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Thanks to a connection fostered by my pal Guido over at Nearpod, I found out about a unique opportunity to do global professional development in 2 minutes flat. The #2minPD project is the brain-child of Stanford fellow Melissa Pelochino, whose goal … Continue reading →

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

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is The Phantom Tollbooth, by Norton Juster. It describes deep issues that thoughtful educators wrestle with daily: wisdom, friendship, trust, relationships between children and adults, and most importantly, knowledge.I remember it as one of my favorite books growing up, but I hadn't reread it in years. Lately, I've taken to reading to my daughter again before her bedtime, and I decided that I would read her books I thought she should know about but might not pick up on her own. I started with
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12:30 AM | I’m Going To TeachFest!

An email I’d been anxiously hoping for arrived in my inbox on Friday night. Dear Kyle,Congratulations! We are delighted to inform you that you have been selected to join LearnZillion’s 2014 Dream Team! It was longer than that, of course, but all I really needed to read was the first line. I’m one of 200 teachers […]

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Over the past week, there have been a number of comments on PubPeer — a site of which we’re big fans — about a 2007 paper in Oncogene. The comments suggested that the figures in the paper had problems. Some bands seemed to be duplicated, and one of the images looked very much like that […]

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Removing ‘barriers’ to education through free college textbooks By Emanuella Grinberg, CNN April 18, 2014 Link to article

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11:16 PM | OKCathy

This week’s Aunt Pythia column features Cathy O’Neil’s take on what questions online daters ought to have to answer in their profiles: How sexual are you? (super important question) How much fun are you? (people are surprisingly honest when asked this) How awesome do you smell? (might need to invent technology for this one) What bothers […]

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My article on whether we can trust airfare prediction models is published today at FiveThirtyEight, the new data journalism venture launched by Nate Silver after he moved to ESPN. This topic was originally conceived as a chapter of Numbersense (link) but I dropped it. As I have noted in my review of Nate Silver's book, he has a keen interest in evaluating predictions, and not surprisingly, he encouraged me to get this piece done. Putting Big Data to the Test Just like Google Flu Trends (link), […]

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10:58 PM | Linkfest for Sunday, April 20 (a small one)

Nat Banting on making practice more conceptual - ask students to do the last step in posing the problem. Nice!Andrew Knauft descrbies why he thinks Geogebra > Desmos. A site for finding, building, and storing formulas online, Formula Sheet. (hat tip to Glenn Waddell, whose diigo account may have inspired me to get one - which I don't use. Maybe I should ask him to teach me how to make it useful. I love his real posts, but his Diigo Links (Weekly) are often full of useful ideas too.)Malke
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10:43 PM | Remembering Nina Cassian

Exiled Romanian poet Nina Cassian (1924-2014) died last week in Manhattan. Cassian was an outspoken poet whom I admired for her political views; she also was connected to mathematics -- in her subject matter and her friends. (See, for example, this posting from January 31, 2011.) Equality by Nina Cassian If I dress up like a peacock, you dress like a
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10:14 PM | a day for comments

As I was flying over Skye (with [maybe] a first if hazy perspective on the Cuillin ridge!) to Iceland, three long sets of replies to some of my posts appeared on the ‘Og: Dan Simpson replied to my comments of last Tuesday about his PC construction; Arnaud Doucet precised some issues about his adaptive subsampling […]

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9:36 PM | Some Cute Integrals — U-Substitutions

Students of an introductory college-level Calculus sequence may eventually take a “Calculus II” course. This course is a main stay in the Engineering disciplines as well as a major in Mathematics. One of the main topics covered in this course is techniques of integration — u-substitution, integration by parts, trigonometric substitutions and trigonometric integrals, integration […]

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Esercizi da svolgere sui sistemi di disequazioni leggi articolo completo

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Esercizi da svolgere sulle disequazioni fratte di secondo grado. leggi articolo completo

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8:19 PM | Cost of light bulbs – New and improved

There’s a lot of misinformation out there about the cost to consumers of CFL and LED bulbs and the savings in energy and money that could be realized. Let your students “do the math” and realize some of the profit…Read more →

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8:04 PM | Teach Yourself Logic, new layout

The Teach Yourself Logic Guide has a new look. Now, instead of being a standard A4 PDF, it should be an ideal size for reading on screen. Read it either (i) on an iPad (download in Safari, open e.g. in … Continue reading →

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7:31 PM | Happy Passover and Happy Easter!

May everyone enjoy the holiday, whatever you celebrate! And if you don’t celebrate a specific tradition- Here’s to just living a happy life! Cheers All! Happy Mathing. Dr. Nicki

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The Common Core makes simple math more complicated. Here's why.: Libby Nelson:
You might not know what a number sentence is. Neither does Stephen Colbert, who recently suggested “word equation” and “formula paragraph” as nonsensical synonyms.
[source: mme rss]

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7:10 PM | Origami

Origami of impossible figures by Julien Lozi (origamaniac)
http://im-possible.info/english/art/sculpture/julien-lozi.html
Author - http://origamaniac.deviantart.com/

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Some of the world's greatest physicists couldn't tell you why our leading theory of everything is labelled "M". Amanda Gefter hit the road to solve the mystery

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6:53 PM | Discovery math debate rages on

Discovery math debate rages on: Daniele Alcinii:
A local school district is throwing its support behind discovery math despite mounting disapproval against its implementation in the provincial school curriculum.
[source: mme rss]

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Data Doesn’t Lie? The Fuzzy Math Behind the Search for MH370: Jeff Wise:
The March 25 report stated that Inmarsat had used a new kind of mathematical analysis to rule out a northern route. Without being very precise in its description, it implied that the analysis might have depended on a small but telling wobble of the Inmarsat satellite’s orbit. Accompanying the written report was an appendix, called Annex I, that consisted of three diagrams, the second of which was titled “MH370
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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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This section is devoted to studying the Gaussian Isoperimetric Inequality. This inequality is a special case of the Borell Isoperimetric Inequality (and hence also a special case of the General-Volume Majority Is Stablest Theorem); in particular, it’s the special case arising from the limit $\rho \to 1^{-}$. Restating Borell’s theorem using rotation sensitivity [...]

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5:48 PM | Learning Math without a Body

Last week was was a strange week of firsts for Math in Your Feet. I've been a teaching artist for about sixteen years and started exploring the connections between math and percussive dance in late 2003. Between 2004 and 2006 the program was piloted twice at all nine elementary schools in a large urban school district in Indianapolis, IN; prior to that I spent five years teaching clogging at many, many small, often isolated, rural schools across North Carolina, South Carolina and
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5:30 PM | Leapfrog Division II

A little over a year ago, I wrote up my Leapfrog Division post. It's about time for a modification!
The original technique showed you how to work out the decimal equivalent for fractions whose denominators end in 9. In today's post, you'll learn a similar technique for denominators ending in 1.
Before learning this technique, you do want to be very comfortable working with the original Leapfrog

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A method for making large amounts of the wonder material graphene is so simple that it can be done with kitchen appliances and Fairy Liquid

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4:58 PM | Finite Products Theories

I need a slight generalization of a classic result on algebraic theories. You may know who proved it!

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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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Un triangolo aureo è un triangolo isoscele in cui il rapporto tra uno dei lati uguali con la base è pari alla sezione aurea $\varphi$. Utilizzando un triangolo aureo di lato 1, è possibile dimostrare che \[1 + \frac{1}{\varphi^2} + \frac{1}{\varphi^4} + \cdots = \varphi\] \[\frac{1}{\varphi} + \frac{1}{\varphi^3} + \cdots = 1\] \[\frac{1}{\varphi} + \frac{1}{\varphi^2} + \frac{1}{\varphi^3} + \cdots = \varphi\] Il triangolo aureo qui sopra è lo screenshot della applet realizzata da Irina
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Edwards S. (2014). Proof Without Words: An Infinite Series Using Golden Triangles, The College Mathematics Journal, 45 (2) 120-120. DOI: 10.4169/college.math.j.45.2.120

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gfrblxt posted The best book written on education in the late 20th century on hyperbolic.guitars.home.

is The Phantom Tollbooth, by Norton Juster. It describes deep issues that thoughtful educators wrestle with daily: wisdom, friendship, trust, relationships between children and adults, and most importantly, knowledge.I remember it as one of my favorite books growing up, but I hadn't reread it in years. Lately, I've taken to reading to my daughter again before her bedtime, and I decided that I would read her books I thought she should know about but might not pick up on her own. I started with
[…]

2014-04-21 01:08:00

matthewmaddux posted The Common Core makes simple math more complicated. Here's why. on MatthewMaddux Education

The Common Core makes simple math more complicated. Here's why.: Libby Nelson:
You might not know what a number sentence is. Neither does Stephen Colbert, who recently suggested “word equation” and “formula paragraph” as nonsensical synonyms.
[source: mme rss]

2014-04-20 19:14:13

Discovery math debate rages on: Daniele Alcinii:
A local school district is throwing its support behind discovery math despite mounting disapproval against its implementation in the provincial school curriculum.
[source: mme rss]

2014-04-20 18:53:10

matthewmaddux posted Data Doesn’t Lie? The Fuzzy Math Behind the Search for MH370 on MatthewMaddux Education

Data Doesn’t Lie? The Fuzzy Math Behind the Search for MH370: Jeff Wise:
The March 25 report stated that Inmarsat had used a new kind of mathematical analysis to rule out a northern route. Without being very precise in its description, it implied that the analysis might have depended on a small but telling wobble of the Inmarsat satellite’s orbit. Accompanying the written report was an appendix, called Annex I, that consisted of three diagrams, the second of which was titled “MH370
[…]

2014-04-20 18:45:24

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 […]

2014-04-20 14:59:50

2014-04-20 13:05:15

rlgordonma posted Generalizing an already tough integral on Math math math math baked beans and math

I did the case $p=1$ here. The generalization to higher $p$ may involve higher-order derivatives as follows: $$\begin{align}K_p &= \int_0^{\pi/2} dx \frac{x^{2 p}}{1+\cos^2{x}} = \frac1{2^{4 p-1}} \int_{-\pi}^{\pi} dy \frac{y^{2 p}}{3+\cos{y}} \end{align}$$ So define, as before, $$J(a) = \int_{-\pi}^{\pi} dy \frac{e^{i a y}}{3+\cos{y}} $$ Then $$K_p = \frac{(-1)^p}{2^{4 p-1}} \left [\frac{d^{2 p}}{da^{2 p}} J(a) \right ]_{a=0}$$ […]

2014-04-20 01:20:32

료칸 미키야에서 체크인을 끝내고 밖으로 나와 봤습니다. 외양 온천 메구리를 즐기기 전에 일단 마을의 이곳저곳을 좀 돌아다녀 보기 위해서… 역시 평상복을 입고 돌아다니는 사람들보다 유카타를 걸치고 있는 사람들이 훨씬 많았습니다. 유카타를 보면 머물고 있는 료칸이 어딘지도 알 수 있죠! 7개의 … Continue reading →Related Posts ?[교토 쿠라마 여행 05] 쿠라마 온천
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2014-04-19 21:42:47

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