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One Hundred Interesting Mathematical Calculations, Number 7: Archive Entry From Brad DeLong's Webjournal

One Hundred Interesting Mathematical Calculations, Number 7 One Hundred Interesting Mathematical Calculations, Number 7: Julius Caesar's Last Breath What's the chance that the breath you just inhaled contains at least one air molecule that was in Julius Caesar's last breath--the one in which he said (according to Shakespeare) " Et tu Brute ? Then die Caesar"? Assume that the more than two thousand years that have passed have been enough time for all the molecules in Caesar's last breath to mix evenly in the atmosphere, and that only a trivial amount of the molecules have leaked out into the oceans or the ground. Assume further that there are about 10 44 molecules of air, and about 2 x 10 22 molecules in each breath--yours or Caesar's. That gives a chance of 2 x 10 22 /10 44 = 2x 10 -22 that any one particular molecule you breathe in came from Caesar's last breath. [1-2x10 -22 ] [2x10^22] How to evaluate this? [e [-2x10^(-22)] ] [2x10^(22)] From John Allen Paulos's Innumeracy .

infoverse - octomatics One Hundred Interesting Mathematical Calculations, Number 9: Archive Entry From Brad DeLong's Webjournal One Hundred Interesting Mathematical Calculations, Number 9 One Hundred Interesting Mathematical Calculations, Number 9: False Positives Suppose that we have a test for a disease that is 98% accurate: if one has the disease, the test comes back "yes" 98% of the time (and "no" 2% of the time), and if one does not have the disease, the test comes back "no" 98% of the time (and "yes" 2% of the time). Your test comes back "yes." Suppose just for ease of calculation that we have a population of 10000, of whom 50--one in every two hundred--have the disease. If you test "no" you can be very happy indeed: there is only one chance in 9752 that you are the unlucky guy who had the disease and yet tested negative. If you test "yes" you are less happy. From John Allen Paulos's Innumeracy .

Ten Fun Facts Of The Week ← Previous Post Next Post → Ten Fun Facts Of The Week jon July 8, 2011 1 For more fun facts, click HERE Related Pic Dumps: 23 Scary Moments Chuck Norris Facts (11 Pics) The Trees Are Hungry (13 Pics) Oh Shit Moments (45 Pics) Bad Jobs (23 Pics) Other Stuff You Might Also Like» The 9 Most Unusual Models On The Planet The Greatest Resignation Letter Of All Time The 20 Most Horrifying Sports Faces How Dead Rock & Roll Legends Would Look Today Were Your Prom Pictures This Embarrassing? How Deaf People Think How Spam Came to Mean Junk Mail How to Remove Stripped Screws Origin of the Words Geek and Nerd 10 Interesting Celebrity Facts 10 Interesting Human Body Facts 8 Interesting Facts About Businesses Quick Facts Rage Comics This Day in History One Comment » GOSH!! Leave A Response » Facts via TodayIFoundOut.com 23,775 SubscribersEmail marketing powered by MailChimp Interesting Facts on Facebook Recent Posts Famous Quotes (5 Pics) March 26, 2012, No Comments Funny Definitions (10 Pics) March 26, 2012, No Comments Popular

8 Things Everybody Ought to Know About Concentrating “Music helps me concentrate,” Mike said to me glancing briefly over his shoulder. Mike was in his room writing a paper for his U.S. History class. On his desk next to his computer sat crunched Red Bulls, empty Gatorade bottles, some extra pocket change and scattered pieces of paper. In the pocket of his sweat pants rested a blaring iPod with a chord that dangled near the floor, almost touching against his Adidas sandals. On his computer sat even more stray objects than his surrounding environment. Mike made a shift about every thirty seconds between all of the above. Do you know a person like this? The Science Behind Concentration In the above account, Mike’s obviously stuck in a routine that many of us may have found ourselves in, yet in the moment we feel it’s almost an impossible routine to get out of. When we constantly multitask to get things done, we’re not multitasking, we’re rapidly shifting our attention. Phase 1: Blood Rush Alert Phase 2: Find and Execute Phase 3: Disengagement

How to Disagree March 2008 The web is turning writing into a conversation. Twenty years ago, writers wrote and readers read. The web lets readers respond, and increasingly they do—in comment threads, on forums, and in their own blog posts. Many who respond to something disagree with it. That's to be expected. The result is there's a lot more disagreeing going on, especially measured by the word. If we're all going to be disagreeing more, we should be careful to do it well. DH0. This is the lowest form of disagreement, and probably also the most common. u r a fag!!!!!!!!!! But it's important to realize that more articulate name-calling has just as little weight. The author is a self-important dilettante. is really nothing more than a pretentious version of "u r a fag." DH1. An ad hominem attack is not quite as weak as mere name-calling. Of course he would say that. This wouldn't refute the author's argument, but it may at least be relevant to the case. DH2. DH3. DH4. DH5. DH6. What It Means Related:

Industry veteran: LimeWire pirates were iTunes’ best customers Internet pirates are always portrayed as parasitic freeloaders responsible for countless instances of DRM, the "death" of PC gaming, ISP bandwidth caps and more, but according to one industry veteran, that's entirely unfair. During a keynote speech at CA Expo in Sydney, former Google CIO and EMI executive Douglas C. Merrill said that he believes filesharers shouldn't be punished for downloading copyrighted material because it often drives them to make legitimate purchases. While employed by EMI (one of the world's largest music labels and an RIAA member), Merrill supposedly profiled LimeWire users and discovered that they were actually some of the biggest spenders on iTunes. "That's not theft, that's try-before-you-buy marketing and we weren't even paying for it… so it makes sense to sue them," Merrill said sarcastically. In an amusing analogy, he said that suing people for filesharing "is like trying to sell soap by throwing dirt on your customers."

What You'll Wish You'd Known January 2005 (I wrote this talk for a high school. I never actually gave it, because the school authorities vetoed the plan to invite me.) When I said I was speaking at a high school, my friends were curious. I'll start by telling you something you don't have to know in high school: what you want to do with your life. If I were back in high school and someone asked about my plans, I'd say that my first priority was to learn what the options were. It might seem that nothing would be easier than deciding what you like, but it turns out to be hard, partly because it's hard to get an accurate picture of most jobs. But there are other jobs you can't learn about, because no one is doing them yet. And yet every May, speakers all over the country fire up the Standard Graduation Speech, the theme of which is: don't give up on your dreams. What they really mean is, don't get demoralized. Which is an uncomfortable thought. I'm not saying there's no such thing as genius. Upwind Ambition Corruption Now

The NASA Space Pen In this week's Friday funny, journalist and author Eugene Byrne looks at an amusing urban legend much beloved of engineers, and frequently used in management seminars because of its powerful moral about overcomplicated solutions. The story In the 1960s, the story goes, NASA realised that astronauts would need a special pen for recording data, instrument readings etc. when in space. NASA enlisted some of the finest minds in the country and set them to work. The truth Initially, American astronauts used pencils, too, but they weren't popular. It was actually an American pen manufacturer, Paul C Fisher (1913-2006) who came up with the solution in 1965. True, it did cost around a million dollars to develop, but that was all Fisher's money.

5 Seemingly Innocent Ways You Risk Your Identity Every Day We tend to think of identity theft as a crime perpetrated exclusively on stupid people. Sure, you don't fall for that Nigerian prince schtick and you don't send your login information to "official" emails that misspell "PayPal." Well, you'd best take a slice of humble pie, because there are lots of things that you do every day, that you're probably doing right now, that are putting your personal information at risk. Things like ... Playing Facebook Games Getty After a long, hard day of playing Facebook games and pretending to work, there's nothing quite as relaxing as heading home to unwind and play Facebook games without pretending to work. Getty"Before 'Farmville,' gin was the only thing that could get me through a day of work." We've already discussed how Zynga, the operators of "Farmville," are evil masterminds. But hey, 'Mafia Wars'! And we don't just mean they could see all those pictures of you drunkenly fingering that elephant pinata at your cousin's birthday blowout. Getty"Tits?

5 Insane Ways Words Can Control Your Mind On some level we already know that language shapes the way we think. We're automatically more afraid to fight a guy named Jack Savage than somebody named Peewee Nipplepuss, even if we've never seen either of them before. It's totally illogical, but you probably run into an example of that every day, and don't notice it. While we tend to think words are just sounds we make to express ideas, science is finding that language is more like a fun house mirror, warping what we see in mind-blowing ways. For instance ... Speaking English Makes Us More Likely to Blame People Let's say your roommate Steve is jumping on your bed. How will you answer? Keep in mind, Steve pulls this shit all the time. The answer largely depends on what language you speak. Stanford scientists did experiments on this, by having speakers of various languages watch videos featuring, in various situations, people breaking eggs or popping balloons, sometimes on purpose, sometimes on accident. Will nothing stop his madness?

The Acceleration of Addictiveness July 2010 What hard liquor, cigarettes, heroin, and crack have in common is that they're all more concentrated forms of less addictive predecessors. Most if not all the things we describe as addictive are. And the scary thing is, the process that created them is accelerating. We wouldn't want to stop it. No one doubts this process is accelerating, which means increasing numbers of things we like will be transformed into things we like too much. [2] As far as I know there's no word for something we like too much. The world is more addictive than it was 40 years ago. The next 40 years will bring us some wonderful things. Most people won't, unfortunately. These two senses are already quite far apart. Societies eventually develop antibodies to addictive new things. As knowledge spread about the dangers of smoking, customs changed. It took a while though—on the order of 100 years. In fact, even that won't be enough. Most people I know have problems with Internet addiction. Notes

Math Isn't Just Computation. So Why Is That All We Teach? - Education \n A reader named Monika Hardy recently noticed that I harp a lot on the importance of math when blogging about education. (Guilty as charged.) So, she sent me an excellent talk from the recent TEDGlobal event from this summer. The speaker is Conrad Wolfram, brother of Stephen Wolfram, the polyglot behind the applications Mathematica and Wolfram|Alpha, who runs the firm Wolfram Research. The elements of math, according to Wolfram are: posing questions, translating real world problems into mathematical language, performing computation, and translating mathematical answers into real world solutions. Computers should be doing those calculations. What about the processes needed to solve mathematical problems? Check out the video, it's really good stuff—at least, I think so. \n A reader named Monika Hardy recently noticed that I harp a lot on the importance of math when blogging about education. Computers should be doing those calculations.

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