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Yonatan Zunger
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Yonatan Zunger

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Making the rounds, ultimate origin unknown. I have to say that this is somewhat more accurate than the usual "tomato" explanation of stats.

(That is: strength is being able to crush a tomato; dexterity, to juggle one; constitution, to eat a bad tomato; intelligence, to know that a tomato is a fruit; wisdom, to know not to put it in fruit salad; charisma, to be able to sell a tomato-based fruit salad.)
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+Yonatan Zunger You forgot, "Bards are a legitimate class to play."
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+Andreas Schou's comments here are worthwhile; the linked article is mostly not.

A common mistake people make is to confuse the tactical with the strategic. If you want to achieve a goal, first define the goal, and then figure out how to get from where you are to there; don't start by asking yourself what you can do from where you are, because that just leads to an increasing sequence of moves, each of which may impose long-term costs, and none of which gets you any closer to where you wanted to be.

This is as much a problem in engineering as it is in politics.

One of its most common manifestations is people trying to fight symptoms while ignoring the cause – often because the cause is deep, requires some serious thinking to even identify, and requires a big, concerted effort to fix, one which will very likely produce few benefits in the short run but many in the long run, while dealing with the symptoms is all about the short term.

This isn't to say that you shouldn't deal with the symptoms: part of any good long-term plan is how you manage the short term on the way there. But there's a profound difference between fixing the symptoms in a way which moves you towards your long-term goal, and fixing them in a way which makes it harder to fix your long-term goal.

"Problem: Gentrification. Solution: Tank the economy!" would be a very good example of the latter, although most people don't phrase it quite so baldly.
"We have set up a system which breaks when more resources are added!" is a perfectly reasonable complaint about a system. However, "We should keep resources from being added so the system doesn't break!" is an insane solution to that problem. The problem is with the constraint built into the system; what the hell is wrong with you that you are designing everything around keeping that constraint.

The problem in San Francisco -- housing, traffic, et cetera -- boils down to "the economy is great because a fair proportion of America's fastest-growing companies are located there, and everyone wants to live there because it's a great city; this is causing land-use restrictions, rent control and public transit to implode."

The solution being offered is to fix the problem "the economy is great," so as to keep the city controlled by incumbents, and make it easier for broke incumbents to find new places to rent. This solves the problem by breaking the system at an even lower level. The correct answer to the question, "Would you rather be San Francisco or Detroit?" is, frankly, just a blank and merciless stare. 
The advent of Google Glass has started an incendiary new chapter in tech's culture wars. Here's what's at stake.
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For the rest of the full Valley package, my dad gave me a chunk of stock from his startup when I was thirteen, and told me it would pay for my college.

The startup involved laser discs. Needless to say, it did not pay for anything.

It gave me a much more realistic view of startups than most people during the Bubble. (And yet, I still worked at some. The apple doesn't fall far from the tree?)
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Neutrinos are the ghosts of the universe. They're particles which have no electric charge (as the "neutr-" in their name suggests), but also don't have any of the other kinds of charge that let neutrons be an important part of nuclear physics. They're produced as a side effect of fusion reactions -- in fact, they cart off nearly half the energy during supernovae! -- but they interact with matter so weakly that entire planets are basically transparent to them.

However, we want to study them. One of the most important questions about them has been whether they have any mass at all of their own, or whether (like photons) they have no mass at all, and can only travel at the speed of light. This is important because massive particles turn out to be different from massless ones in some fairly fundamental ways, and the existence of extra massive particles -- even ones with tiny masses -- would affect our understanding of things like particle physics and the early universe.

It turns out that we can find out about these masses in a clever way. There are three kinds of neutrino, named the electron, muon, and tau neutrinos. Ordinary fusion reactions (like the ones in the Sun) only produce electron neutrinos, and they produce them in a very predictable fashion: two neutrinos per atom fusing. So if we had a way to measure how many neutrinos we were seeing on Earth, and compare it to how much light the Sun emits, we could measure if any are "missing."

Why missing? Because it turns out that electron neutrinos can turn into muon or tau neutrinos, only if they are massive. (This is one of the ways that massive and massless particles are different) The Sun only produces electron neutrinos; our detectors can only detect electron neutrinos. If we measured any difference, we would know for certain that neutrinos had mass.

But how do you measure neutrinos, if they see entire planets as being transparent? The answer is that "transparent" means that the odds of a neutrino being stopped by any particular piece of matter are very, very, small. So what you need is a whole lot of matter, and a whole lot of neutrinos, and being able to count every single time one of them hits.

How do you do that? You build a giant tank and fill it with a solution that contains atoms that are capable of catching a neutrino in a predictable way. On those extremely rare occasions that this happens, an electron gets shot off at very high speed, and as the electron tries to move through the solution, it creates a flash of light. (Technically: this is Cerenkov Radiation, the light produced when something tries to fly faster than the speed of light in a medium. Cerenkov radiation is to light what a sonic boom is to sound.) 

You isolate this tank from absolutely anything else that could get into it -- which includes things like burying it in an old mineshaft, and purifying the solution so that there aren't any stray radioisotopes or anything into it.

You surround the tank with a lot of very sensitive light detectors.

You realize that you can't prevent everything that isn't a neutrino from getting in, so you figure out how to identify those other things by their distinctive light patterns.

And then you wait. The Sun fires about 2 million neutrinos through every square centimeter of your head every second; each will successfully strike an atom perhaps one time in 10^28. (Which means that one will actually interact with your body once in the lifetime of the universe or so)

How big a tank is "big enough?" The Super-Kamiokande detector, 1km under Japan, has a tank holding 50,000 tons of ultra-pure water, surrounded by over 11,000 photomultiplier tubes. The picture below shows the tank mostly drained for maintenance; that thing at the back is two people in a raft.

And over nearly two decades of work, the SuperK team managed to measure the Sun's neutrino flux, accurately enough and in enough different ways, to confirm a result that most physicists didn't expect: neutrinos indeed have mass. We still haven't been able to measure the mass -- we know that it's at least 40meV and at most about 200meV. (An eV is a unit of energy; it's roughly the energy that holds an electron into an atom. The mass of an electron is about 511keV, or about half a million eV; a proton, just under a billion eV. The neutrino mass is well under one eV)

So through building a tremendous tank of the purest water in the world, we have managed to see the faintest ghosts in all of nature.

Congratulations to Takaaki Kajita and Arthur B. McDonald, and to all of the hundreds of people who have worked on this problem in the past decades, for a well-deserved 2015 Nobel Prize in Physics.
This deserves a Nobel prize This is a picture of Super-Kamiokande, one of the neutrino detectors that won this year's physics Nobel prize.   It's a tank… - John Baez - Google+
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Thanks +Matt Austern​, you were faster than me. Yonatan explanation is awesome but he had to use shortcuts. Describing Standard Model might have taken a bit long.
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This result may seem like a serious case of "no shit?", but there's quite a lot of actual meat in the details of the study – not in the fact that when families suddenly became less poor, many aspects of their kids' lives and behavior improved, but in the particular ways that this happened.

Further evidence that under a nontrivial range of circumstances, simply giving people a regular supply of money – not "quit-your-job" scales of money, but "not-be-perpetually-one-flat-tire-from-eviction" money – can have very significant, and positive, knock-on effects across society as a whole.
Spoiler: when the parents have more money coming in they are able to better provide a home environment that encourages kids to learn and instills behaviors in them that lead to success in their adult lives.
Because imagine that. When people aren't constantly working to survive they actually like to better themselves and their kids.
Incredibly, the change is the most pronounced in the children who need it the most.
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I'm a little surprised that no one has mentioned Give Directly, the charity that vies cash directly to some of the poorest people on the planet and measures the impact that it has on their lives (through randomized controls). 

Short term results have shown large improvements in income, assets, and nutrition. Long term research is ongoing.

If long term results are consistent with what's been found so far it may be one of the most cost-effective ways to improve people's lives.
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Last Friday, the US bombed a hospital run by Médecins Sans Frontières (MSF) [1] in Kunduz, destroying it in a nearly hour-long raid with many of its patients and doctors still inside.

On Saturday, the official statement was that this had been a mistake, a mistargeting in the fog of war.

On Sunday, MSF pointed out that not only did they routinely give the GPS coordinates of the hospital to US forces (most recently five days before the bombing), but they had been on the phone with military officials during the strike trying to get them to stop, with the US nonetheless continuing to bomb for another half hour, and that on top of this the other buildings in the compound were undamaged even as just the hospital was destroyed.

On Monday, the US rolled back its story, claiming that the strike had been deliberate, but had been necessary because the Taliban was using the hospital as a base and had been firing out of it, pinning down US and Afghan forces and requiring close air support.

On Tuesday, as film reviewed by the AP demonstrated that this was not, in fact, the case, and that nobody had been firing anything from the hospital, the US rolled back its story yet again, and is now claiming that while there were a lot of civilian casualties in the hospital, the attack was nonetheless justified because there were a lot of senior Taliban members in the hospital who were also killed.

As MSF's General Director, Christopher Stokes, said on Sunday, these latest official US statements "[amount] to admission of a war crime;" at this point, the statements amount to "yes, we blew up a hospital with people in it, and yes, we did that on purpose, but we were justified in doing so."

[Edited to add: And on Wednesday, the administration admitted fault and promised a "transparent, thorough, and objective accounting" for what happened. h/t +Cory Lui]

What seems to be the case, and what most sources have started to concede, is that the Afghan government has long hated the existence of this particular hospital, as (like all MSF hospitals) it has been known to treat whoever was sick or injured and came through the door, no matter which side they were on. 

My best estimate of the underlying reasoning, at this point, has to do with the Obama administration's ongoing negotiations with the Afghan government about the pullout of remaining US forces, and their urge to make extra-nice with the Afghans -- say, by blowing up some hospitals for them -- to try to keep them on our side for a bit longer after we leave.

The article linked provides an excellent timeline, as well as quotes from all sides as the story unrolled, so that you can see how the official statements have shifted as each line became untenable in turn.

[1] Disclosure: You'll find me on their major donors list for the past decade.

[This post has been edited with a substantial rewrite for clarity, since I wrote the first draft half-asleep.]
We now have U.S. and Afghan officials expressly justifying the consummate war crime: deliberately attacking a hospital filled with doctors, nurses and wounded patients. And whatever else is true, the story of what happened here has been changing rapidly as facts emerge proving the initial claims to be false.
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+Andreas Geisler your claim, as to my lack of knowledge of the entire working of the US military, is laughable; and, BTW, "when did you stop beating your wife?"  The rest is some variation of post hoc fallacy.
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I can't say that Zack Weinersmith doesn't have a point: Ghostbusters may well be the most distilled rendering of America in film ever. Having conclusively proven the existence of life after death, our protagonists proceed to form a small business, and spend most of the movie on a combination of marketing, fighting with regulators, and trying to get laid.

Comedy works best when it's a painfully accurate reflection of the world around it, after all.
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+Bob Calder Baldrick always has a cunning plan. I'm sure it is just a question of time before he makes his entrance. Or maybe you're just not evil enough?
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Many years ago, in my dissolute youth as a theoretical physicist, I was a TA for Physics 61 at Stanford, aka "Freshman Physics for Masochists." (The unofficial names of the four versions of freshman physics being "... for poets," "... for med students," "... for engineers," and "... for masochists." 60-series was particularly famous for being, shall we say, rather hard-core.)

Apparently, +Kathryn Moler – who was teaching the class – still remembers me. And also apparently, the Stanford Daily immortalized our teaching of the class with a cartoon. 

Just to make it clear, both of us put fairly considerable effort into helping our students succeed, not just academically but in general as people. We did not actually fire anyone out of a cannon. Xor dip them in liquid nitrogen.

(All my messing with undergrads' minds using liquid nitro was done at the University of Colorado, and at Stanford I instead used things like lasers and radioactive sources)

Many thanks to +Sarah Lester for not only noticing this, but finding me a video clip.
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Here's a fascinating map, although a very preliminary one. It shows the rate of gun deaths in the US per 100,000 people. This doesn't have a breakdown of the type of death -- accident, suicide, homicide -- and they're just starting to look in to that. (For example, it appears that the high rate in rural Oregon is very dominated by suicides, about 4/5) The data comes from the CDC, and you can see a zoomed-in map at .

What's fascinating about this map is the extent to which it's non-uniform, and the extent to which that non-uniformity isn't obvious. Why are death rates so much lower in northern Utah than southern? Why does El Paso county have one of the lowest rates in the nation, but nearby Eddy county have one of the highest?

I don't see many maps of demographic trends where there's no immediately obvious explanation for the shapes, but this is definitely one of them. So I'm very much looking forward to seeing a deeper analysis of this.

Via +Steve S 
U.S. deaths by gunfire -- suicides, homicides and accidents -- numbered 33,636 in 2013, according to the Centers for Disease Control and Prevention. What's striking is how widely the death rate varies from one part of the nation to the next.
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+Steve S Or simply unreliable reporting in certain jurisdictions. Or weird jurisdictional overlaps; given the importance of the Border Patrol in El Paso, for example, it's quite possible that deaths which they consider to be in their jurisdiction aren't reported through the same channels as deaths which happen in the county's jurisdiction, and so one or the other gets lost.
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I find +A.V. Flox's comments here significantly more interesting than Jim Dowd's article, especially what she says about the broader role that feminism [/all sorts of other related isms] needs to play. Men suffer profoundly from very broken gender expectations -- in ways that are very different from the ways that women suffer, but in very real ways nonetheless. And these are no more OK than broken gender expectations affecting anybody else.
In this piece, Jim Dowd argues that mass shootings aren't senseless, but driven by entitlement -- entitlement to power, access to sexual partners and other things that we as a society equate with success. When men fail to attain that to which they feel entitled, they become violent, whether they happen to be in Saudi Arabia or the United States.

In this country, it frequently comes down to sex. Men feel entitled to access to women, and despite the fear-mongering about permissive sexuality and hookup culture, many of the men that resort to these horrific crimes have previously been unable to find sexual partners.

It's easy to see how Dowd arrives at these conclusions, but it's difficult to accept his ultimate point: that the onus is on us to make sure men don't get left out. What does that mean, exactly? Should we privilege men because they might turn to violence if we don't? Letting men have the jobs instead of more qualified women or transgender folks because they'll shoot up the office if we don't? How many women and trans women (and even men and trans men) sleep with men they'd rather not because saying "no" might lead to violence?

No, I don't agree that we should walk on eggshells because someone feels entitled to something they have not earned, or something another party doesn't want to participate in. The solution isn't that. But I do see how we may participate in a solution to address the root of the entitlement. However, in order to do that, we need to interrogate the messages we collude in reinforcing in our society about what it means to be a man in the same way we are interrogating what it means to be a woman.

Despite the steps forward feminism has made to challenge sexism as it relates to women, a lot of sexist ideas relating to men continue to go unaddressed. A recent example is the mockery surrounding that group of men who determined to actively choose celibacy or limited relationships to deal with the powerlessness they feel. The mockery they faced signaled not only to them, but to all men, once again, that to be a man and not be sexual or maintain viable relationships is to face certain ridicule.

If feminism is about equality, it must address the constructs that dictate a man is only valuable if he's financially or sexually successful, just as it does the constructs that a woman's worth is dictated by her caretaking and sexual "purity." It must acknowledge that men can be subject to sexual violence, human trafficking, and domestic abuse. Men may perpetrate a significant fraction of these crimes, but that doesn't mean men are immune to them. Failure to acknowledge this is to reinforce an aspect of the structure we're trying to bring down.

This isn't about coddling. It's about continuing what we're doing to dismantle toxic social and gender constructs. Changing gun laws will likely decrease these senseless acts, but these are a symptom -- gender messaging is the disease.
Every time there is a mass shooting (which on average is every sixty four days) one of the key words we hear describing the tragedy is “senseless.” This would suggest the action was without meaning...
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+Pistolero Jesse sorry, no I haven't.
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I am pretty sure that, if there is a heaven, this is what part of it looks like.

(Thanks also to +Autumn Ginkgo Leaves™ for making sure I didn't miss the post)
Now this is a library. 
The capital of the Czech Republic, Prague, holds one of the most stunning Libraries in the world: The Clementinum Library.  The …
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+Anne-Marie Clark​ That sounds disturbingly like the onset of a transformational process. Have you noticed how those drawn to libraries - especially students and bibliophiles - often develop a stooped posture, deteriorating vision and a preference for quiet?

Has anyone checked that the number of humans leaving these highly attractive places matches the number entering? And how does that compare to the bat population? Are we sure that "libraries" are not lures?
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This statue is something I've loved since I first heard of it; it stands in honor of the extraordinary contributions that rodents – lab mice and lab rats – have made to science. The Institute hopes to make this into a series, honoring a wide range of species.
"The statue stands six feet tall and sits near the Institute of Cytology and Genetics in Novosibirsk, Russia. According to the artist, Andrew Kharevich:

It combines the image of the laboratory mouse and a scientist, because they are related to each other and serve as one case. Mouse is captured in a moment of scientific discovery. If you look into her eyes, you can see that this little mouse has come up with something. But the whole symphony of scientific discovery, joy, “eureka” has not yet begun to sound."
A symbol of gratitude for their sacrifices to science. Without rodents, many breakthroughs would not have been possible.
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+David Andrews yeah I know but I think that's cool how he is stitching DNA 😃
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The barcodes on your boarding pass, it turns out, have quite a lot of information -- enough for someone who gets their hands on one to not only find your contact information, but get access to your flight itinerary, all your future flight itineraries, and more. A big part of the flaw is that many airlines seem to treat your frequent flyer number as a kind of password with respect to their sites -- if you know a name and number, you have access to everything and can modify everything as well -- but that number is sprayed pretty widely everywhere else, not least in this bar code.

So as a basic precaution, you probably want to treat airplane tickets like sensitive PII and shred them, not throw them out; but the more fundamental problems about security with airlines are something they have to fix. 
The next time you're thinking of throwing away a used boarding pass with a barcode on it, consider tossing the boarding pass into a document shredder instead. Two-dimensional barcodes and QR codes can hold a great deal of information, and the codes printed on airline boarding passes may allow ...
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Wait...  should I worry about my PII on my boarding pass before or after I put my check in my unlocked bag with all of my valuables on an international flight out of New Delhi?

Security is a charade...
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  • Stanford University
    Ph. D., Physics, 2003
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    B. A., Mathematics, Physics, 1997
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Chief Architect, Google+
Lots of people ask me what my job title means. I'm the senior engineer on the Google+ team, and my primary responsibility is to oversee and guide the technical design of Google+ and all of the things related to it. In practice, I'm also involved in lots of non-technical issues as well: my job is to make Google as fun, exciting, social, and pleasant a place to be as it can possibly be.

(I've been at Google since 2003, but you probably haven't seen me before this, because I worked deep in the back end: planet-scale storage, very large-scale search, ranking, and so on. Lots of teams whose unofficial motto is "if we told you, we'd have to kill you" -- as opposed to Google+, where we get to go out and talk and interact with our users.)

For those who just came here, welcome to the Google+ Project. It's something that we're all very passionate about, and which (as its name indicates) is going to continue to develop and improve at what we hope is an amazing rate. I'm avidly interested in hearing user feedback, and while I can't guarantee that I'll have time to respond to all of it, it will most certainly be listened to.

And the obligatory (very important!) disclaimer: I'm not on this system as an official representative. While I'm listening to user feedback and interacting about the system, I'm also here for perfectly ordinary social networking purposes. If I am saying something official on behalf of Google, I will make that explicitly clear; anything else that I say here is not the position of Google, or of anyone other than myself.

In fact, most of what I post about has nothing to do with CS at all. If you want a taste of it, take a look at my blog.
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