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+ - The Game Theory of Life->

Submitted by Anonymous Coward
An anonymous reader writes "In what appears to be the first study of its kind, computer scientists report that an algorithm discovered more than 50 years ago in game theory and now widely used in machine learning is mathematically identical to the equations used to describe the distribution of genes within a population of organisms. Researchers may be able to use the algorithm, which is surprisingly simple and powerful, to better understand how natural selection works and how populations maintain their genetic diversity."
Link to Original Source

+ - Project Euler shut down indefinitely->

Submitted by Big_Oh
Big_Oh (623570) writes "Project Euler, a list of math-centric programming exercises and community of solvers, is offline indefinitely. The website now contains a terse message, beginning "Due to the discovery of a serious security issue a decision was made on Sunday 15 June 2014 to take down the website." It continues with standard we're-sure-this-is-no-big-deal clause, and then recommends changing passwords on other sites."
Link to Original Source

+ - NADA Is Terrified Of Tesla

Submitted by cartechboy
cartechboy (2660665) writes "It's no secret that the National Automobile Dealers Association has been trying to block Tesla from selling cars directly from consumers, but to date, it has been defeated countless times in many states. Now NADA put out a release and promotional video touting the benefits of dealer franchises, something Tesla has shunned. NADA mentions price competition, consumer safety, local economic benefits, and added value. While NADA argues its points, there's no question that Tesla could easily turn around and argue right back with valid counter points. There may be some truth to NADA's claims, but there are some gaping holes in the arguments that can't be ignored, and I'm sure Tesla won't. Hey NADA, you scared?"

Comment: How D-Wave works (Score 1) 224

Remember analog computers? You would set up a circuit so that the voltage in one place was the answer to your computation, and then instead of calculating the answer you would *measure* the answer. We stopped thinking about them because it was tricky to set up the circuit for each calculation, but once you had it set up the computation would happen at the speed of electrons.

The D-Wave computer is similar to this. Given a polynomial in many variables (with positive real coefficients, and the variables only take the values 0 and 1), you might like to find the assignment to the variables that minimizes the polynomial. So D-Wave sets up a thermodynamic system whose steady state can be *measured* and gives an assignment to the variables that makes your polynomial small. Systems will naturally try to minimize their energy, and so the assignment is likely to be your perfect minimum (repeat 100 times, and the best assignment is likely to have appeared).

The question is whether the system minimizes its energy by classical thermodynamic flow (super fast), or by quantum effects (super-duper fast). It is, for that particular sort of problem, *much* faster than anything else ever. It had seemed to be so much faster and accurate that it had to be using quantum effects. But now somebody has found a faster way to do it classically, so that it isn't *that* much faster. For those of you in the know, the question isn't speed but the rate of growth of the speed: is the ratio of speed-up growing polynomially in the input, or exponentially?

Comment: Re:S/T Ratio DOES matter (Score 1) 343

by Big_Oh (#38983133) Attached to: Three Unexpected Data Points Describe Elementary School Quality
As an instructor, I enjoy teaching a small class much more than teaching a large one. Presumably, teachers who are enjoying their work will do better than teachers who aren't. In my personal experience, the quality of the education I provide varies wildly from class to class and semester to semester. Within a classroom, there are always a few students who "get me" and vice versa, and always a few that I just don't jive with.

Comment: Re:There is never a magic bullet (Score 1) 343

by Big_Oh (#38983077) Attached to: Three Unexpected Data Points Describe Elementary School Quality
SAT scores are bad to correlate with because they have nonobvious selection biases. For example, the state schools in Indiana don't require the SAT at all, so only those students who are hoping to leave the state for school take the SAT. This inflates the scores dramatically. In other places (Vermont, perhaps?) the SAT is required for all colleges, and so essentially all high school students take the SAT, deflating scores. Throw in the effect of guidance counselors recommending school A instead of school B, and SAT (by state, or by school) make very poor predictors. Even by student, it doesn't do very well, but that's another post.

Porting Lemmings In 36 Hours 154

Posted by Soulskill
from the first-in-line dept.
An anonymous reader writes "Aaron Ardiri challenged himself to port his classic PalmOS version of Lemmings to the iPhone, Palm Pre, Mac, and Windows. The porting was done using his own dev environment, which creates native C versions of the game. He liveblogged the whole thing, and finished after only 36 hours with an iPhone version and a Palm Pre version awaiting submission, and free versions for Windows and Mac available on his site."

Comment: "having a plan" is not the same as "planning" (Score 1) 555

by Big_Oh (#31485428) Attached to: US Intelligence Planned To Destroy WikiLeaks
The story isn't that they planned to do this, and it is unreasonable to conclude that the plan was ineffective. The story is that they developed a plan to do this. I'd be shocked if China didn't have a plan (or a dozen plans) for the conquering of Taiwan. I'd be horrified if they actually planned to invade Taiwan. Military people need to practice between real action, and drawing up contingency plans is a way to do that. It's healthy, and prevents much stupidity from seeing the light of day. For example, from thinking about this, they may be led to realize that net censorship is ineffective and counterproductive unless it is undertaken on a brazen scale. That would be good, and IMHO more likely than that it will lead to real attacks on Wikileaks.
The Almighty Buck

Forrester Says Tech Downturn Is "Unofficially Over" 130

Posted by kdawson
from the unofficial-whoopee dept.
alphadogg writes "The US IT market will grow by 6.6% as high-tech spending rebounds in 2010, according to Forrester Research's latest estimates. The research firm based its projections on data reported for 2009, though its fourth quarter numbers are incomplete. Forrester says hints of a recovery surfaced in the third quarter, and now the company expects the global IT market to grow by 8.1% in 2010. Forrester's US and Global IT Market Outlook: Q4 2009 reads: 'The tech downturn of 2008 and 2009 is unofficially over, while the Q3 2009 data for the US and the global market showed continued declines in tech purchases (as we expected). We predict that the Q4 2009 data will show a small increase in buying activity, or at worst, just a small decline.'"

Canadian Blood Services Promotes Pseudoscience 219

Posted by samzenpus
from the type-A-negative-personality dept.
trianglecat writes "The not-for-profit agency Canadian Blood Services has a section of their website based on the Japanese cultural belief of ketsueki-gata, which claims that a person's blood group determines or predicts their personality type. Disappointing for a self-proclaimed 'science-based' organization. The Ottawa Skeptics, based in the nation's capital, appear to be taking some action."

Comment: Re:The way math is structured is disconnected from (Score 1) 677

by Big_Oh (#28396879) Attached to: A Mathematician's Lament — an Indictment of US Math Education
You've missed the point: it isn't mathematicians who've made it overly complicated. It is people responsible for /teaching/ math. Mathematicians have made it exactly as complicated as it needs to be, no more and no less. But many textbook authors have taken that complicatedness and introduced it into areas where it isn't needed, out of a lack of understanding as to why it was needed in the first place. An example from TFA: mathematicians prefer "|x-5|2" over "x is between 3 and 7" because the former generalizes naturally to arbitrary metric spaces (like R^n). But until somebody is ready to talk about distance in R^2, and circles and such, the latter should be preferred. It uses less notation, and requires less thought to really grok.

Nothing succeeds like the appearance of success. -- Christopher Lascl