 60 math questions, though he guessed correctly on 10 of them. He then goes on to claim that the math isn't relevant to many people. P.S. — if you want to feel like Einstein, check out some sample questions." Maybe this is mostly about the kind of life skills that are sufficient to succeed in management.

An anonymous reader writes "17-year-old Angeloa Zhang was recently awarded the $100,000 Grand Prize in the Individual category of the Siemens Competition in Math, Science & Technology. Her project was entitled 'Design of Image-guided, Photo-thermal Controlled Drug Releasing Multifunctional Nanosystem for the Treatment of Cancer Stem Cells.' The creation is the so-called 'Swiss army knife of cancer treatment,' which allows a nanoparticle to be delivered to a tumor where it proceeds to kills cancer stem cells."