A discovery leads to questions about whether the odds of people sharing genetic profiles are sometimes higher than portrayed. Calling the finding meaningless, the FBI has sought to block such inquiry.
posted on Jul 20, 2008 - View this thread

On May 13, security advisories published by Debian and Ubuntu revealed that, for over a year, their OpenSSL libraries have had a major flaw in their CSPRNG, which is used by key generation functions in many widely-used applications, which caused the "random" numbers produced to be extremely predictable. [lolcat summary]
posted on May 16, 2008 - View this thread

The Monty Hall Problem has struck again, and this time it’s not merely embarrassing mathematicians. If the calculations of a Yale economist are correct, there’s a sneaky logical fallacy in some of the most famous experiments in psychology." The NY Times' John Tierney reports on new research into cognitive dissonance as examined through the famous Monty Hall Problem. [A previous MetaFilter thread about the Monty Hall Problem: Let's Make A Deal!]
posted on Apr 8, 2008 - View this thread

Poker hand simulator. Get a feel for the odds before you bet the farm.
posted on Feb 16, 2008 - View this thread

If you need a foolproof way to decide whether to kill someone or are simply curious as to whether probability is still operating as a factor in your existence (and find yourself out of change but near a computer with an internet connection), you can just use flip a coin.
posted on Dec 13, 2007 - View this thread

Interactive mathematics miscellany and puzzles, including 75 proofs of the Pythagorean Theorem, an interactive column using Java applets, and eye-opening demonstrations. (Actually, much more.)
posted on Dec 1, 2007 - View this thread

How many group photographs do you have to take to get one in which nobody is blinking? Nic Svenson and Dr Piers Barnes work it out.
posted on May 22, 2006 - View this thread

We've talked about quantum computation a few times before, but how much do we really know? Metafilter, instruct thyself. Don't forget to learn some advanced probability and computational complexity (Scott Aaronson has more). Whoa, that's a lot o' learning, so let's so check out the much easier, and much cooler "sleeping puppy" experiment. I can only dream that will help break quantum mechanics' association with animal abuse. Then, there's the Free Will Theorem that just came out (some discussion on it) and another paper with a new look at an old problem. The latter describes another way of solving ye olde, super importanto Einstein-Podolsky-Rosen paradox using the relational interpretation of quantum mechanics (lots of discussion running around). Whew. We don't need the crackpot ramblings of What the #$*! Do We Know? when we've got real physics to keep us up at night. So, who wants to become a physicist? (t'Hooft has some thoughts for those who want to go theoretical.)
posted on Apr 25, 2006 - View this thread

Experts can suck at predicting the future. Their intuitive sense of probability is no more developed than lay-people's. A classic experiment is to present two indistinguishable choices are presented, but with unequal probability of reward. Humans look for complex patterns, which don't exist, and preform quite poorly. Rats quickly recognize the choice with higher probability, and preform optimally.
posted on Dec 11, 2005 - View this thread

Everybody's an expert, but does expertise promote better predictions?
posted on Dec 1, 2005 - View this thread

Know less than nothing!? What could negative knowledge possibly mean? In short, after I tell you negative information, you will know less... "In this week's issue of Nature, however, Michal Horodecki and colleagues present a fresh approach to understanding quantum phenomena that cannot be grasped simply by considering their classical counterparts." [via slashdot :]
posted on Aug 8, 2005 - View this thread

Incredible -- but true coincidences are fascinating, and pleasing, to the psyche. I tend to agree with John Littlewood (a University of Cambridge mathematician) that "...in the course of any normal person's life, miracles happen at a rate of roughly one per month." In other words, statistically speaking, unusual coincidences are to be expected in a world teeming with billions of humans. Still, I find such coincidences stangely inspiring. More can be found here.
posted on Jul 7, 2005 - View this thread

The Logic of Diversity "A new book, The Wisdom of Crowds [..:] by The New Yorker columnist James Surowiecki, has recently popularized the idea that groups can, in some ways, be smarter than their members, which is superficially similar to Page's results. While Surowiecki gives many examples of what one might call collective cognition, where groups out-perform isolated individuals, he really has only one explanation for this phenomenon, based on one of his examples: jelly beans [...] averaging together many independent, unbiased guesses gives a result that is probably closer to the truth than any one guess. While true — it's the central limit theorem of statistics — it's far from being the only way in which diversity can be beneficial in problem solving." (Three-Toed Sloth)
posted on Jun 20, 2005 - View this thread

An Intuitive Explanation of Bayesian Reasoning. [Page contains Java]
posted on Jul 21, 2004 - View this thread

"We plan to put Beauty to sleep by chemical means, and then we’ll flip a fair coin. If the coin lands Heads, we will awaken Beauty on Monday afternoon and interview her. If it lands Tails, we will awaken her Monday afternoon, interview her, put her back to sleep, and then awaken her again on Tuesday afternoon and interview her again. The (each?) interview is to consist of the one question : what is your credence now for the proposition that our coin landed Heads? When awakened (and during the interview) Beauty will not be able to tell which day it is, nor will she remember whether she has been awakened before. She knows about the above details of our experiment. What credence should she state in answer to our question?"

In light of the recent thread on the Monty Hall problem, here's a probability puzzle that's even more mind-bending: the Sleeping Beauty problem. Some people say the answer is 1/2. Some people say the answer is 1/3. Some people say there is no answer. Papers have been written which can't resolve this one.
posted on Jul 21, 2004 - View this thread

A playable version of the Monty Hall problem. More information.
posted on Jul 20, 2004 - View this thread

Expect a miracle? Freeman Dyson on Littlewood's Law of Miracles: "...the total number of events that happen to us is about thirty thousand per day, or about a million per month. ...The chance of a miracle is about one per million events. Therefore we should expect about one miracle to happen, on the average, every month." From his review of book debunking the paranormal (whose views he isn't entirely willing to accept). Via Marginal Revolution
posted on Jul 14, 2004 - View this thread

The History of Probability - Excel Version Huge detailed timeline. [via Roll the Bones]
posted on Jul 11, 2004 - View this thread

What Are The Odds Against Hamlet? This wonderful piece, representative of British academia at its best, most tongue-in-cheek, inclusive and playful, still presents a problem which wasn't (probably can't be) solved. What are the odds that it could be taken seriously? Mathematicians and literary theorists enter at their peril. The rest of us can feel free!
posted on Feb 10, 2004 - View this thread