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Comment Child Porn? (Score 1) 322

How long do you think it will be before some people start using these as a way to exchange child porn or some idiot thinks it would be funny to upload kiddie porn on all the USB sticks and the cops come in and shut the thing down?

Comment How Do Container Formats Work? (Score 1) 370

Alright, so despite doing a bit of reading on wikipedia I'm still pretty puzzled about exactly how container formats can work. Setting aside fancy features like user menus and things like chaptering it seems to me the primary purpose of a container format is to do two things.

1) Define a format to multiplex many different data streams, e.g., allow packets in the audio stream, video stream, subtitle data to be interleaved so the right data can be available when needed (putting all the video stream first then the audio stream would be a bad idea).

2) Provide synchronization information to let arbitrary video, audio, and subtitle formats coordinate their display.


Now 1 seems relatively straightforward. What confuses me is part 2. I mean if we were encoding video as a simple list of pictures and audio in pcm this would seem straightforward. Each packet encoding a video frame gets tagged with the frame number and each audio packet gets tagged with the frame number it should be played with.

However, how does this work given the fact that to display frame 10034 the video codec may need to use information from frame 10000 and similarly with the audio codec. So if I want to jump to frame 10034 the player needs to know to look back at the info for frame 10000. I mean I can think of various ways this might be done but they all would seem to require particular knowledge about how the individual streams work.

Could someone explain how these work or give me a pointer to a good explanation?


Comment Re:Flawed reasoning... (Score 2) 370

No, that's not true. Version 2 can simply define a new bit to indicate whether it's version 2 or later.

The real problem with this optimization is it's effect on later versions.

Say one eventually moves to version 12 and each version along the way defines it's own flag. That mean's you've used 12 bits and some very nasty decoding logic to indicate you are a version 12 format when you could have just reserved that one byte and used a case statement.

I mean the annoyance and difficulties created by using a next version flag (and the poor scaling behavior with higher version numbers) is a high price to pay to save a couple bytes in a multimedia codec.

Comment Re:Simple Winning Coalition (Score 1) 252

This is a contract with real money and the signatures are exchanging something of real value (their knowledge of the locations). It's a nice clean example of a contract, nothing weird or fishy. Moreover, contract law doesn't work like computer code. You simply include a clause requiring them to accurately disclose their knowledge about such and such a balloons location. If they know or have reason to suspect that it was a fake and they don't share they are violating the contract.

Comment The Ontological Argument (Score 1) 229

This (unfortunately) reminds me of the ontological argument and similar examples of bad reasoning that manage to avoid being laughed out of the room because they dress themselves in a false shroud of logical rigor.

One version of the ontological argument procedes by defining god to be the being which has the maximal amount of good qualities and continues from there. Now there are other problems with this argument but the giant gaping fallacy is that this simply isn't what people mean by god, a point that wouldn't be lost on anyone if you stripped off all the pretense of extreme rigor and just said, "Hey, something has to be the best thing."

I'm a big fan of using logic to demonstrate that our convential views are incoherent. Indeed, many of the issues mentioned here beg for such a treatment but disguising your hidden assumptions by pointless trapings of rigor (and I'm mathematical logician so I like rigor) gives those of us who actually want to reason about these situations a bad name and enlightens no one.

Grr...I mean just consider the free trade example. It sounds as if he is delibrately trying to slip past the reader that our goal is not to maximize the net inflow of 'dollars' to the US not to mention the existance of inefficent equilibriums. I mean I think nearly every protectionist sympathizer I've ever heard is being a total moron but you don't do anyone any favors by failing to mention that increased utility from trade may require transfer payments to compensate for the disparate impacts of trade. Maybe you oppose these on other grounds but if so you need to state the case. Ohh and BTW given the extremely strong evidence that many Chinese are eager to the point of breaking the law to get these 'sweatshop' jobs maybe the reviewer should try harder to believe that other things being equal they leave an individual better off on balance for taking the job. Perhaps by contemplating how much subsistance farming without modern medicine or convienences sucks.

And the god arguments repeat the same problems. Yes, it's interesting that adults treat religious beliefs differently than other beliefs but saying they don't believe in god doesn't accomplish anything. It just redescribes the situation confusingly. People still let their faith influence their attitudes on many policy questions (which they often also treat differently than beliefs about things they can affect). The ESP bit is even dumber. ESP, like most words, doesn't have a stipulative definition but rather is understood by something like prototype resembelance. It's like the word table, you know some things count and others (a bed) don't and evaluate weird new examples (three legged 2 foot radius stool) by their similarity. Besides, no one cares if 'ESP' exists, people care if people can read minds, remote view etc.. whatever you want to call it.

The only half-decent argument listed is the bit about free will. A better statement would be something like this:

Free will doesn't mean unpredictable/random. A person who heroicly rushes back into a burning building to save a trapped dog is exercising free will in that choice if anyone is even if they would make the same choice everytime you (exactly) replayed the situation. Indeed, if you rewound time and gave it another go and they acted differently that feels less like exercising free will. If free will makes sense then choices I make because of my charachter (how I see myself) surely count and not just choices which we might as well have left up to a coin toss. In other words it seems that what makes a choice free is that I get to select the outcome without outside dictation of the answer.

In other words for a choice to be free it must be possible for me to have acted differently, i.e., if I were inclined to select a different option then I could have done so. It doesn't require the absurd criterion that a free choice must be something that *I* don't determine, e.g., by being the sort of person who will race into burning houses. So now if we take the step of identifying ourselves with our brains we see there is no conflict. Had we wanted to make a different choice we would have had a different brain and hence would have acted differently. The key point is that determinism is really saying that *you*, embodied in a brain, in conjunction with the enviornment dictates the outcome while free will is saying that you make the choice. The only trouble arises because we aren't used to thinking of ourselves as brains so we imagine sortof floating outside the physical realm in which case if the physical world dictated the outcome we (not being part of that world) would have no choice in the matter. So once you are cool with yourself as a brain no problem.

Comment Simple Winning Coalition (Score 1) 252

Unless a technological approach using sattellites, automated analysis of flikr photos etc.. quickly wins out then presumably the ballons will end up being seen by some people aware of the contest. So suppose you have seen a balloon and wish to use that knowledge to claim part of the prize. What do you do?

Well what you want to do is find a group of other people who have located the other balloons and agree to pool your info in exchange for shares of the prize. Importantly nothing in the rules prevents you from drawing up legal contracts with other participants and if you are clever you might even be able to make delibrately feeding you false information into criminal fraud. So it seems straightforward to ensure there are big incentives to only agree to join such a coalition if you do indeed have valid data. Moreover, your claimed data can be verified relatively quickly for low cost by paying close friends and associates who live nearby to go out and check.

In short it seems to me the optimal strategy is simply to hope you stumble upon a balloon and then creating a legally binding contract with others who claim to have complimentary information.

Comment There Is No News Crisis (Score 5, Insightful) 323

There is a crisis for journalists as a result of the sudden crash in their industry but that crash isn't the result of some horrible failure of the market for journalism. Just the opposite. The newspaper industry has hit bottom because the internet has made the buisness of reporting so much more efficient. I mean just thinking about the huge number of daily papers across the states carrying the same national and international news on print is enough to make one sick at the waste. Not only does it cost a great deal to publish a print daily but each of these dailies employs editors and layout people to format the same news availible anywhere in their particular style. Many of them even insist on hiring their own reporters even when it's obviously duplicated effort (say reviewing national movies/TV shows).

Once competition drives most local papers to focus on local intersts and everyone to publish online it will free up a quite substantial amount of money for real reporting. Though actually a lot of what journalists call real reporting is duplicated effort for the sake of status. I mean does it really help the public understand what's going on better to have 40+ journalists at the white house press briefings and who knows how much AV equitment? If they just sent over a single camera crew and agreed on a way to pick questions there would be no harm to the quality of reporting. Much of this is just done because historically that behavior signaled prestige and seriousness in the news industry.

I don't think the newspapers are doing anything wrong. But when technology lets you accomplish the same job with disruptively less total effort (delivering news to the nation) many people are going to lose their jobs and most of the companies in that industry will go out of buisness. I feel sorry for the people with careers in the industry but I think there is every reason to believe that after things settle down there will be just as much investigative reporting and important journalism. There will just be less redundancy and a more efficient use of reporting resources.

Comment 128 bit addressing (Score 1) 581

While obviously unnecessery from an addressing point of view it does offer some interesting advantages in terms of security. In particular rather than bothering with expensive hardware memory protection one can simply rely on the extreme sparseness of memory usage to provide process least if you do other things right (randomize layouts etc..)

Comment Fucking Dumb Question (Score 3, Insightful) 404

Of course most people say they don't want targeted ads. I mean it's like asking "Would you like your taxes to be raised." Of course people say no because other things being equal people would prefer zero taxes and almost no ads. Of course if you asked whether you would prefer the government increase the gas tax or income tax, or whether a tax hike would be a worthwhile price to pay for universal health care you would get very different answers.

In this sense ads are quite similar to taxes. We would prefer to get our government services for free and our media without any ads but since that's not possible question that matters is what tradeoffs you would like to make. I suspect if you asked people whether they would prefer to get tageted advertisements, a substantially larger number of untargeted ads or no longer get free webmail and the like I think you'll find many people take the first option.

Also it's well documented that people seem to only really care about privacy/psuedo-anonymity/targeting when someone asks these kind of ominously phrased questions. I mean all the 'experts' go around saying vague ominous sounding things about losing privacy/etc so you ask people a question about privacy/etc.. and they think, "Hmm, I don't really understand what all the fuss is but it sounds kinda ominous and know I probably should be more responsible and worry about these issues." So your never finding out how much people actually mind losing their privacy and the like, they may not even notice. All you're really measuring is how much vague scary statements make people think they should worry about something.

Ohh, and the fact that so many experts seem to take these concerns seriously is no more useful. If you dismiss a danger like that rather than looking thoughtful and concerned you appear less serious. I mean it's the same reason doctors and other medical experts in the mainstream media never get up and say, "Pshhaw, marijuanna use by teens isn't anything to worry about," despite having uncontrovertable data that it is way less risky that many other accepted activities. Once society views something as posing a risk and takes it to be a serious matter then any role models who refuse to treat it as a matter of serious concern are considered irresponsible and blamed for any harm that might have been avoided by being overly cautious.

Comment Thoughts (Score 1) 157

Some quick observations:

  • First judges have generally applied balancing tests between free speech and publicity rights so this means that if this result stands EA would probably still have to shell out to Madden for Madden Football but if you appear as simply a name, likeness and stats on a sports team you probably won't be able to win a lawsuit based on any kind of publicity right. In other words being depicted in the game and being plastered all over the box to move more copies are different things.
  • Surely this is a minimal requirement to have anything like freedom of expression for video games that public figures can be depicted as inhabiting historical/counterfactual situations without requiring any kind of licensce, permission or payment. Otherwise video games would be unable to comment on any issues of public concern or historical interest unless they made all the participants happy with their depiction. If you make an LAPD game you shouldn't need to get OJ's permission to help pursue him in the "high speed" chase.
  • More broadly I feel that any kind of publicity right for public figures going beyond false endorsement style laws is incompatible with the first ammendment. If I want to write a novel depicting Bill Clinton's secret life as a butt kicking comando only good taste and not the law should stop me. Video games deserve no less protection and taken together these two observations essentially eviscerate publicity rights.

To put the point another way: Just because you participated in historical events doesn't give you the right to influence the (fictional) depiction of these events. If you don't like your likeness appearing in the media then don't let yourself become a public figure.

Comment Re:Good idea, or overstepping (Score 1) 776

Yah, and people like you forget that the amendments were only restrictions on federal power when the constitution was adopted and given that taxes on sweets are likely to be imposed by the states it's unclear if the 9th ammendment is even relevant to the discussion.

The supreme court has determined that the 14th amendment incorporates much (but not all) of the bill or rights against the states but it's not clear that incorporation even makes sense for the 9th amendment. I mean the 9th merely says that other rights are reserved to the states or to the people but doesn't specify which so even if incorporated there isn't any state action that could facially violate the literal meaning of the 9th.

Comment Lies and Bullshit (Score 1) 776

I have no problem with governmental tweaks to economic incentives to improve social welfare. I'm a strong supporter of a carbon tax for this reason and there are probably a number of consumer products that would be beneficial to tax or regulate in some way because of true economic failure*.

However, these attempts to justify regulations of smoking and foods by reference to market failure drive me nuts as they are usually at best total bullshit and at worst outright lies. For instance it's simply not true that smokers impose higher health care costs on society. Indeed, as the congressional budget office noted when they considered this issue, the savings that result from early deaths by way of lower medicare and social security costs may actually exceed the extra health care resources consumed by smokers. As the economist noted once you factor in the cigarette taxes smoking is a a clear net positive for government finances.

So do people who consume soda and other sweets impose additional costs on society? I sure as hell don't know but you can't just assume they do because it's unhealthy. Sure, your average voter might be excused for not considering the potential savings that may counterbalance the costs but it's inexcusable for academics publishing in the New England Journal of Medicine. Well then what about advertisements. Do they encourage people to purchase these products? Almost certainly. Does this mean they indicate a market failure? Surely not. Maybe we would be under consuming these products relative to the utility they offer without these ads. Indeed, it's quite possibly the case that the very existence of the ads makes consuming these products more enjoyable. Lastly the bit about discounting the future is completely absurd. No only is discounting not itself irrational but even if we charitably take the argument to be addressed at hyperbolic discounting it's no more applicable to soda than to the decision to drop a dollar into the red cross bucket at Christmas.

Maybe it really does make sense to tax soda but don't adopt a flimsy pretense of objective argument to excuse penalizing behaviors you already disapprove of. I mean if these authors were truly objective they would insist on better arguments before leaping to this kind of conclusion and consider the potential harms that embarking on this kind of policy might bring.

Comment Re:Does Not Address the Fermi Paradox (Score 1) 642

No, I'm claiming there are general considerations which mean the percentage of species who emit such detectable signals for a long period of time is quite small.

In particular there are general pressures toward more efficient encoding and transmission which make signals harder for us to detect. Also I argued there are systematic pressures (desire for more computational resources) which push the interest of such civilizations away from low energy regions like ours.

Comment Simulations or Reality (Score 1) 642

To make the same point differently why wouldn't advanced alien civilizations just stay home and play in their virtual worlds rather than go colonize the galaxy and separate themselves from their community. I mean if your advanced enough to engage in serious galactic colonization you are advanced enough that you don't need to worry about natural disasters destroying your residence.

Hell, even if the aliens are curious about what might have evolved in other solar systems it might be easier to let perfectly described solar systems evolve in simulation than to actually go visit them. They can see interesting creatures evolve just as easily in simulation as in reality.

Comment Advanced Alien Behavior (Score 5, Insightful) 642

It's always seemed to me that the major hole in the Fermi paradox is the assumption that technologically advanced alien civilizations would be emitting signals we would recognize.

I mean it's kinda hubristic to assume they want to talk to us. After all we may study chimps but we don't go out of our way to show up in the middle of nowhere to say hello. That leaves the question of why we don't detect communication leakage, e.g., radio signals they use for communication. However, not only is it not obvious that they would use radio to communicate, or that we could recognize such signals, but it's not even obvious they would bother to colonize the galaxy or communicate between planets.

For example suppose that sufficiently advanced civilizations transform themselves into some form of 'computational' life. Such a civilization couldn't care less about planents or minerals. What would matter to them is processing power per unit volume. It would therefore make sense for such civilizations to seek out the regions with the highest energy density that would allow them to access the most processing power. Rather than racing around the galaxy in starships and living at the same crawlingly slow pace we do such civilizations might exist entirely in the high energy regions in neutron stars or around black holes. So why would we expect to meet them. Hell, even if they care about meeting aliens too the aliens they care about are probably the ones who already inhabit similar regions.

Even if we think it's reasonable to assume aliens are sending messages all over the galaxy the more efficiently such messages are encoded the harder it will be for us to identify them. The closer such transmissions approach the Shannon limit for the communications channel the harder they would be to distinguish from random noise (and we don't know enough to rule out a natural source). Also the more effective use they made of their communications equipment the less stray signal that would wash the earth, even if it was encoded in radio instead of neutrinos or something weird (some papers have suggested neutrinos would be a better long range communication method).

The point is that even if we take for granted that there a fucktons of advanced alien civilizations around it just doesn't follow that we should be able to detect them.

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