The moral objections to state-sponsored gambling were long ago swept away by courts and the apparently insatiable appetites of humans to wager on everything from horses and dogs to the whims of

random-number generators and bouncing pingpong balls.

Large-scale studies, which rely on high-speed

random-number generators and quicken the pace of volunteers' responses, seem to interfere with any psychokinetic effects, contends a group of psychokinesis researchers led by Dean Radin of the Institute of Noetic Sciences in Petaluma, Calif.

Using graph partitioning algorithms as an example, we demonstrate the often underestimated influence of these random-number generators on the result of the heuristic algorithms.

graph partitioning, heuristic algorithms, pseudo random-number generator

The random-number generator used for these tests was the randQ function from the Linux operating system.

These random-number generators are the algorithms of choice for applications such as encrypting credit card numbers in Internet transactions, for which unpredictability is of paramount importance.

One of the first of these physical random-number generators, called Random.

Faulty randomness Researchers provided new mathematical insight into why certain

random-number generators give wrong results in some computational experiments and simulations (www.

Ferrenberg, a computational physicist at the University of Georgia in Athens, and his co-workers have discovered that even "high-quality" random-number generators, which pass a battery of randomness tests, can yield incorrect results under certain circumstances.

As a last resort, Ferrenberg substituted different random-number generators and, to his surprise, found that he came much closer to the correct answer by using a linear congruential generator, which has known defects.

We've got a new situation in which conventional random-number generators just won't do," says George Marsaglia, a computer scientist and statistician at Florida State University in Tallahassee.

To better meet researchers' needs for lengthy strings of random numbers, Marsaglia and Florida State colleague Arif Zaman have developed a new class of computer-based random-number generators that produce "astonishingly long" sequences of random numbers.