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Philip Durbin
Works at Harvard and greptilian.com
Lives in Boston
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Philip Durbin

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"For 15 years the National Institutes of Health and other agencies spent $40 million trying — and never quite succeeding — to devise algorithms that could spot a growing neurologic storm. Then a frustrated group of epilepsy physicians invited computer nerds around the world to take a shot instead, providing data sets recorded from the brains of human epilepsy patients and epileptic dogs.

Three months — and $30,000 of prize money — later, the winners had produced algorithms predicting seizures with better than 84 percent accuracy."

http://discovermagazine.com/2015/dec/crowdsourced-seizure-prediction
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"any system designed around the average person is doomed to fail"

Great read.
 
Fascinating...
In the early 1950s, a young lieutenant realized the fatal flaw in the cockpit design of U.S. air force jets. Todd Rose explains in an excerpt from his book, The End of Average.
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Just another average article.  (Hey C'mon, it's getting late and all).

It does make you think: what other averages are we suffering today?
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Krita has animation support now and it's fantastic! Make your own flip books! My thoughts and experiments so far: http://wiki.greptilian.com/krita
 
I tested today #krita animation branch for first time, and I fell in love with it ! Here is a very sketchy jumpy first test Carrot.
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The Martian got dropped on my desk yesterday afternoon and I just finished it. It was quite good.

https://en.wikipedia.org/wiki/The_Martian_(Weir_novel)

Now I'd like to see the movie. :)
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Dropped on my desk by +William Horka . Thanks!
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Open Source Release of TensorFlow

I'm very excited to announce the open source release of the TensorFlow machine learning library that I and many others at Google have been building.

This blog post gives an overview:
  http://googleresearch.blogspot.com/2015/11/tensorflow-googles-latest-machine_9.html

The web site has a number of tutorials and documentation about the system:
  http://tensorflow.org

The source is on GitHub:
  https://github.com/tensorflow/tensorflow

You might also be interested in the whitepaper we've prepared that describes TensorFlow in more detail:
  http://tensorflow.org/whitepaper2015.pdf

We'd love to hear what people think.
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Philip Durbin

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Handy new tool (built on top of githubarchive.org dataset!) that aggregates all of your GitHub activity: bit.ly/1mraQyT.

Apparently I've contributed to 248 repositories.. that's more than I would have guessed!
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Doesn't work on a phone, the search box is missing. 
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In "Concurrency is not Parallelism" by +Rob Pike he uses the following definitions:

Concurrency is the composition of independently executing things, typically functions (think abstractly but in practice the things are threads, coroutines, processes, etc.).

Parallelism is the simultaneous execution of multiple things, (possibly related) computations.

Concurrency is about dealing with a lot of things at once (structure).

Parallelism is about doing a lot of things at once (execution).

Concurrency is way to structure a thing so you can use parallelism to do a better job, but parallelism is not the goal of concurrency.

He recommends reading C. A. R. Hoare: Communicating Sequential Processes (CACM 1978): https://dx.doi.org/10.1145%2F359576.359585

The slides are at http://talks.golang.org/2012/waza.slide and the video at https://www.youtube.com/watch?v=cN_DpYBzKso via http://blog.golang.org/concurrency-is-not-parallelism

Here's a drawing of gophers burning C++ manuals that demonstrates a concurrent design that has been made parallel by doubling everything.

The book pile is web content. The gophers are CPUs. The cart is networking. The incinerator is the browser, the consumer of the data. It's a web serving architecture.

Great talk.
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http://fivethirtyeight.com/features/not-even-scientists-can-easily-explain-p-values/

"Imagine, he said, that you have a coin that you suspect is weighted toward heads. (Your null hypothesis is then that the coin is fair.) You flip it 100 times and get more heads than tails. The p-value won’t tell you whether the coin is fair, but it will tell you the probability that you’d get at least as many heads as you did if the coin was fair. That’s it — nothing more. And that’s about as simple as I can make it, which means I’ve probably oversimplified it and will soon receive exasperated messages from statisticians telling me so."


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Nice diagram of features, bugs, architecture, and technical debt.
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""Veterans' Day" with an apostrophe is "another potentially right way" says +Grammar Girl at http://www.quickanddirtytips.com/education/grammar/why-doesn%E2%80%99t-%E2%80%9Cveterans-day%E2%80%9D-have-an-apostrophe /cc @scholarsportal:)"- https://twitter.com/philipdurbin/status/664469427119890432

I'm also wondering about "Developers' Guide" vs "Developers Guide": http://irclog.greptilian.com/sourcefu/2015-11-11#i_146136

And Scholars Portal ( http://scholarsportal.info ) is absolutely awesome but I'd be happy to read an explanation of why there's no apostrophe. :)

If I were making a sign I think I'd choose "Farmers' Market" over "Farmers Market".

In that post +Grammar Girl says, "I should note that there are credible people who firmly believe an apostrophe is required on phrases such as “Veterans Day” and “farmers market.” It can be a contentious topic, and ultimately it’s a style choice. You may have to defend your choice no matter which one you make." I guess I'm in that camp.

She also says, "I can’t find the reference, but I remember reading somewhere that it’s becoming more common for people to drop the apostrophe and choose the adjective form." +Grammar Girl (or anyone) if you do find that reference, please let me know!

See also http://english.stackexchange.com/questions/18999/when-can-a-noun-be-used-attributively

Happy #veteransday ! :) #grammar #englishminor #formerenglishtutor #ocd
This week in the United States we celebrate Veterans Day, a holiday to remember the end of World War I in 1918, but the name of the holiday brings up a common question: Do we need an apostrophe in the word “Veterans”? The short answer is no, because the U.S. government gave the holiday
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A Last Gift from Ramanujan

Srinivasa Ramanujan is a legend of the mathematics world. The son of a shop clerk in rural India, he taught himself mathematics, primarily out of a book he borrowed from the library. The math that he did started out as rediscovering old results, and then became novel, and ultimately became revolutionary; he is considered to be one of the great minds of mathematical history, someone routinely mentioned in comparison with names like Gauss, Euler, or Einstein.

Ramanujan's work became known beyond his village starting in 1913, when he sent a letter to the British mathematician G. H. Hardy. Ramanujan had been spamming mathematicians with his ideas for a few years, but his early writing in particular tended to be rather impenetrable, of the sort that today I would describe as "proof by proctological extraction:" he would present a result which was definitely true, and you could check that it was true, but it was completely incomprehensible how he got it. But by the time he wrote to Hardy, both his clarity and the strength of his results had improved, and Hardy was simply stunned by what he saw. He immediately invited Ramanujan to come visit him in Cambridge, and the two became lifelong friends. 

Alas, his life was very short: Ramanujan died at age 32 of tuberculosis (or possibly of a liver parasite; recent research suggests this may have been his underlying condition), less than six years after his letter to Hardy.

When we talk about people whose early death was a tremendous loss to humanity, there are few people for whom it's as true as Ramanujan, and a recent discovery in his papers has just underlined why.

This discovery ties together two stories separated by centuries: The "1729" story, and the great mystery of Pierre Fermat's last theorem.

The 1729 story comes from a time that Hardy came to visit Ramanujan when he was ill. In Hardy's words: 

"I remember once going to see him when he was ill at Putney. I had ridden in taxi cab number 1729 and remarked that the number seemed to me rather a dull one, and that I hoped it was not an unfavorable omen. 'No', he replied, 'it is a very interesting number; it is the smallest number expressible as the sum of two cubes in two different ways.'"

This has become the famous Ramanujan story (and in fact, 1729 is known to this day as the Hardy-Ramanujan Number), because it's just so ludicrously Ramanujan: he did have the reputation of being the sort of guy to whom you could mention an arbitrary four-digit number, and he would just happen to know (or maybe figure out on the spot) some profound fact about it, because he was just that much of a badass.

The other story is that of Fermat's Last Theorem. Pierre de Fermat was a 17th-century French mathematician, most famous for a theorem he didn't prove. In 1637, he jotted down a note in the margins of a book he had, about a generalization of the Pythagorean Theorem.

From Pythagoras, we know that the legs and hypotenuse of a right triangle are related by a²+b²=c². We also know that there are plenty of sets of integers that satisfy this relationship -- say, 3, 4, and 5. Fermat asked if this was true for higher powers as well: that is, when n>2, are there any integers a, b, and c such that aⁿ+bⁿ=cⁿ? He claimed that the answer was no, and that "he had a truly marvelous proof of this statement which was, unfortunately, too large to fit in this margin."

The consensus of mathematicians ever since is that Pierre de Fermat was full of shit: he had no such proof, and was bluffing.

In fact, this statement -- known as Fermat's Last Theorem, as his notes were only discovered after his death -- wasn't proven until 1995, when Andrew Wiles finally cracked it. Wiles' success was stunning because he didn't use any of the traditional approaches: instead, he took (and significantly extended) a completely unrelated-seeming branch of mathematics, the theory of elliptic curves, and figured out how to solve this. That theory is also at the heart of much of modern cryptography, not to mention several rather unusual bits of physics. (Including my own former field, string theory)


And so these two stories bring us to what just happened. A few months ago, two historians digging through Ramanujan's papers were amused to find the number 1729 on a sheet of paper: not written out as such, but hidden in the very formula which expresses that special property of the number, 9³+10³=12³+1. 

What turned this from a curiosity into a holy-crap moment was when the rest of the page, and the pages that went with it, suddenly made it clear that Ramanujan hadn't come up with 1729 at random: that property was a side effect of him making an attempt at Fermat's Last Theorem.

What Ramanujan was doing was looking at "almost-solutions" of Fermat's equation: equations of the form aⁿ+bⁿ=cⁿ±1. He had developed an entire mechanism of generating triples like these, and was clearly trying to use this to home in on a way to solve the theorem itself. In fact, the method he was using was precisely the method of elliptic curves which Wiles ended up using to successfully crack the theorem most of a century later.

What makes this completely insane is this: Wiles was taking a previously-separate branch of mathematics and applying it to a new problem.

But the theory of elliptic curves wasn't even invented until the 1940's.

Ramanujan was making significant progress towards solving Fermat's Last Theorem, using the mathematical theory which would in fact prove to be the key to solving it, while making up that entire branch of mathematics sort of in passing.

This is why Ramanujan was considered one of the greatest badasses in the history of mathematics. He didn't know about 1729 because his head was full of random facts; he knew about it because, oh yes, he was in the middle of doing yet another thing that might restructure math, but it didn't really solve the big problem he was aiming at so he just forgot about it in his stack of papers.

I shudder to imagine what our world would be like if Ramanujan had lived a longer life. He alone would probably have pushed much of mathematics ahead by 30 or 40 years.


If you want to know more about elliptic curves, Fermat, and how they're related, the linked article tells more, and links to more still. You can also read an outline of Ramanujan's life at https://en.wikipedia.org/wiki/Srinivasa_Ramanujan , and about Fermat's Last Theorem (and why it's so important) at https://en.wikipedia.org/wiki/Fermat%27s_Last_Theorem .
Ramanujan's manuscript. The representations of 1729 as the sum of two cubes appear in the bottom right corner. The equation expressing the near counter examples to Fermat's last theorem appears further up: α3 + β3 = γ3 + (-1)n. Image courtesy Trinity College library. Click here to see a larger ...
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