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Sean Leather
Lives in Pretoria, South Africa
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Sean Leather

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The Appeals Court just told the Federal District Court judge to take his 485 pages and.... Good stuff!
The 4th U.S. Circuit Court of Appeals ruled against the state's law requiring voters to show photo identification. The court found that the Legislature had "discriminatory intent."
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Sean Leather

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Very interesting. I agree with most of what is written.

There are, of course, areas of science in which replication is prohibitively expensive (e.g. sending a probe out of the solar system) or just doesn't make sense (e.g. math, some CS). And replication would increase the cost of doing research. But the broad thesis of the article is attractive.
A few years ago, I became aware of serious problem in science: the irreproducibility crisis. A group of researchers at Amgen, an American…
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That still sounds like review and not replication to me. In the context of independent replication of experimental results, the replicating studies should themselves be peer-reviewed and published.

Each person that studies a proof is not going to publish a replication of that proof because it would be the exact same thing. However, you do find publications of counterproofs and improvements and simplifications of proofs (if they are significant enough), but these are not the same as replicating experiments.

Proofs involve logic. Experiments involve variables. The point of independent replication is to determine if an experiment produces results that are statistically similar to published results with a similar method and similar variables. A proof (that doesn't involve probability) will always be (in-)valid in a given logic. Even when using different logics, it can be interesting to compare proofs of one thing, but the differences are not statistically variable; therefore, I would not call it experimental replication.

Sean Leather

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This reads like an article from The Onion. But it's not satire.
There is simply no precedent for a presidential candidate publicly appealing to a foreign adversary to intervene in the election on his behalf.
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I’m an oft-time admirer of the words of Robert Reich, and never more strongly than recently. As one of the most vocal advocates for Bernie…
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Endorsed by Putin

Putin, eager to weaken the EU and NATO, has been backing right-wing demagogues throughout Europe.   So it came as no surprise when he started complimenting Trump.  Not only is Trump would-be strongman of Putin's ilk (only less clever), he's also been threatening to break US commitments to NATO.

In December, Putin called Trump "an outstanding and talented personality".  Trump, in a rare moment of sweetness, replied:

"It is always a great honor to be so nicely complimented by a man so highly respected within his own country and beyond."

Putin?  Respected?

Putin now appears to be backing Trump even more strongly, with Russian operatives hacking into Democratic National Committee (DNC) computers and trying to embarrass them shortly before the convention.

On June 14th, the cybersecurity firm CrowdStrike, under contract with the DNC, announced in a blog post that two separate Russian intelligence groups had gained access to the DNC network.  One, called FANCY BEAR or APT 28, gained access in April. The other, COZY BEAR or APT 29, first breached the network in the summer of 2015.

You can read a more detailed analysis here:

https://www.crowdstrike.com/blog/bears-midst-intrusion-democratic-national-committee/

Let me quote some:

CrowdStrike Services Inc., our Incident Response group, was called by the Democratic National Committee (DNC), the formal governing body for the US Democratic Party, to respond to a suspected breach. We deployed our IR team and technology and immediately identified two sophisticated adversaries on the network – COZY BEAR and FANCY BEAR. We’ve had lots of experience with both of these actors attempting to target our customers in the past and know them well. In fact, our team considers them some of the best adversaries out of all the numerous nation-state, criminal and hacktivist/terrorist groups we encounter on a daily basis. Their tradecraft is superb, operational security second to none and the extensive usage of ‘living-off-the-land’ techniques enables them to easily bypass many security solutions they encounter. In particular, we identified advanced methods consistent with nation-state level capabilities including deliberate targeting and ‘access management’ tradecraft – both groups were constantly going back into the environment to change out their implants, modify persistent methods, move to new Command & Control channels and perform other tasks to try to stay ahead of being detected. Both adversaries engage in extensive political and economic espionage for the benefit of the government of the Russian Federation and are believed to be closely linked to the Russian government’s powerful and highly capable intelligence services.

COZY BEAR (also referred to in some industry reports as CozyDuke or APT 29) is the adversary group that last year successfully infiltrated the unclassified networks of the White House, State Department, and US Joint Chiefs of Staff. In addition to the US government, they have targeted organizations across the Defense, Energy, Extractive, Financial, Insurance, Legal, Manufacturing Media, Think Tanks, Pharmaceutical, Research and Technology industries, along with Universities. Victims have also been observed in Western Europe, Brazil, China, Japan, Mexico, New Zealand, South Korea, Turkey and Central Asian countries. COZY BEAR’s preferred intrusion method is a broadly targeted spearphish campaign that typically includes web links to a malicious dropper. Once executed on the machine, the code will deliver one of a number of sophisticated Remote Access Tools (RATs), including AdobeARM, ATI-Agent, and MiniDionis. On many occasions, both the dropper and the payload will contain a range of techniques to ensure the sample is not being analyzed on a virtual machine, using a debugger, or located within a sandbox. They have extensive checks for the various security software that is installed on the system and their specific configurations. When specific versions are discovered that may cause issues for the RAT, it promptly exits. These actions demonstrate a well-resourced adversary with a thorough implant-testing regime that is highly attuned to slight configuration issues that may result in their detection, and which would cause them to deploy a different tool instead. The implants are highly configurable via encrypted configuration files, which allow the adversary to customize various components, including C2 servers, the list of initial tasks to carry out, persistence mechanisms, encryption keys and others. An HTTP protocol with encrypted payload is used for the Command & Control communication.

FANCY BEAR (also known as Sofacy or APT 28) is a separate Russian-based threat actor, which has been active since mid 2000s, and has been responsible for targeted intrusion campaigns against the Aerospace, Defense, Energy, Government and Media sectors. Their victims have been identified in the United States, Western Europe, Brazil, Canada, China, Georgia, Iran, Japan, Malaysia and South Korea. Extensive targeting of defense ministries and other military victims has been observed, the profile of which closely mirrors the strategic interests of the Russian government, and may indicate affiliation with Главное Разведывательное Управление (Main Intelligence Department) or GRU, Russia’s premier military intelligence service. This adversary has a wide range of implants at their disposal, which have been developed over the course of many years and include Sofacy, X-Agent, X-Tunnel, WinIDS, Foozer and DownRange droppers, and even malware for Linux, OSX, IOS, Android and Windows Phones. This group is known for its technique of registering domains that closely resemble domains of legitimate organizations they plan to target. Afterwards, they establish phishing sites on these domains that spoof the look and feel of the victim’s web-based email services in order to steal their credentials. FANCY BEAR has also been linked publicly to intrusions into the German Bundestag and France’s TV5 Monde TV station in April 2015.

At DNC, COZY BEAR intrusion has been identified going back to summer of 2015, while FANCY BEAR separately breached the network in April 2016. We have identified no collaboration between the two actors, or even an awareness of one by the other. Instead, we observed the two Russian espionage groups compromise the same systems and engage separately in the theft of identical credentials. While you would virtually never see Western intelligence agencies going after the same target without de-confliction for fear of compromising each other’s operations, in Russia this is not an uncommon scenario. “Putin’s Hydra: Inside Russia’s Intelligence Services”, a recent paper from European Council on Foreign Relations, does an excellent job outlining the highly adversarial relationship between Russia’s main intelligence services – Федеральная Служба Безопасности (FSB), the primary domestic intelligence agency but one with also significant external collection and ‘active measures’ remit, Служба Внешней Разведки (SVR), the primary foreign intelligence agency, and the aforementioned GRU. Not only do they have overlapping areas of responsibility, but also rarely share intelligence and even occasionally steal sources from each other and compromise operations. Thus, it is not surprising to see them engage in intrusions against the same victim, even when it may be a waste of resources and lead to the discovery and potential compromise of mutual operations.

You can even see some of the code that was used. Another security group, Fidelis, did an independent study confirming CrowdStriker's findings:

http://www.threatgeek.com/2016/06/dnc_update.html

Of course, none of this excuses the DNC's dastardly behavior as revealed by the hacked emails.  But it's another sign of how sickening a disaster a Trump presidency would be.

----------------------------------------------------------

Putin's compliment, and Trump's reply, is here:

http://www.cnn.com/2015/12/17/politics/russia-putin-trump/

Here's an article on Putin's "useful idiots" in Europe:

http://foreignpolicy.com/2016/02/23/why-europe-is-right-to-fear-putins-useful-idiots/

A quote, which contains lots of links in the original:

Prior to 2010, one would be hard-pressed to find public statements in praise of Putin by far-right leaders. Today, they are commonplace. UKIP’s Nigel Farage is a self-proclaimed fan of the Russian president. Jobbik’s head, Gabor Vona, is a frequent invited guest in Moscow. And, of course, Madame Le Pen, whose party was the beneficiary of a 9.4 million euro loan from a Russian-owned bank, is a consistent voice of support for Russian foreign policy in Ukraine and the Middle East. Even Germany, where the far right has failed to gain a foothold, is not immune to Moscow’s narrative. Supporters of PEGIDA, the increasingly popular xenophobic group whose acronym stands for “Patriotic Europeans Against the Islamization of the West,” often carry Russian flags and anti-government posters begging for Putin’s help.
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Sean Leather

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Whoa. Unexpected, perhaps not good timing, but needed to happen?
Some prominent Democrats had called for the Democratic National Committee chairwoman to step down in the wake of emails revealing the party’s attempts to undermine Bernie Sanders’s presidential bid.
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+Frank Atanassow I imagined the Russian hackers had some motive for it, but it didn't occur to me that Putin would prefer Trump and would attempt to hack an election like this. Granted, Putin does tend to revel in chaos, so it could fit his MO in a way. But I'm not sure I see all the angles and have a fair understanding of what actually happened. Maybe we'll find out more soon.

Sean Leather

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Nearly all of the New York Times columnists seem to have something to say about Trump. Seems like they forgot about the world outside the Republican National Convention.
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Sean Leather

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In 2002, I grew annoyed with not finding the obscure technical information I was looking for, so I started Gmane, the mailing list archive. All technical discussion took place on mailing lists thos…
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Sean Leather

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I've enjoyed the way that +Lena Groeger has put things into the perspective of (analytical) design. Defaults are a very important thing, and most people don't realize it. Actually, it's partially because people don't realize their importance that defaults are important. Also, people are naturally lazy/complicit.
The many ways we act by default (without even knowing it).
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Sean Leather

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Love the way +Alastair Reid​​ describes Verilog and EDA tools. It's so true that it's a different world from programming languages and compilers.
Part of the reason why the ISA-Formal technique for verifying ARM processors is so effective and so portable across different ARM processors is the fact that we directly use the ARM Instruction Set Architecture (ISA) Specification in our flow. That is, I translate ARM’s official printed documentation into something that I can load into a model checker alongside ARM’s processor Verilog and I verify that the two match each other.
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+Darshana Morar-Leather and I went on a hot-air balloon ride over the Hartbeespoort Dam on Friday. It was awesome.
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That's quite ingenious-and it's a great picture!

Sean Leather

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It was drawn to my attention that there is an active Reddit thread about the future of dependent types in Haskell. (Thanks for the heads up, @thomie!) Instead of writing a long response inline in R…
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+Alan Davidson Dependent types are an approach to increasing type safety. Haskell's type system already allows one to define a number of properties about data, but there are many things it can't do. For example, you can specify tree-like structure with a statically-unknown member type, but you can't statically determine the size of the structure. Having extra properties about your code and data means you can say more about its limits and prove that you stay within those limits. A proof of this sort – which is verified with the compiler's assistance and not by a fallible human alone – is more valuable than a typical unit test because the proof provides a guarantee while the test only adds confidence. (Alternatively stated, a proof provides 100% coverage for a particular case while a unit test is only as valuable as its inputs and is itself at risk of bugs.)

This is the standard motivation for dependent types. The specific motivation for dependent types in Haskell is that Haskell already has a large body of practical code and real-world programmers. In terms of academic research, this platform serves as a great experiment for trying dependently typed programming “in the wild.” Other dependently typed programming languages have either (a) been targeted primarily at niche academic communities or (b) have not been in development and use as long as Haskell and have not reached its scale of usage. So, it's exciting for research to see how dependent types can be implemented in a practical way, and it's exciting for Haskell programmers to have the ability to use them in practice.
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Utrecht, Netherlands - Austin, TX, USA - St. Louis, MO, USA - Chattanooga, TN, USA
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I'm a PhD student in Computer Science at Utrecht University in the Netherlands. I've been in school for most of my life. One of these days, I'll figure out what I'm going to do once I get out.
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Dependent types in Haskell: Progress Report
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It was drawn to my attention that there is an active Reddit thread about the future of dependent types in Haskell. (Thanks for the heads up,

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When I run brew upgrade in my Bash shell, it breaks the terminal display (in both iTerm2 and Terminal) such that I can't see anything I type

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Authoritative sources in the EU debate are thin on the ground, so I was pleased when a colleague pointed me to a video by University of Live

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This post is a response to ​Anthony's blog post about contributing to GHC, and the subsequent ​Reddit discussion. You'll find it easier to f

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Impressive large thatch-roofed lodge on the side of a mountain with a good view and a convenient location for visiting places around Haartebeespoort.
Public - a week ago
reviewed a week ago
Wonderful food and entertaining host. We had the Thuringian bratwurst and the prawns (not on the menu) for our main dishes and the apple strudel and chocolate mousse for dessert. The bratwurst was authentic German-style sausage: delicious. Mike, the owner, told us all kinds of stories. He is proud of his cooking, too. We would definitely go back again.
Public - a week ago
reviewed a week ago
Domino's pizza is better than Roman's, Debonairs, and Scooters.
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reviewed a week ago
A Food Lover's like every other.
Public - 2 weeks ago
reviewed 2 weeks ago
50 reviews
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It's kind of a nice place to take kids. You get to see and touch the cows. The food at the outdoor restaurant is okay but not that special. The farm shop has some nice local products.
Public - a week ago
reviewed a week ago
Nice shows. I've been to a couple, and they were pretty good. The visibility of the stage is good from both the floor and the balcony.
Public - a week ago
reviewed a week ago
This is a posh Spar with some nice high-market imports. The food at the cafe inside is nothing special.
Public - 2 weeks ago
reviewed 2 weeks ago