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allofthemath:
This, ladies and gentlemen and genderqueer folks, is Pascal’s tetrahedron, a three dimensional analogue of Pascal’s triangle, and it’s pretty freaking great.
I’ve never heard of this before!

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tigburr:
coolmathstuff:
allofthemath:
appliedmathemagics:
themathkid:
Can’t. Stop. Watching.
this is hypnotic…
Conic sections are all connected! A hyperbola is an anti circle, in this case.
Remember, the equation for a circle involves adding x squared and y squared, while the equation for a hyperbola involves subtracting one from the other. The other consequence of this is that is that if you extend the graph of either one to include imaginary and complex x or y values, a hyperbola
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Jordan Ellenberg offers an observation on why mathematicians (generally) are NOT sociopaths (unlike, perhaps, investment bankers ;-):http://quomodocumque.wordpress.com/2014/04/22/why-arent-math-professors-sociopaths/Meanwhile, possibly on the opposite end of the spectrum is Jason Padgett's story, which I've reported here previously -- an individual with "acquired" savant syndrome, that appeared later in life following significant brain trauma, recounted in Padgett's new volume "Struck by
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jtotheizzoe:
Happy Earth Day! Here is a new time-lapse of images from the International Space Station, titled The World Outside My Window. You may not be looking at it from this perspective, but you’ve got a world outside your window, too. Take care of it.
Turn up your speakers, go full screen, and lean back. Heck … this one even goes to 4K. Enjoy.
(video by David Peterson)

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2:00 PM | Cheesy Geometry Jokes

(function(jQuery) { function init() { wSlideshow.render({elementID:"850086446255391728",nav:"numbers" [...]

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5:00 AM | Hard-Boiled

(Click on the cartoon to see the full image.) (C)Copyright 2014, C. Burke.That's the yolk. I was working on the monologue for a while before I realized if anyone were willing to read more that two paragraphs of my prose, I could sell a few stories. I couldn't tag this one "PI", because it's not "pi". And if I make a new "P.I." tag, I'd have to go back and tag most of the "Pi" comics.

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A terrorist attack is underway and this will be the longest day of your life. Are you going to survive it? Jack is back with a brand new season of 24. The title of day 9, Live Another Day, is a reminder that just surviving a day of 24 is a success. And that raises […]

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10:30 PM | Family Math

Just filling some time today passing along this li'l algebraic Friday puzzler that Richard Wiseman offered last week (I've re-stated it slightly):In a certain family with 2 or more children, each daughter has the SAME number of brothers as she has sisters, while each son has TWICE as many sisters as brothers. How many sons and daughters are in this family?answer below:.................answer: 4 daughters & 3 sons

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Προβληματάκι δυο σε ένα... Ο Συνταγματάρχης Παπαδόπουλος είναι διοικητής του στρατοπέδου της Λοξολάνδης και αντιμετωπίζει το εξής πρόβλημα: Εικοσιπέντε αξιωματικοί είναι τοποθετημένοι (ένας –ένας) στα τετραγωνικά δωμάτια του 5 × 5 τετραγωνικού
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digg:
Probably the greatest machine man has ever created

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Here’s yet another intro to mathematical thinking MOOC. Loughborough University, and in particular Professor Tony Croft, is offering a course called “Getting a grip on mathematical symbolism” through the FutureLearn platform. It starts on the 28th of April. There isn’t much information about the course online yet, apart from the brief description on the official... Read more »

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3:26 PM | The Calculus of History

the paper I’d assign to a calculus class if everyone shared my slightly skewed sense of intellectual fun and my excessive fondness for mathematical metaphors Continue reading →

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“Fun”, “Laughter”, “Play” and “Excitement” are words not usually associated with mathematics. For almost obvious reasons, “Dread” lies among the top list of words that come to mind when one […]

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Often, when we purchase a product we do not even think of the processes that have to take place in order for the product to reach our hands. So much is involved on the back end of things. Tammy Landrum is the purchasing coordinator BSF, Inc., and she understands the entire process including the math. Can […]

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From the numbers 1, 2, … n, start by writing an odd number, and keep writing larger numbers–alternating between even and odd–until you stop at n. Call this an odd-even sequence of n. For example, if n = 3, then the only odd-even sequences are 123 and 3. If n = 8, then the sequences […]

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FINALLY!!! I got 2048!!! YES!!! FUCK YEAH!!! Hey, where did my family go…

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9:28 PM | What’s it about women and science?

Simplistic, but quite to the point… “I’ve never been female, but I’ve been black all my life and so let me perhaps offer some insight from that perspective. I got to see how the world around me reacted to my expressions of these ambitions. All I can say that is the fact that I wanted […]

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matthen:
Transforming from ellipses to hyperbolas, by considering slowly changing the equation (a circle) into the equation a (hyperbola). The purple lines represent different ‘radiuses’. I’ve been a bit obsessed with conic sections recently! [code]

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4:18 PM | Happy Easter 2014

(Click on the cartoon to see the full image.) (C)Copyright 2014, C. Burke.That's only for fresh eggs. It's okay to put hard-boiled eggs in one basket because you want them all to break so you have an excuse to throw them all out! Seriously, I know some people who eat them, but I know few who enjoy them.

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2:59 PM | To a Tetrahedral Birthday

BIRTHDAY CHALLENGE: Try creating a tetrahedron-like structure (regular triangular pyramid) with 20 balls or spheres. Today’s the 20th of April and the birthday of an Evertonian – which explains the image of […]

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12:00 PM | S6.219 - Heart of Gold

SERIES 6 INDEXThe Story So Far: After leaving Fractal City, personified math must deal with a wormhole that could bring them to Statistics... help point the way back home... or destroy them outright."All we need now, is to see if our distance and direction pair can spot mathematics," Dr. Nisano concluded, careful not to speak too loud. "If so, we hop on the gazebo and go!" Magnitude & Sign reunitedMaud and Signum eyed each other. Then they both extended out an arm, joining hands and
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8:48 AM | Traffic Simulation Video

To go along with my last post, here is a video of the traffic simulation. The quality isn't great, but I'm browsing through some video recording software to find the perfect one. Any suggestions would be greatly appreciated! Until then, enjoy :)

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A large chunk of machine learning (although not all of it) is concerned with predictive modeling, usually in the form of designing an algorithm that takes in some data set and returns an algorithm (or sometimes, a description of an algorithm) for making predictions based on future data. In terminology more friendly to the philosophy […]

Bailey, D., Borwein, J., de Prado, M.L. & Zhu, Q. (2014). Pseudo-Mathematics and Financial Charlatanism: The Effects of Backtest Overfitting on Out-of-Sample Performance, Notices of the American Mathematical Society, 61 (5) 458. DOI: 10.1090/noti1105

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Here the monotonicity of the EM algorithm is established. $$ f_{o}(Y_{o}|\theta)=f_{o,m}(Y_{o},Y_{m}|\theta)/f_{m|o}(Y_{m}|Y_{o},\theta)$$ $$ \log L_{o}(\theta)=\log L_{o,m}(\theta)-\log f_{m|o}(Y_{m}|Y_{o},\theta) \label{eq:loglikelihood} $$ where \( L_{o}(\theta)\) is the likelihood under the observed data and \(L_{o,m}(\theta)\) is the likelihood under the complete data. Taking the expectation of the second line with respect to the conditional distribution of
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Ruslan R Salakhutdinov, Sam T Roweis & Zoubin Ghahramani (2012). On the Convergence of Bound Optimization Algorithms, arXiv, arXiv: 1212.2490v1

Wu C.F.J. (1983). On the Convergence Properties of the EM Algorithm, The Annals of Statistics, 11 (1) 95-103. DOI: 10.1214/aos/1176346060

McLachlan G. & Peel D. DOI: 10.1002/0471721182

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by @ulaulaman about #exoplanets #planetary_transit #kepler_mission #nasa #astronomy The search for extrasolar planets (or exoplanets) had its first success in 1991 with the discovery of some planets orbiting around the pulsar PSR1257+12(1, 2, 3), measuring the variations of the radio pulses coming from the star. The second important milestone in exoplanet research takes place in 1995, with the discovery around the star 51 Pegasi (a star like our Sun) of a Jupiter-like planet, found at a […]

Wolszczan, A. & Frail, D. (1992). A planetary system around the millisecond pulsar PSR1257 + 12, Nature, 355 (6356) 145-147. DOI: 10.1038/355145a0

Wolszczan, A. (1994). Confirmation of Earth-Mass Planets Orbiting the Millisecond Pulsar PSR B1257 + 12, Science, 264 (5158) 538-542. DOI: 10.1126/science.264.5158.538

Mayor, M. & Queloz, D. (1995). A Jupiter-mass companion to a solar-type star, Nature, 378 (6555) 355-359. DOI: 10.1038/378355a0

Borucki, W., Koch, D., Basri, G., Batalha, N., Brown, T., Caldwell, D., Caldwell, J., Christensen-Dalsgaard, J., Cochran, W., DeVore, E. & Dunham, E. (2010). Kepler Planet-Detection Mission: Introduction and First Results, Science, 327 (5968) 977-980. DOI: 10.1126/science.1185402

Lissauer, J., Fabrycky, D., Ford, E., Borucki, W., Fressin, F., Marcy, G., Orosz, J., Rowe, J., Torres, G., Welsh, W. & Batalha, N. (2011). A closely packed system of low-mass, low-density planets transiting Kepler-11, Nature, 470 (7332) 53-58. DOI: 10.1038/nature09760

George, S. (2011). Extrasolar planets in the classroom, Physics Education, 46 (4) 403-406. DOI: 10.1088/0031-9120/46/4/004

LoPresto, M. & McKay, R. (2005). An introductory physics exercise using real extrasolar planet data, Physics Education, 40 (1) 46-50. DOI: 10.1088/0031-9120/40/1/003

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Non voglio fare concorrenza alla splendida spiegazione di Amedeo o a quella tecnica di Corrado, ma mia sorella, leggendo il post di pancia scritto nella sera dell'annuncio di BICEP2, ha candidamente confessato di non aver capito cosa era accaduto quel giorno. E allora proviamoci, a raccontarlo. (da The Cartoon History of the Universe #1 di Larry Gonick)C'era una volta un'idea di universo, che era la Terra al centro, quindi il Sole, la Luna e gli altri pianeti e sullo sfondo le stelle fisse,
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Hubble E. (1929). A relation between distance and radial velocity among extra-galactic nebulae, Proceedings of the National Academy of Sciences, 15 (3) 168-173. DOI: 10.1073/pnas.15.3.168

Gamow G. (1948). The Evolution of the Universe, Nature, 162 (4122) 680-682. DOI: 10.1038/162680a0

Alpher R.A. & Herman R. (1948). Evolution of the Universe, Nature, 162 (4124) 774-775. DOI: 10.1038/162774b0

Alpher R., Bethe H. & Gamow G. (1948). The Origin of Chemical Elements, Physical Review, 73 (7) 803-804. DOI: 10.1103/PhysRev.73.803

Peebles P.J.E., Schramm D.N., Turner E.L. & Kron R.G. (1994). The Evolution of the Universe, Scientific American, 271 (4) 52-57. DOI: 10.1038/scientificamerican1094-52

McLeish T.C.B., Bower R.G., Tanner B.K., Smithson H.E., Panti C., Lewis N. & Gasper G.E.M. (2014). History: A medieval multiverse, Nature, 507 (7491) 161-163. DOI: 10.1038/507161a

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Much of my undergrad was spent studying physics, and although I still think that a physics background is great for a theorists in any field, there are some downsides. For example, I used to make jokes like: “soft isn’t the opposite of hard sciences, easy is.” Thankfully, over the years I have started to slowly […]

Lazer, D., Kennedy, R., King, G. & Vespignani, A. (2014). Big data. The parable of Google Flu: traps in big data analysis., Science, 343 (6176) 1203-1205. PMID: 24626916

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wpgaurav tweeted: @wpgaurav

My mobile number is a prime number http://t.co/AjZSGi8NUD

2014-04-23 07:35:00

christianp tweeted: @christianp

Heh, nice 404 page on the @maanow website. http://t.co/FUYOzV1cgK

2014-04-23 07:34:06

wpgaurav tweeted: @wpgaurav

5 Powerful Ways to Help Your Website Grow in 2014 http://t.co/HfBNH2LN35

2014-04-23 07:30:07

rmathematicus tweeted: @rmathematicus

Somethin's Coming http://t.co/rfCFckZbIE

2014-04-23 06:51:29

ulaulaman tweeted: @ulaulaman

2014-04-23 06:40:01

wpgaurav tweeted: @wpgaurav

ThePensters – Get your essay done! http://t.co/w0SKU26h7L

2014-04-23 06:31:07

ulaulaman tweeted: @ulaulaman

Non so... Sono quasi sicuro che Fabrizio Totera sia stato mio compagno di classe alle scuole medie... http://t.co/TVxLiDaExW

2014-04-23 06:30:34

wpgaurav tweeted: @wpgaurav

Abel Prize Laureates http://t.co/O3ODV61GrA

2014-04-23 06:30:04

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