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Submission + - The Game Theory of Life (

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.

Submission + - Project Euler shut down indefinitely (

Big_Oh 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.

Submission + - NADA Is Terrified Of Tesla

cartechboy 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

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

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

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."

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