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Comment: Re:Cause meet Effect. (Score 1) 47

by PacoSuarez (#49073451) Attached to: When Chess Players Blunder

Although ultimately you are right, there is a useful probabilistic approach to this besides considering the theoretical value of a position. Since chess is very far from being solved, you don't really know the theoretical value of very many positions. However, you can make models for the probability of the outcome from a position (a choice of an engine is such a model). A blunder is then a move that reduces the expected score for the player that made it, by some amount.

And as others have said, he should have used Stockfish.

Comment: Re:Consciousness versus Intelligence (Score 1) 455

This position seems to be popular among people that don't know the first thing about AI. So let me explain the situation from a point of view familiar to AI practitioners: A rational agent is one that acts as if it were maximizing the expected value of some utility function. That, in a nutshell, is the core of making decisions under uncertainty, and the basic recipe for a large part of AI. As part of the design of a utility-centered AI system, you define the utility function, which is precisely how you would tell the machine what to want. None of this "boggles the mind". It is almost trivial, actually. The difficult parts are perception, how to model future events to evaluate the expected value of the utility function in different scenarios, etc.

Comment: Re:Phooey. They Can Still Kill Us All (Score 1) 455

Don't worry. It is using a non-standard prototype for `main', and it forgot a few semicolons. It will stop working the next time the compiler is updated. Who knew that some obscure idiosyncrasies of the C programming language would save humanity? :)

Comment: Re:Here comes a Karma hit.... (Score 1) 107

I was programming at her age (BASIC on some 8-bit computer), and I turned out OK. My parents weren't very happy that I spent many hours a day in front of the computer, but that's what allowed me to have a great job as an adult.

I would just let the girl do whatever she is interested in.

Comment: Re:I'm not a scientist... (Score 4, Funny) 99

by PacoSuarez (#48328077) Attached to: French Health Watchdog: 3D Viewing May Damage Eyesight In Children

According to Anses, the process of assimilating a three-dimensional effect requires the eyes to look at images in two different places at the same time before the brain translates it as one image.

Isn't that how normal vision works anyway?

That's why France doesn't allow children under the age of six to open both eyes at the same time.

Comment: A much simpler method (Score 5, Interesting) 93

by PacoSuarez (#48080117) Attached to: Fixing Steam's User Rating Charts

If the only two choices are positive/negative (or thumbs up/thumbs down or some other equivalent 0/1 scheme), here's a formula that should work fairly well:

(n_positive + 1) / (n_positive + n_negative + 2)

So a single positive review gives you a score of .6667, and a single negative review gives you .3333. For large numbers of reviews, the score quickly converges to the actual fraction. If you don't have any reviews, you are at .5000.

The mathematical justification for this formula is that if you try to use a Bayesian approach to estimating the true probability of getting a positive review, and you start with a flat prior, this formula gives you the average of the posterior probability after observing the given number of positive and negative reviews. The full posterior distribution is a beta distribution with parameters alpha=n_positive+1 and beta=n_negative+1.

This formula is often used when applying Monte Carlo techniques to the game of go. I believe a lot of programmers simply start the counters of wins and losses at 1 to avoid corner cases (like division by 0), and they accidentally use the correct formula.

Comment: Re:Question... -- ? (Score 1) 215

by PacoSuarez (#47332961) Attached to: Exploiting Wildcards On Linux/Unix

While that is indeed the solution, it is also true that it is too easy to forget. Perhaps one could modify all commands to require the use of the "--" separator, or to warn if it's not present, at least if some environment variable is set. That could be very helpful for people trying to write more secure code.

Comment: Re:Good! (Score 1) 279

by PacoSuarez (#46498839) Attached to: The Billionaires Privatizing American Science

Please compare the supermarket shelves in the USA with those in Venezuela or North Korea and then come back here and tell me why big government controlling the means and distribution of production is a good idea, compared to the free market, with people providing each other with services in return for a token of exchange (currency).

I'm not saying that there isn't an element of truth in what you are saying, but you have to pick comparable countries or the comparison will mean nothing. So looking at North Korea versus South Korea is fine, as is comparing Venezuela to Colombia, or Cuba to Dominican Republic. If you want to compare the U.S. to anyone, perhaps Sweden would do. But Sweden is pretty darn nice. :)

Comment: Re:15 years? Try 200. (Score 1) 294

by PacoSuarez (#46432839) Attached to: Why Robots Will Not Be Smarter Than Humans By 2029

This idea that in order to achieve intelligence you need to understand how the brain works is preposterous.

We don't understand how grandmasters play chess, and yet we can build machines that play chess better than any grandmaster. The same thing will happen with more and more skills, and we'll get to a point where it will be clear that machines are more intelligent than humans.

2029 sounds optimistic to me, but the arguments in TFA are very weak:
* "What exactly does as-smart-as-humans mean?" It means "as good as humans at most tasks". The precise definitions won't matter when you actually see the machine in action.
* "Human intelligence is embodied." But artificial intelligence need not be embodied. If we can make a machine as smart as Stephen Hawking, I think we have done OK. I don't think his embodiment is a key part of his intelligence.
* "As-smart-as-humans probably doesn’t mean as-smart-as newborn babies, or even two year old infants." Of course not, but there is no reason a machine would have to learn at the same pace we do, or from the same sources, or in a similar fashion. Going back to the computer chess analogy, a grandmaster requires years of experience to learn how to play well, while a program can parse a large database of games and learn from them in a matter of hours or days.
* "Moore’s Law will not help." This is retarded. The paragraph goes on to acknowledge that it will help, but computer power is not the whole story. Of course it's not the whole story! But it will certainly help.
* "The hard problem of learning and the even harder problem of consciousness." Machine Learning is a very active discipline, with many recent successes. I don't think learning is a serious obstacle. I don't see a problem of consciousness anywhere. "Consciousness" sounds like a new name for "the soul" to me: It's likely to be an attribute that we assign to people as part of the theory of mind, not an actual thing we need to produce and insert into our machines. In any case, it has very little to do with intelligence.

It won't matter if we know what makes humans intelligent, or what intelligence is, or what consciousness is: The proof will be in the pudding. When you see machines that surpasses humans at most tasks we think of as requiring intelligence, we'll have intelligent machines. And philosophers can continue to argue about definitions all they want.

Comment: Re:Standard deviation BAD, but mean GOOD? (Score 1) 312

by PacoSuarez (#45982059) Attached to: Why Standard Deviation Should Be Retired From Scientific Use

I am not sure how I feel about that measure. If we were to use the median absolute error and try to be consistent, we would have to use as the central measure whatever minimizes the median absolute error. That would be a point somewhere between the 25th and 75th percentile, in the "flatter" part of the distribution, in some sense. I don't know if that central measure has a name, but I suspect it's not very relevant in practice.

Comment: Standard deviation BAD, but mean GOOD? (Score 4, Interesting) 312

by PacoSuarez (#45970275) Attached to: Why Standard Deviation Should Be Retired From Scientific Use

Perhaps non-mathematicians don't have a problem with this, but it rubs me the wrong way.

What makes the mean an interesting quantity is that it is the constant that best approximates the data, where the measure of goodness of the approximation is precisely the way I like it: As the sum of the squares of the differences.

I understand that not everybody is an "L2" kind of guy, like I am. "L1" people prefer to measure the distance between things as the sum of the absolute values of the differences. But in that case, what makes the mean important? The constant that minimizes the sum of absolute values of the differences is the median, not the mean.

So you either use mean and standard deviation, or you use median and mean absolute deviation. But this notion of measuring mean absolute deviation from the mean is strange.

Anyway, his proposal is preposterous: I use the standard deviation daily and I don't care if others lack the sophistication to understand what it means.

Comment: Re:Totally flawed model (Score 1) 169

by PacoSuarez (#45968329) Attached to: Why Transitivity Violations Can Be Rational

They don't claim to have a realistic model of the situation: They showed a very simple model in which the rational behavior contains an apparent violation of transitivity. And they didn't need to introduce a variety of nutrients to obtain it. This makes their model better, in the sense that it is simpler.

[Sorry, I posted as AC earlier.]

... though his invention worked superbly -- his theory was a crock of sewage from beginning to end. -- Vernor Vinge, "The Peace War"

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