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Comment Re:Infinity (Score 1) 183

Not every infinitely long random number contains every possible pattern. Consider an infinitely long sequence of digits. Now drop all '1's from the sequence. You still have an infinitely long series of random digits, in that knowing previous digits doesn't help you predict future digits. However, this infinite random sequence does not contain every possible pattern.

Whether this applies to pi or not, I have no idea.

The correct formulation of "every possible pattern" is that given an infinite sequence of letters (or digits) from an alphabet A, where every letter is chosen uniformly, the probability that a given pattern of finite length will appear somewhere is 1.

So there're two problems with your example. First of all, after removing the '1's, the digits in the resulting sequence aren't uniformly distributed. Secondly, just because the probability of a pattern appearing is one, that doesn't necessarily mean that the pattern will appear. For example, it's possible that the random sequence consists of only one digit. Such a sequence clearly doesn't contain every pattern. But the probability of generating such a sequence is zero. Similarly, it's certainly possible that the infinite sequence doesn't contain any ones, but the probability of that happening is zero.

Comment Re:I am not surpised (Score 4, Insightful) 244

Actually, microeconomics theory shows that the prices would drop and the corporations would make a higher profit. Some companies will be willing to slightly lower the prices. This will pressure other companies to lower prices until an equilibrium is reached. Eventually, the abolished taxes will go partly to the consumers and partly to the producers.

Submission + - Popsicle stick turing machine (

daniel_i_l writes: This link shows a turing machine made out of popsicle sticks and polygal. The only electric parts are regular mechanical switches, a dc moter, and two solenoids. The machine moves along a track and moves lego blocks back and forth which act as the tape. The mechanics of the machine are explained in the video.

Comment Re:Unacceptable false positive rate (Score 1) 190

MRIs are expensive, and autism-like behavior is obvious enough that you can narrow down the group of people you're going to test significiantly before you start testing.

In the case of autism, the earlier you get a diagnosis the more effective the treatment will be. So waiting until the child starts showing symptoms isn't ideal. It's better to have a way of testing for autism while the child is still under a year old. That's why it's important to have physiological tests, as opposed waiting for the parents to notice eye contact or social problems.

Comment Re:Don't target cars (Score 1) 1139

There's a big difference between a plane and a train. With a plane, it's easy to inflict massive damage with relatively small weapons. This is because you're dealing with an aluminum tube packed with people flying through the sky. If it get's diverted the smallest amount from it's path, or sustains minor physical damage, then a large percentage of the people inside will die. The 9/11 terrorists brought down the twin towers armed with trivial weapons such as knives. In addition, a plane is an isolated environment, so once a handful of terrorists take control, there isn't much that the entire US armed forces can do to stop them, short of taking down the plane.

But with a train that's all different. The train is on the ground so it's easy for a helicopter to catch up with it, drop $SPECIAL_FORCE on the the roof, and take back the train. And even if a terrorist does manage to detonate a bomb on the train, it will probably only kill people in the same car.

So I think that there's more reason to be paranoid of terrorists on planes.


Video Quality Matters Less If You Enjoy the Show 366

An anonymous reader writes "Rice University researchers say new studies show that if you like what you're watching, you're less likely to notice the difference in video quality of the TV show, Internet video or mobile movie clip, putting a lie to some of the more extravagant marketing claims of electronics manufacturers. 'If you're at home watching and enjoying a movie, we found that you're probably not going to notice or even concern yourself with how many pixels the video is or if the data is being compressed,' said the lead researcher. 'This strong relationship holds across a wide range of encoding levels and movie content when that content is viewed under longer and more naturalistic viewing conditions.'"
Input Devices

Textured Tactile Touchscreens 99

HizookRobotics writes "A new covering developed by Senseg and Toshiba Information Systems gives touchpads, LCDs, and other curved surfaces (eg. cellphones) programmable texture using a high-resolution electrotactile array — a grid of electrodes that excite nerves in the skin with small pulses of current to trick the body into perceiving texture, pressure, or pin-pricks depending on the current amplitude and electrode resolution. The new covering has many potential applications: interactive gaming, touchscreens with texture, robot interfaces, etc."

Comment Re:variable names and data structures. (Score 1) 578

This does arouse suspicion. even if you forget the variable names for a moment, any pattern like bool,real,real, *real, int, *char,*char,*bool,.... that is identical between two structs would be an improbable occurence. and when you see it in back to back structs it becomes nearly impossible to happen by chance.

Actually, the order of declarations in a struct is far from random. Even without getting into specifications and compatibility, there're multiple performance issues (such as padding) that are directly related to the exact order of the variable declarations.

Comment This site describes the machine (Score 5, Informative) 168

Here: The Science Page I found the following: "A machine which said 'COFFEE' which was located in the center hall. The machine was built from discrete components and had a series of coils and capacitors for filters and oscillators. Lamps lit up the letters "C", "O", "FF" and "EE" as the machine spoke. Visitors could vary parameters using analog pots to make the word sound different." So maybe Mark Csele knows.

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