E-mail This Article To A Friend:

do the mathDo the MathA mathematician's guide to the news.4NA=1154&NC=1269&DI=4098&PS=58325&PI=7315mathfalsefalsespacernotembeddeddo the mathGuilt by CalculationJordan EllenbergIt takes more than an Excel sheet to prove the Iranian election was fixed.noGuilt by CalculationHunting for statistical fraud in Iran's elections.noWere Iran's election numbers too good to be true? That's the question that the blog Tehran Bureau raised hours after Friday's election, when it noted a strange trend in the government's electoral data: Each time a new vote total was released, President Mahmoud Ahmadinejad had won a nearly identical percentage, around 67 percent. As more results rolled in, his tally climbed in linear lock step.truenotochyperlinkno2009617104658AMWednesdayJunJune106/17/2009 2:46:58 PM6338083241800000002009617104658AMWednesdayJunJune106/17/2009 2:46:58 PM633808324180000000do the mathWe're Down $700 Billion. Let's Go Double or Nothing!Jordan EllenbergHow the financial markets fell for a 400-year-old sucker bet.noWe're Down $700 Billion. Let's Go Double or Nothing!How the financial markets fell for the martingale, a 400-year-old sucker bet.noHere's how to make money flipping a coin. Bet 100 bucks on heads. If you win, you walk away $100 richer. If you lose, no problem; on the next flip, bet $200 on heads, and if you win this time, take your $100 profit and quit. If you lose, you're down $300 on the day; so you double down again and bet $400. The coin can't come up tails forever! Eventually, you've got to win your $100 back.truenotochyperlinkno200810212011PMThursdayOctOctober1310/2/2008 5:20:11 PM633585504110000000200810212011PMThursdayOctOctober1310/2/2008 5:20:11 PM633585504110000000do the mathMean GirlsJordan EllenbergThe New York Times slips up on sexual math.noMean GirlsThe New York Times slips up on sexual math.noIn Sunday's New York Times, science writer Gina Kolata took on studies suggesting that men tend to have more sexual partners than women do. This CDC study, for one, shows that American men between the ages of 20 and 59 report accumulating a median of seven female bedmates, while for women the corresponding figure is just four. The problem, Kolata writes, is that these numbers present a mathematical contradiction. "It is logically impossible for heterosexual men to have more partners on average than heterosexual women," she explains. "Those survey results cannot be correct." Kolata even quotes a theorem to this effect, backed up by mathematician David Gale of Berkeley: The average number of partners has to be the same for men and women.truenotochyperlinkno200781360904PMMondayAugAugust188/13/2007 10:09:04 PM633226253440000000200781360904PMMondayAugAugust188/13/2007 10:09:04 PM633226253440000000do the mathWill the Democrats Flip the House?Jordan EllenbergSlate's mathematician on the odds of a Democratic victory.noWill the Democrats Flip the House?Slate's mathematician on the odds the Democrats will flip the House.noIt's an anxious season for the GOP. With midterm elections eight weeks away, two dozen Republican-held seats in the House of Representatives are too close to call. Republican strategists interviewed by the Washington Post suggested that the Democrats had a 75 percent or even 90 percent chance of seizing control. Charlie Cook, a respected nonpartisan analyst, told the New York Times, "If nothing changes, I think the House will turn."truenotochyperlinkno200691911753PMTuesdaySepSeptember139/19/2006 5:17:53 PM632942686730000000200691911753PMTuesdaySepSeptember139/19/2006 5:17:53 PM632942686730000000do the mathWho Cares About Poincaré?Jordan EllenbergMillion-dollar math problem solved. So what?noWho Cares About Poincaré?Does the proof of the Poincaré conjecture matter?noThe New York Times recently reported that reclusive Russian geometer Grigory Perelman has apparently proved the century-old Poincaré conjecture. The Times calls Poincaré "a landmark not just of mathematics, but of human thought." But just why it's so significant is left a bit hazy. Big mathematical advances often generate the same kind of lofty but content-free rhetoric found in political speeches about "the family." Like the family, math is a subject everyone agrees is very important without being able to specify exactly why.truenotochyperlinkno2006818115905AMFridayAugAugust118/18/2006 3:59:05 PM6329149914500000002006818115905AMFridayAugAugust118/18/2006 3:59:05 PM632914991450000000200311442836PMTuesdayJanJanuary161/14/2003 9:28:36 PM631781585160000000200311442836PMTuesdayJanJanuary161/14/2003 9:28:36 PM631781585160000000falsetruetruetruetruetruetrue20011018111443PMThursdayOctOctober2310/19/2001 3:14:43 AM6313904368300000002001104122540PMThursdayOctOctober1210/4/2001 4:25:40 PM631377951400000000