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The Open-Source Data Science Masters - Curriculum

The Internet is Your Oyster

I didn't want to wait. I wanted to work on things I care about now. Why sleep through grad school lectures tomorrow when you can hack on interesting questions today?

see my transcript

With Coursera, ebooks, stackoverflow, and github -- all free and open -- how can you afford not to take advantage of an open source education?

The Motivation

We need more Data Scientists.

-- McKinsey Report Highlights the Impending Data Scientist Shortage 23 July 2013

-- David Hardtke How To Hire A Data Scientist 13 Nov 2012

An Academic Shortfall

Classic academic conduits aren't providing Data Scientists -- this talent gap will be closed differently.

-- James Kobielus, Closing the Talent Gap 17 Jan 2013

Ready?

The Open Source Data Science Curriculum

Start here.

• Intro to Data ScienceUW / Coursera
  • Topics: Python NLP on Twitter API, Distributed Computing Paradigm, MapReduce/Hadoop & Pig Script, SQL/NoSQL, Relational Algebra, Experiment design, Statistics, Graphs, Amazon EC2, Visualization.

Math

Computing

• Algorithms

• Databases

• Data Mining

• Machine Learning

• Probabilistic Graphical Models

• Natural Language Processing

• Analysis

• Python (Learning)

• Python (Libraries)

• R (Learning)

• R (Libraries)

• Natural Language Toolkit OpenNLP
• Text Mining [tm](http://cran.r-project.org/web/packages/tm/index.html]
• Basic Viz wordcloud
• Network Modeling & Viz igraph
• Basic Machine Learning e1071
• Kernel Method kernlab
• Chinese Language Processing Rwordseg
• Chinese Weibo Analysis Rweibo

Capstone Project

Further Study Resources:

A Note About Direction

This is an introduction geared toward those with at least a minimum understanding of programming, and (perhaps obviously) an interest in the components of Data Science (like statistics and distributed computing). Out of personal preference and need for focus, I geared the original curriculum toward Python tools and resources, so I've explicitly marked when resources use other tools to teach conceptual material (like R)

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It struck me that 2014 marks 25 years since the programming language Tcl (Tool Command Language) escaped from John Ousterhout's lab at UC Berkeley and was unleashed on the world. I think that's a milestone worth recognizing, and indeed celebrating.

For anyone under 40 years old, you can think of Tcl like Ruby or Python, if those languages didn't have objects, if absolutely everything in them was treated as a string, and if every syntax rule added to the language resulted in its creator being tortured for one year.

Assignments? Math? We don't need no special syntax for those! What in any other language would be written as "a=b+c" in Tcl would be:

In other words, Tcl as a language is what would happen if Lisp and csh met at a party, got way too drunk, hooked up, got pregnant, and kept drinking throughout the pregnancy.

And this is coming from a fan of the language.

Why was Tcl important?

John created Tcl as a scripting language to be embedded in other applications, so that each didn't create its own shitty configuration language from scratch. He also created a desktop graphical user interface toolkit for it, called Tk. Surprisingly, especially for John, people took his little add-on language and began creating substantial programs with it... no matter how much he begged them to stop. And because it was incredibly easy to hook up to C code, soon just about everything that had a C API soon had a Tcl API. Or ten.

For most people though, myself included, Tk was the real selling point. This was a time when most of the innovative programmers were working on Unix-based systems running X11. Back then, doing a "Hello World" program in X11 was hundreds of lines of code, but Tcl and Tk reduced it to just one:

Tcl and Tk took off with the cool kids in the early-mid 90's, peaked around 2000, and interest gradually eroded since then. It had its share of successes and controversies (if you want some historical entertainment, Google "Why you should not use Tcl"), organizational transitions and missed opportunities (did you know that Tcl almost became Javascript?). You can find more at the Tcl history page at www.tcl.tk.

Lasting influence

Despite the ridiculous syntax, Tcl did a ton of things right, well ahead of its time. The internal code quality has always been top-notch, and backed up by a rich automated testing suite. The complex implementation details of two language development, scripting, language extensions, and how to manage backwards compatibility and deployment in that kind of dynamic environment were greatly refined by Tcl over the years. Very early versions aside, Tcl was also wicked fast, I18N-savvy, and cross-platform.

While there's not a lot of new projects started with Tcl anymore, there's still a whole lot of legacy code out there, both scripts and applications written in Tcl, and all kinds of programs that have Tcl embedded inside them.

And of course, lots of other languages borrowed ideas and code from Tcl. Most notable is Tk, which became the defacto standard desktop GUI for just about every other scripting language, including those still in common use today such as Python (tkinter), Ruby (RubyTk), and Perl (Tkx).

Tcl was after all designed as a language to be embedded in other programs, so it's only slightly perverse to think that even other programming languages embed a Tcl interpreter.

And while desktop user interfaces have largely been supplanted by the web or mobile platforms, you'd be surprised how many people are still plugging away with Tk (whether from Tcl, Python, Ruby or some other language).

It's just one data point, but this site (TkDocs.com), which provides relatively up-to-date cross-language documentation on how to use the more modern features in Tk, gets over 10,000 unique visitors each month, and a Python-specific ebook version of the material (Modern Tkinter) still sells 50+ copies a month.

Standing on the Shoulders of Giants

A skit I wrote a few years back tackles the question of Is Tcl/Tk Dying Out?. But old programming languages never really die, they just tend to stagnate over time.

In the tech industry we're often too quick to throw things out and ignore lessons from the past. It's nice to know that some of the great ideas, principles, and yes, even code from Tcl continue to be built on even today. And there's still a core group of people slowly but surely working on the language itself.

So, 25 years after the beast was released, I just wanted to say thanks to the many thousands of people who contributed their time and energy over the years.

Cheers!

LONDON—Nicole Vloeimans, a 31-year-old worker at an NGO, lives in the very center of this expensive city. She has a 755-square-foot floor to herself. She pays £389 a month, about $635.

"I don't really know what to do with the space," says Ms. Vloeimans. "I don't have that much furniture."

There are some hitches. No parties are allowed. She needs permission to go on vacation. There is a hole in the kitchen ceiling. She had to paint over a swath of graffiti. The four-week notice to move out can come any time.

But so great is the demand for a reasonable flat that Londoners like Ms. Vloeimans are lining up to live in empty office buildings.

London's housing market is soaring. The average price for a home in the capital was £396,646 in November, Land Registry data show. The average rent for a one-bedroom apartment in central London was £1,368 in the 12 months ending in September, according to data from the U.K. government's Valuation Office Agency.

The boom has attracted growing throngs to a cheaper option: being a guardian.

Ms. Vloeimans's home is an abandoned office building once inhabited by squatters ("WE CALL IT EVOLUTION, U CALL IT A CRIME" reads graffiti in her kitchen). Squatters were evicted from her building last January. In exchange for the discounted rent, Ms. Vloeimans is meant to keep them from coming back.

The need for guardians is in part a consequence of Britain's peculiar laws on squatting. It isn't a crime to squat in an empty nonresidential building. It is a crime to remove a squatter without a lengthy civil-eviction court procedure.

So developers looking to rehab—or tear down—a building will fill it with guardians to keep the squatters away before work begins. The presence of guardians is often enough to deter squatters, because it is illegal to squat in an occupied building.

John Durkin, 55, lives in an old police station overlooking the River Thames. The condominiums next door sell to celebrities for around £2 million. He pays £450 a month.

"It's like being 17 years old, and your father tells you that he has a flat in London. 'And if you don't tell your mother, I'll let you keep it,' " said Mr. Durkin, a psychologist.

The living room has Wi-Fi and a stunning view, but his bedroom overlooking the train tracks has no electricity, meaning no heating. "I'm OK with a cold nose," he said.

Squatters were kicked out of an old brick building near Liverpool Street Station, one of London's main train hubs, in August. The front door opens to warped flooring, one dusty table, stained chairs, drums, a keyboard and amplifiers. A brown couch with yellow stuffing sprouting from its back sits against the front windows.

"They've done it up nice. You should have seen it before," said Arthur Duke, owner of Live-In Guardians, which supplies guardians for building owners. This place, at £250 a month, sits far below the usual properties he takes on.

Becoming a guardian isn't easy. "Demand is just out of control," said Mr. Duke. Live-In Guardians has about 2,000 people on its waiting list—by far the biggest backlog he has had since starting the business in 2009, he said. When a new property comes along, says Mr. Duke, 50 people will come to the open house.

Hip neighborhoods go fast. "If we put a property up on the website in Hackney, it's gone in five minutes," said Zoe Oakes of Ad Hoc, one of the largest guardian firms in London.

Guardian companies, which have guardians' fees as a source of revenue, tout themselves as cheaper alternatives to traditional security firms. Guardians need to be employed full time and can be subject to background checks.

In the city's gentrifying East End sits an "unremarkable three-story brick clad building" for light industry firms, according to a 2011 document of design plans. The building is set to be torn down. Meantime, guardians live there.

Oreste Noda, 46, is a Cuban percussionist. After moving into the building two years ago, his massive apartment became a hub for jam sessions.

"People would just come up from the street and be like, 'Man, this is great, what's the name of this club?' " said Michael Angelov, who lives in the same building. "I'd have to tell them it isn't a club, it's a home."

Mr. Angelov, a 31-year-old filmmaker, lives with his girlfriend in what he reckons was a media company's office. It is clean and has hardwood floors, nice desks and sofas.

His two bedrooms have glass walls. When friends stay over, "they're a bit like, 'What's this?' " he said. "But when it's just me and my girlfriend, it's fun."

For London's young professionals, guarding is a respectable alternative to squatting. Sam Golden, 24, who works in public relations, says he learned about property guardians from a longtime squatter—who was griping about capitalists edging in on squatters' turf.

Mr. Golden signed up with Guardians of London. Squatting "was on the fringes of the law, which is not viable for young professionals," he said. Now he lives in a once-empty building, one tube stop away from Wembley Stadium.

Other than having to take two days off work to clean the place, which included clearing a dead pigeon off one of the two pool tables, "it worked out perfectly."

Guardians do occasionally have to do some guarding. Once, the front door of a building in the southern city of Brighton managed by Oaksure Property Protection was smashed. Guardian Andrew Faley, 26, heard the sound and went down at 5 a.m. to check it out. He called it in to Oaksure's owners, and the door was fixed, he said.

Mark Ovenden, 50, has five oak-paneled rooms overlooking a central-London park. The bedroom is "about as big as any flat in Paris," said Mr. Ovenden, who lived in the French capital for six years. In the office Mr. Ovenden, a freelance television producer, has a wall-size world map detailing locations of major oil wells—a perk left over from an oil brokerage.

Getting around parts of the building without electricity requires light from his iPhone's flash. His two bathroom sinks lack hot water. And like all guardians, Mr. Ovenden is well aware that his time in the large, centrally located apartment for a discounted rent is fleeting. "I know we'll get moved out eventually. I'm prepared to make some sacrifices."

Write to Art Patnaude at art.patnaude@wsj.com

I had just moved to Singapore when I met the brilliant Benjamin Joffe (@benjaminjoffe) - a startup consultant and investor from France, who has spent the last 13 years living around Asia: a few years each in Korea, China, and Japan.

I asked him if he could tell me the most important thing he learned from living in these different countries.

He said, “Even though we are all using English as a common language, the same word can mean very different things in different places.”

I looked confused, so he said, “When I say the word ‘quality’, what do you think it means?”

I thought and said, “Quality means it works. It’s well-built. It will last.”

He beamed a big smile and said, “Exactly! I knew you were going to say that, because you’re American! If you ask almost any American what ‘quality’ means, they’ll say ‘it works’. To you, that’s the definition of the word, but it’s actually just the American definition of the word.

“In Korea, if I ask almost anyone what quality means, they’ll say, ‘it’s brand new’. In Korea, newness is important. Don’t go to Korea trying to emphasize the timeless long-lasting quality of your product. What matters is what’s new.

“In Japan, if I ask almost anyone what quality means, they’ll say, ‘it’s perfect - zero defects’. Japanese culture emphasizes the importance of striving for perfection. I saw a company ship a huge box of their products to Japan, but the shipment was not accepted because the shipping container was dented. Although the items inside were fine, it was no longer a ‘quality’ shipment, since it was no longer perfect.

“In China, if I ask almost anyone what quality means, they’ll say, ‘it gives status’. Guanxi is everything - your standing in a personal network - so any item that gives you social status is considered quality. It doesn’t matter if it’s well-built or will last, as long as it raises your social status.”

He waited while I digested this thought.

Then he said, “This is why you can’t just take your brilliant American business idea and go make it happen in China, India, or Indonesia. ‘Quality’ is just one word, but imagine the different cultural meanings of words like ‘music’, ‘romantic’, ‘friends’, or even ‘fun’!”

This conversation is a big reason I started my Wood Egg book series. Understanding the different mindsets of different cultures has interested me ever since, so it’s fun to keep diving deeper and deeper into the subject.

Later, I asked a Singaporean friend why high-tech always-online Singapore has almost no online shopping.

He said, “Shopping is something you go out and do with your friends! A few companies have tried to popularize online shopping in Singapore, but it has never worked.”

When I explained how it would save people a lot of time and money to being able to buy anything at home, without having to go out to the mall, he smiled and said, “What if I came to America and tried to start a company that helped people stay at home and get drunk alone, while sitting at their computer, so that they didn’t need to go out to bars with friends anymore? Wouldn’t that save them a lot of time and money?”

Touché.

Click any book cover, below, to jump to the page for it.

There was a time when the word "supercomputer" inspired the same sort of giddy awe that infuses Superman or Superconducting Supercollider. A supercomputer could leap tall buildings in a single bound and peer into the secrets of the universe. 

And chief among this race of almost mythical machines was the Cray. Seymour Cray's first computer, the Cray 1, debuted in 1976, and was the embodiment of all the power that crackled around the supercomputer. It weighed 10,500 pounds. Thirty humans were necessary to help install it. And its first users built nuclear weapons: Model No. 1 went to Los Alamos National Laboratory. Eventually Cray sold 80. 

I love this description of its capabilities and style from the National Center for Atmospheric Research (which got Cray's third machine):

One megabyte of memory! 80 million computations per second! Current smartphones blow away that kind of performance.

But still, there's something to the Cray.

And so, as GigaOm reports, two hobbyists,  Chris Fenton and Andras Tantos, decided to try to recreate the machine, but at desktop scale.

The physical form was relatively easy to put together. They used a CNC machine, painted the wood model, and covered the "semicircle" with pleather. The hardware was easy to get a hold of, too.

"It wasn’t difficult to find a board option that could handle emulating the original Cray computational architecture. Fenton settled on the $225 Spartan 3E-1600, which is tiny enough to fit in a drawer built into the bench," GigaOm writes. "Considering the first Crays cost between $5 and 8 million, that’s a pretty impressive bargain."

The thing that turned out to be tricky, actually, was the software. No one had preserved a copy of the Cray operating system. Not the Computer History Museum. Not the U.S. government. It was just gone. 

Fenton searched high and low, eventually finding an old disc pack that contained a later version of the Cray OS. Restoring the software to usable condition proved a ridiculously ornate task, which Tantos, a Microsoft engineer took over. And, after a year of work, they're finally getting somewhere:

For them and for us, this should serve as a reminder that computing eats its own history. The Cray was the supercomputer, and not a single historian or archivist can show you the working object itself.

Luckily, the world has nerds like Chris Fenton and Andras Tantos. Thanks.

JACEY

This is a warning. Please read carefully.

By now you've probably seen a Predictor; millions of them have been sold by the time you're reading this. For those who haven't seen one, it's a small device, like a remote for opening your car door. Its only features are a button and a big green LED. The light flashes if you press the button. Specifically, the light flashes one second before you press the button.

Most people say that when they first try it, it feels like they're playing a strange game, one where the goal is to press the button after seeing the flash, and it's easy to play. But when you try to break the rules, you find that you can't. If you try to press the button without having seen a flash, the flash immediately appears, and no matter how fast you move, you never push the button until a second has elapsed. If you wait for the flash, intending to keep from pressing the button afterwards, the flash never appears. No matter what you do, the light always precedes the button press. There's no way to fool a Predictor.

The heart of each Predictor is a circuit with a negative time delay — it sends a signal back in time. The full implications of the technology will become apparent later, when negative delays of greater than a second are achieved, but that's not what this warning is about. The immediate problem is that Predictors demonstrate that there's no such thing as free will.

There have always been arguments showing that free will is an illusion, some based on hard physics, others based on pure logic. Most people agree these arguments are irrefutable, but no one ever really accepts the conclusion. The experience of having free will is too powerful for an argument to overrule. What it takes is a demonstration, and that's what a Predictor provides.

Typically, a person plays with a Predictor compulsively for several days, showing it to friends, trying various schemes to outwit the device. The person may appear to lose interest in it, but no one can forget what it means — over the following weeks, the implications of an immutable future sink in. Some people, realizing that their choices don't matter, refuse to make any choices at all. Like a legion of Bartleby the Scriveners, they no longer engage in spontaneous action. Eventually, a third of those who play with a Predictor must be hospitalized because they won't feed themselves. The end state is akinetic mutism, a kind of waking coma. They'll track motion with their eyes, and change position occasionally, but nothing more. The ability to move remains, but the motivation is gone.

Before people started playing with Predictors, akinetic mutism was very rare, a result of damage to the anterior cingulate region of the brain. Now it spreads like a cognitive plague. People used to speculate about a thought that destroys the thinker, some unspeakable lovecraftian horror, or a Gödel sentence that crashes the human logical system. It turns out that the disabling thought is one that we've all encountered: the idea that free will doesn't exist. It just wasn't harmful until you believed it.

Doctors try arguing with the patients while they still respond to conversation. We had all been living happy, active lives before, they reason, and we hadn't had free will then either. Why should anything change? "No action you took last month was any more freely chosen than one you take today," a doctor might say. "You can still behave that way now." The patients invariably respond, "But now I know." And some of them never say anything again.

Some will argue that the fact the Predictor causes this change in behaviour means that we do have free will. An automaton cannot become discouraged, only a free-thinking entity can. The fact that some individuals descend into akinetic mutism whereas others do not just highlights the importance of making a choice.

Unfortunately, such reasoning is faulty: every form of behaviour is compatible with determinism. One dynamic system might fall into a basin of attraction and wind up at a fixed point, whereas another exhibits chaotic behaviour indefinitely, but both are completely deterministic.

I'm transmitting this warning to you from just over a year in your future: it's the first lengthy message received when circuits with negative delays in the megasecond range are used to build communication devices. Other messages will follow, addressing other issues. My message to you is this: pretend that you have free will. It's essential that you behave as if your decisions matter, even though you know that they don't. The reality isn't important: what's important is your belief, and believing the lie is the only way to avoid a waking coma. Civilization now depends on self-deception. Perhaps it always has.

And yet I know that, because free will is an illusion, it's all predetermined who will descend into akinetic mutism and who won't. There's nothing anyone can do about it — you can't choose the effect the Predictor has on you. Some of you will succumb and some of you won't, and my sending this warning won't alter those proportions. So why did I do it?

Because I had no choice.

Microsoft today announced it will continue to provide updates to its security products (antimalware engine and signatures) for Windows XP users through July 14, 2015. Previously, the company said it would halt all updates on the same day as the end of support date for Windows XP: April 8, 2014.

For consumers, this means Microsoft Security Essentials will continue to get updates after support ends for Windows XP. For enterprise customers, the same goes for System Center Endpoint Protection, Forefront Client Security, Forefront Endpoint Protection, and Windows Intune running on Windows XP.

Here is the previous guidance from a page Microsoft had set up specifically to discuss Windows XP end of support:

The company is thus providing updates to its security products for an additional 15 months. In other words, while Windows XP will no longer be a supported operating system come April, companies will be at least partially protected (the actual OS still won’t get security updates) until next July.

Microsoft is in a tricky situation. On the one hand, it needs to push consumers and businesses off of Windows XP to more secure products, and the best way to do that is to stick to its end of support date. On the other hand, there are still so many millions of Windows XP users out there that leaving them completely vulnerable could cause more harm than good.

The company thus says its research shows “that the effectiveness of antimalware solutions on out-of-support operating systems is limited” and offers the following advice:

• Use modern software that has advanced security technologies and is supported with regular security updates.
• Regularly apply security updates for all software installed.
• Run up-to-date anti-virus software.

Windows XP is over 12 years old so if you’re still on it, only the third point still applies, and that’s just because Microsoft is bending over backwards for you. It’s time to move on.

See also – Windows 8 and Windows 8.1 pass 10% market share, Windows XP falls below 30% and Windows 8.1 overtakes Windows XP on Steam

Top Image Credit: Kevin Lee/Getty Images

15 January 2014

Two months have passed since I posted aninitial benchmark of the Rust and C++ implementations of Cap'n Proto. Enough has changed in that time to make it worth presenting updated results.

One change is that I got a faster computer. Unfortunately, that means that results from the two benchmarks will not be directly comparable.

A more pertinent change is that I (partially) implemented scratch-space reuse, an optional feature that can reduce allocations. The addition of this feature doubles the number of benchmark configurations, as we can run each communication mode with or without "reuse" turned on.

Otherwise, the benchmark itself is the same as before.

First, the "carsales" case, heavy on numbers.

Recall that in November's benchmark, capnproto-rust was slightly faster than capnproto-c++ in "object" mode. This is no longer true. I believe that capnproto-c++ was previously disadvantaged because it was providing extra thread safety—in particular, the ability for multiple threads to share a mutable MessageBuilder. That feature was dropped in this commit.

Next, the "catrank" case, heavy on strings.

In November, capnproto-rust was hampered here by its lack of support for direct writing of string fields. That has been remedied. However, capnproto-rust has another disadvantage here; cpu profiling reveals that it spends roughly ten percent of its time verifying that strings are valid UTF-8, while capnproto-c++ does not bother with any such verification. Note that the Cap'n Proto encoding spec requires that strings be valid UTF-8, but says nothing about whether the receiver of a non-UTF-8 string should report an error.

Finally, the "eval" case, heavy on pointer indirections.

In contrast to November's results, the relative performance of capnproto-rust now does not significantly degrade when it must perform I/O in the "pipe" communication mode. The main reason for the improvement is that the benchmark now uses libnative, Rust's 1:1 threading runtime, whereas in November it used libgreen, Rust's M:N threading runtime built on libuv. Only recently has it become convenient to swap between these two runtimes. If I run the "eval" case in "pipe" mode with libgreen today, Rust takes approximately twice as long as it does with libnative.

PAJU, South Korea — At the base of a mountain almost two miles from the North Korean border, the giant helium balloons slowly float upward, borne by a stiff, cold wind. These are not balloons in the conventional sense—the transparent, cylindrical tubes covered in colorful Korean script are more than 20 feet in length and each carries three large bundles wrapped in plastic. The characters painted on one of the balloons reads, “The regime must fall.”

The launch site is at the confluence of the Imjin and Han Rivers, which form the border with North Korea. From here, it’s possible to see the Potemkin village constructed on the shores across the river. The picturesque agrarian hamlet is really just a series of uninhabited sham structures, which contrast sharply with the bustle and industry of the South Korean side. Using binoculars we can see people “walking” back and forth and pretending to till the land despite below-freezing temperatures.

We’re here to hack the North Korean government’s monopoly of information above the 38th parallel on the Korean peninsula. The North Korean dictatorship continues to be one of the most totalitarian regimes on the planet. While other regimes oppress their dissidents and censor the Internet, North Korea has no dissidents and no connection to the outside world. It has no Internet. The Kim family rules with absolute authority, arbitrarily imprisoning or executing anyone who stands in their way. The regime goes even further; not only is the offender imprisoned, but entire generations of his family are also sent to the gulags. The embargo of information into and out of the country has forced human rights groups to be creative in their methods of reaching North Korean citizens.

The balloons rise and drift toward the border dividing democratic South Korea and Kim Jong Un’s totalitarian regime in the north. Each balloon carries a bundle containing DVDs, USBs, transistor radios, and tens of thousands of leaflets printed with information about the world outside North Korea. Once the balloons travel far enough north, a small timer will break open the sturdy plastic bags and shower the contents of the packages over the countryside. The text printed on the leaflets is changed from launch to launch; the leaflets we are using today contain a cartoon depicting Kim Jong Un’s execution of his uncle as well as pro-democracy and human rights literature. 

In preparation for Wednesday’s launch, a group of tireless men and women, most defectors themselves, put together the precious cargo the balloons carry. This group is part of an organization called Fighters for a Free North Korea, and their leader is Park Sang Hak, a defector and son of a former North Korean spy who escaped 15 years ago by swimming across the river. Park has since dedicated his life to fighting for freedom in his homeland. That dedication has earned him awards (he received the Human Rights Foundation’s Václav Havel Prize for Creative Dissent last year) as well as attempts on his life.

In 2011, a North Korean assassin traveled to Seoul and tried to kill Park with a poison needle hidden inside a pen. The South Korean National Intelligence Service found out about the plan to murder Park, whom the Pyongyang regime has designated “Enemy Zero,” and tipped him off before he went to meet the would-be killer.

Undaunted, Park continued his efforts to offer support to the countrymen he had left behind. He realized that although the government tightly controlled everything that came into the country on the ground, the sky remained free. Park decided this would be his way of smuggling his message across the border.

This is how we found ourselves at a mountaintop an hour and a half outside of Seoul in 15-degree-Fahrenheit weather. We had been preparing for weeks in secret in order to stay off the South Korean government’s radar, after our previous launch attempt was thwarted by South Korean police forces.

In June of last year, at a different border site, word got out about the effort, which was to be the first time that a foreign NGO had collaborated directly in such an activity. Two days before the anticipated launch date, the North Korean government issued a warning through its propaganda outlet, threatening, “[I]f you so much as haunt [the launch site] with your presence and act as human shields for refugees who have already been sentenced to death, we will kill you.”

We chose to ignore this inflammatory rhetoric, which is typical of the regime, and pressed on. The morning of the launch, however, the North Korean government issued a second warning, this time from the Command of the Korean People’s Army, saying the launch "reminds one of a puppy knowing no fear of a tiger." This threat was taken so seriously by the South Korean government that its security forces mobilized to stop us.

On the day of the launch, 300 uniformed South Korean policemen swarmed the site, preventing us from achieving our goal. Park attempted to drive to another launch site, but he was stopped and taken to a nearby police station, where he was detained for six hours and then released. The episode underlined how many South Koreans regard the human rights struggle in the North as merely a distraction and an annoyance.

So what do these balloons carry that is dangerous enough to the North Korean government to warrant an attempted assassination and multiple public death threats to an international NGO? All of the goods carried by the balloons are illegal inside North Korea, but the regime consistently names one item in their threats to Park and his group: the pro-democracy leaflets.

The North Korean government dreads subversive information. For decades, the regime has controlled all information entering the country. While the government still has a monopoly over information dissemination within North Korea, cracks are beginning to show. Many North Koreans now have access to smuggled DVDs and USBs loaded with videos. They are seeing the world outside the North, and it doesn’t match up to the dictatorship’s lies and propaganda. Shows such as Desperate Housewives and The Mentalist, and films like Bad Boys, all of which defectors tell us are very popular in the North, provide a wildly different alternative to their daily lives.

Slowly, piercing the information blockade is helping to expose the fallibility of the North Korean state. Kim Jong Un’s government, just like the governments of his father and grandfather before him, is engineered to make North Korean citizens dependent on the state for everything. However, the famine of the 1990s, in which over a million North Koreans starved to death, forced people to depend less on the state for survival. The black market, fueled by smuggling, began to gain momentum.

Smuggling is the only way to bring information and technology to the North Korean people, and it is punishable by death. DVDs, USBs, and even laptops are making their way over the Chinese border into the hands of North Koreans, helped along by NGOs based in South Korea. Some groups engage directly in smuggling activities to provide information and equipment, others use short- and medium-wave radio broadcasts, and Park Sang Hak uses balloons and other creative methods of sending help over the border.

These groups, however, are in the midst of a crisis. Finding support, especially for the more aggressive methods, is difficult within South Korea, as South Koreans fear antagonizing their distant relatives in the North. Until this year, the U.S. government provided support for these groups through the National Endowment for Democracy and the State Department’s DRL programs. The majority of this funding however, has been cut in the last year. A remarkable opportunity now exists, given the funding gap, to build peer-to-peer networks between Korean defectors and worldwide allies willing to stand against despotism. Radio transmission is especially costly, and one group we visited in Seoul won’t be able to afford to produce its programming after March of this year.

These groups struggle in silence as the international press creates a media circus around Dennis Rodman and his “friendship” with Kim Jong Un. His antics feed into the popular perception of the regime as a bizarre place where bad things happen as opposed to one of the world’s cruelest tyrannies, being challenged by a handful of civil society organizations with combined annual budgets totaling no more than $1 million. And the North, with its nuclear hardware, concentration camps, and totalitarian control over its people, is being challenged with freedom of expression and the power of ideas. In the end, we believe ideas will win. 

3 years ago, we published a report on 2011 Facebook Demographics & Statistics that covered gender, location, education, and more (US only). Recently we dove into Facebook’s Social Advertising platform to get a refreshed snapshot of the same data points to see what exactly has happened over time and to look at the numbers behind many recent claims: teenagers are leaving by the millions. Enjoy!

Top Insights:

1) Teens (13-17) on Facebook have declined -25.3% over the last 3 years.

2) Over the same period of time, 55+ (perhaps those teens’ parents and grandparents?) have exploded with +80.4% growth in the last 3 years.

3) Of the major metropolitan areas, San Francisco saw the highest growth with +148.6%, a stark contrast with Houston which saw +23.8% growth.

We also took a closer look at the Teens (13-17 year olds) and the Folks (55+) to get a better understanding of their current representation on Facebook. Here you go:

UPDATE — Thanks for all the feedback and comments on this post, here’s a quick clarification:

Many have commented on the fact that “Teens” (age 13-17 in this post) as we recorded in 2011 have now grown into the 18-24 year old demographic. While that’s true, the primary point of this post was simply to draw attention to the fact that Facebook’s Social Advertising platform shows 3 million fewer addressable 13-17 year olds today compared to 2011.

By Jonathan Stempel

Tue Jan 14, 2014 8:55pm EST

The 9th U.S. Circuit Court of Appeals late on Tuesday let stand an order by U.S. District Judge Lucy Koh in San Jose, California to let the workers sue as a group, and pursue what the defendants said could exceed $9 billion of damages.

The case began in 2011 when five software engineers sued Apple, Google, Adobe Systems Inc, Intel Corp and others over an alleged "overarching conspiracy" to suppress pay by agreeing not to recruit or hire each other's employees.

These defendants were accused of violating the Sherman Act and Clayton Act antitrust laws by conspiring to eliminate competition for labor, depriving workers of job mobility and hundreds of millions of dollars in compensation.

Class certification can make it easier for plaintiffs to extract larger awards, at lower cost than if they sued individually. It could also add pressure on defendants to settle.

"We look forward to seeking justice for the class at trial," said Kelly Dermody, a partner at Lieff, Cabraser, Heimann & Bernstein, co-lead counsel for the class. She said a trial is set to begin on May 27.

A Google spokesman declined to comment. An Intel spokesman had no immediate comment. Adobe and Apple did not immediately respond to requests for comment.

In seeking the appeal, the companies had called Koh's order "manifestly erroneous".

They said that the claims were too disparate because they covered employees with 2,400 job titles at seven companies, and that the plaintiffs did not allege any impact on total hiring.

The U.S. Chamber of Commerce also asked the 9th Circuit to grant permission for the appeal.

Much of the case was built on emails between top officials, including the late Apple Chief Executive Steve Jobs and former Google Chief Executive Eric Schmidt, that the plaintiffs said reflected understandings not to raid each other's talent.

The 9th Circuit decision is Hariharan et al v. Adobe Systems Inc et al, 9th U.S. Circuit Court of Appeals, No. 13-80223. The lower-court case is In re: High-Tech Employee Antitrust Litigation, U.S. District Court, Northern District of California, No. 11-02509.

After a decade of exploring the Martian surface, the scientists overseeing veteran rover Opportunity thought they’d seen it all. That was until a rock mysteriously “appeared” a few feet in front of the six wheeled rover a few days ago.

News of the errant rock was announced by NASA Mars Exploration Rover lead scientist Steve Squyres of Cornell University at a special NASA Jet Propulsion Laboratory “10 years of roving Mars” event at the California Institute of Technology (Caltech), Pasadena, Calif., on Thursday night. The science star-studded public event was held in celebration of the decade since twin rovers Spirit and Opportunity landed on the Red Planet in January 2004.

PHOTOS: Alien Robots That Left Their Mark on Mars

While chronicling the scientific discoveries made by both rovers over the years, Squyres discussed the recent finding of suspected gypsum near the rim of Endeavour Crater— a region of Meridiani Planum that Opportunity has been studying since 2011 — and the discovery of clays that likely formed in a pH-neutral wet environment in Mars past. While these discoveries have been nothing short of groundbreaking, Squyres shared the Mars rover’s team’s excitement for that one strange rock, exclaiming: “Mars keeps throwing new stuff at us!”

In a comparison of recent photographs captured by the rover’s panoramic camera, or Pancam, on sol 3528 of the mission, only bare bedrock can be seen. But on sol 3540, a fist-sized rock had appeared (raw Pancam images can be found in the mission archive). MER scientists promptly nicknamed the object “Pinnacle Island.”

“It’s about the size of a jelly doughnut,” Squyres told Discovery News. “It was a total surprise, we were like ‘wait a second, that wasn’t there before, it can’t be right. Oh my god! It wasn’t there before!’ We were absolutely startled.”

But the rover didn’t roll over that area, so where did Pinnacle Island come from?

Only two options have so far been identified as the rock’s source: 1) The rover either “flipped” the object as it maneuvered or, 2) it landed there, right in front of the rover, after a nearby meteorite impact event. The impact ejecta theory, however, is the least likely of the two.

“So my best guess for this rock … is that it’s something that was nearby,” said Squyres. “I must stress that I’m guessing now, but I think it happened when the rover did a turn in place a meter or two from where this rock now lies.”

Opportunity’s front right steering actuator has stopped working, so Squyres identified that as the possible culprit behind the whole mystery.

Each wheel on the rover has its own actuator. Should an actuator jam or otherwise fail, the robot’s mobility can suffer. In the case of this wheel, it can no longer turn left or right. “So if you do a turn in place on bedrock,” continued Squyres, “as you turn that wheel across the rock, it’s gonna kinda ‘chatter.’” This jittery motion across the bedrock may have propelled the rock out of place, “tiddlywinking” the object from its location and flipping it a few feet away from the rover.

NEWS: Opportunity Finds More Hints of Mars Habitability

Never missing a scientific opportunity, Opportunity scientists hope to study the bright rock. “It obligingly turned upside down, so we’re seeing a side that hasn’t seen the Martian atmosphere in billions of years and there it is for us to investigate. It’s just a stroke of luck,” he said.

“You think of Mars as being a very static place and I don’t think there’s a smoking hole nearby so it’s not a bit of crater ejecta, I think it’s something that we did … we flung it.”

Although this is the leading theory behind the case of the random rock, Squyres pointed out that the investigation is still under way and it will be a few days before his team can definitively say where Pinnacle Island came from.

Opportunity has outlived its 3-month primary mission by ten years, notching up nearly 23 miles on the odometer so far. Sister rover Spirit succumbed to the Martian elements in 2009 when it became stuck in a sand trap in Gusev Crater. Spirit’s mission was declared lost when it stopped transmitting in March 2010, likely drained of energy. Although Spirit had the rougher time on Mars and was the first to die, it was also a huge success, aiding our understanding of of Mars’ geological history and outliving its warranty by 5 years. But now it’s just Opportunity and Mars’ new arrival Curiosity that soldier on to reveal more than we ever dreamed about our neighboring Red Planet.

As the NASA Jet Propulsion Laboratory rover drivers, scientists and engineers recounted stories of their beloved robots on Thursday, it became very clear that they aren't just machines of discovery, they are family.

The President delivers remarks at the Department of Justice presenting the outcomes of the Administration's review of U.S. signals intelligence programs. He focus on steps that increase oversight and transparency while leaving the framework of the surveillance programs in place.  In addition, he will turn to Congress for guidance regarding the future of NSA data collection.

The President’s Review Group on Intelligence and Communications Technologies recommended more than 40 suggested changes at the NSA in a wide-ranging report issued this past December. Administration officials say Obama is likely to embrace many of the recommendations.

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