You don't save them for the same reason that you don't necessarily save the state of the simulation after every state change. You're generating a lot of these things, conceivably billions and billions or more. Even if you do save that kind of data for the short term--be it the pseudorandom sequence or state changes or both--you may want to eventually delete it while still having the option of re-creating it at a later date. With a reproducible pseudo-random generator, you can do this by saving only the parameter settings and the seed value.
For scientific research, there's a very good reason to use pseudo-random numbers: reproducibility.
If you're analyzing a stochastic model, you want to be able to generate lots of runs with different random sequences and gather statistics from the ensemble. But if you see interesting behavior in a particular run and want to take a closer look, you want to be able to go back and run it again, exactly as it happened the first time. In this case, you don't want real randomness, you want pseudo-randomness with good statistical properties. I'm currently checking through my code to make sure you can do just that when using this tool.
The intelligent design "argument," by the way, is simply a new realization of the age-old argument that Richard Dawkins calls the "argument from personal incredulity." (If you haven't, go read Dawkins' The Blind Watchmaker.) The argument goes like this: an ID proponent might look at a complex biological systems such as the bacterial flagellum and say, "my, that's really complex, isn't it? I can't possibly see how any of those component parts is any good on its own. I can't imagine that such a structure possibly could have evolved through gradual change and recombination of preexisting structures." In other words, ID proponents give up and assume, quite literally, a deus ex machina.
The alternate approach is to actually attempt an explanation. While it's true that biologists haven't come up with compelling evolutionary explanations for every single biological phenomenon observed, the theory of modification and selection is the best one we have to explain biological complexity in general, and I expect that its descriptive power will only grow as we learn more about the details of life. And it's certainly much better than throwing your hands in the air and saying, "that's too complex! There must be a go^H^H^Hn intelligent designer! Hallelujah!"
You're exactly right. As others have pointed out here, however, it's likely that the terms of the agreements with the big 4 require that all music sold on the store be protected with FairPlay. Still, I think this open letter may begin the process to a DRM-free world.
It was my fear—and probably the fear of many people here—that Apple's motivation for using FairPlay was twofold: one, that the music companies wanted it; and two, that they wanted to help strengthen the iTunes/iPod tie-in. Turns out, if Jobs is being fully genuine, that only the first reason is true. Which is a wonderful thing, because Apple is on the side of those who really get the future of music: savvy consumers and independent artists.
This calls for a grassroots effort to get Apple to alter its contracts with the music companies to allow copyright holders to specify that their music be sold without DRM. If enough consumers and artists start shouting loud enough, this just might happen. If Apple's hands are tied because of contracts, I seriously wonder if a lawsuit by an artist against Apple could force Apple's (willing) hand.
Ideally, of course, the music companies will just wise up, realize their old business model cannot be preserved with encryption technology, and give up the gun. But I'm not holding my breath.
Are there any existing activism efforts by artists to get Apple to sell DRM-free music on iTunes? If there isn't one, consider this post a statement of intent to start such an effort. I happen to be in a band that just released a a cd under a Creative Commons license. If nobody else is on the ball, I will contact people at Apple, start an open letter/petition, and hopefully get this first step—letting copyright holders decide if they want DRM or not—going.
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You don't save them for the same reason that you don't necessarily save the state of the simulation after every state change. You're generating a lot of these things, conceivably billions and billions or more. Even if you do save that kind of data for the short term--be it the pseudorandom sequence or state changes or both--you may want to eventually delete it while still having the option of re-creating it at a later date. With a reproducible pseudo-random generator, you can do this by saving only the parameter settings and the seed value.
For scientific research, there's a very good reason to use pseudo-random numbers: reproducibility.
If you're analyzing a stochastic model, you want to be able to generate lots of runs with different random sequences and gather statistics from the ensemble. But if you see interesting behavior in a particular run and want to take a closer look, you want to be able to go back and run it again, exactly as it happened the first time. In this case, you don't want real randomness, you want pseudo-randomness with good statistical properties. I'm currently checking through my code to make sure you can do just that when using this tool.
Here's the original paper.
The intelligent design "argument," by the way, is simply a new realization of the age-old argument that Richard Dawkins calls the "argument from personal incredulity." (If you haven't, go read Dawkins' The Blind Watchmaker.) The argument goes like this: an ID proponent might look at a complex biological systems such as the bacterial flagellum and say, "my, that's really complex, isn't it? I can't possibly see how any of those component parts is any good on its own. I can't imagine that such a structure possibly could have evolved through gradual change and recombination of preexisting structures." In other words, ID proponents give up and assume, quite literally, a deus ex machina.
The alternate approach is to actually attempt an explanation. While it's true that biologists haven't come up with compelling evolutionary explanations for every single biological phenomenon observed, the theory of modification and selection is the best one we have to explain biological complexity in general, and I expect that its descriptive power will only grow as we learn more about the details of life. And it's certainly much better than throwing your hands in the air and saying, "that's too complex! There must be a go^H^H^Hn intelligent designer! Hallelujah!"
It's worth noting that one of the founders of Greenpeace has since come out in support of nuclear power.
You're exactly right. As others have pointed out here, however, it's likely that the terms of the agreements with the big 4 require that all music sold on the store be protected with FairPlay. Still, I think this open letter may begin the process to a DRM-free world.
It was my fear—and probably the fear of many people here—that Apple's motivation for using FairPlay was twofold: one, that the music companies wanted it; and two, that they wanted to help strengthen the iTunes/iPod tie-in. Turns out, if Jobs is being fully genuine, that only the first reason is true. Which is a wonderful thing, because Apple is on the side of those who really get the future of music: savvy consumers and independent artists.
This calls for a grassroots effort to get Apple to alter its contracts with the music companies to allow copyright holders to specify that their music be sold without DRM. If enough consumers and artists start shouting loud enough, this just might happen. If Apple's hands are tied because of contracts, I seriously wonder if a lawsuit by an artist against Apple could force Apple's (willing) hand.
Ideally, of course, the music companies will just wise up, realize their old business model cannot be preserved with encryption technology, and give up the gun. But I'm not holding my breath.
Are there any existing activism efforts by artists to get Apple to sell DRM-free music on iTunes? If there isn't one, consider this post a statement of intent to start such an effort. I happen to be in a band that just released a a cd under a Creative Commons license. If nobody else is on the ball, I will contact people at Apple, start an open letter/petition, and hopefully get this first step—letting copyright holders decide if they want DRM or not—going.