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Carsten Führmann
Such a big playground, so little time.
Such a big playground, so little time.

Carsten's posts

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(via +Hartmut Noack) A viral Twitter trend about the questionable practice of whiteboard job interviews. Top performers from the industry confess how they would fail at tasks to which the applicants are subjected.

I was subjected to a whiteboard interview once, my only failed job interview ever. I was asked to find bugs in a ugly peace of computer code, in a language I could have learned within a week. (My PhD and academic work were in programming language design!) I failed to do it on the spot and wasn't hired.

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They do things differently in California: San José Councilman Lan Diep takes his oath with a Captain America shield. This really made my day.
As an Atheist, I really like what our new councilman, Lan Diep, did. You don't need to swear on a holy book to assure everyone that you will do your best and be truthful. This is awesome :D

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How curious!
350,000 robots tweet about Star Wars

Many Twitter users aren't real people. For example, there's a network of 350,000 accounts that did nothing but automatically post tweets about Star Wars novels. It's called the Star Wars botnet. It appeared in 2013. Then it went quiet. it was discovered only recently. Nobody knows why it exists.

It was found recently - almost by accident! Two cybersecurity researchers at University College London downloaded data about 6 million English-speaking Twitter accounts. That's about 1% of the total number.

They found something bizarre, shown on the map here.

Twitter lets you quickly download the most recent 3,200 tweets of any user, along with geo-tags that are supposed to say where the tweets came from. This let the researchers map the locations of all the tweets they downloaded. As you'd expect, most tweets came from densely populated regions - with a distribution nicely matching the population distribution.

But they also found 23,000 tweets that were geo-located in uninhabited regions - like deserts and oceans! And when they plotted these locations, they fit neatly into two precise rectangles, one around the U.S. and the other around Europe!

Conclusion: these tweets came from bots randomly choosing locations in the two rectangles.

They looked through the 3,000 accounts that created these tweets. None of these accounts had ever published more than 11 tweets. They never had more than 10 followers. They never had fewer than 31 friends. They were all produced by Twitter for Windows phones.

But here's the real giveaway: they all contained random quotations from Star Wars novels - with hashtags inserted at random. A typical example:

Luke’s answer was to put on an extra burst of speed. There were only ten meters #separating them now.

Quoting from Technology Review:

At this point, Echeverria and Zhou conjectured that they had stumbled across a single botnet, presumably controlled by a single botmaster. This botnet was obviously large since 3,000 bots had appeared in a random search. And that raised an obvious question: just how big was this botnet?

To find out, the researchers trained a machine-learning algorithm to recognize Star Wars bots and set it loose on a much larger database of 14 million English-speaking Twitter users.

The results were a shock. The machine-learning algorithm, with the help of some manual filtering, found some 350,000 accounts that had the same characteristics. These accounts had never tweeted more than 11 times, had fewer than 31 friends and were all produced by Twitter for Windows Phone.

What’s more, this entire botnet was created in just a few days in June and July 2013. At the time, it produced 150,000 tweets a day.

Then it stopped. “When the creation of new Star Wars bots stopped on 14 July 2013, all the bots suddenly fell silent and remained so ever since,” say Echeverria and Zhou.

But the accounts have not been closed down or deleted. They could all tweet at a moment’s notice, should the botmaster so decide. Echeverria and Zhou say the bots have avoided detection because they were deliberately designed to keep a low profile. “It seems the Star Wars bots were deliberately designed to circumvent many of the heuristics underlying previous bot detection methods,” say Echeverria and Zhou.

Echeverria and Zhou conjecture that perhaps this botnet will be sold at some time... and spring into action.

Since then, they've found an even larger botnet, with 500,000 accounts!

So: beware of fake news, trolls, and zombies.

Read more here:

• Cybersecurity experts uncover dormant botnet of 350,000 Twitter accounts, Technology Review, 20 January 2017,

and read the original paper here:

• Juan Echeverría and Shi Zhou, The “Star Wars” botnet with >350k Twitter bots,

Thanks to +Jan Galkowski for pointing this out!

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+Frau M​​ and I enjoyed the most amazing concert last night, by the composer/performer Rebecca Trescher and her Ensemble 11. In the first half, they played pieces from their amazing last album "Fields", and in the second half they moved on to a stunning new suite called "Floating Food". The latter, if I understood correctly, will soon be recorded as an album at the "Bayerischer Rundfunk".

It's a rather unconventional 11-head band: besides instruments typical for Jazz, it also involves a cello, a transverse flute, a harp, and a rather unusual voice artist. (The harpist and vibraphonist are unfortunately invisible in the picture.) The sound just blew me away.

In case anyone is interested, their last couple of CDs are these:

Ensemble 11:

By a previous 5-head band:

The picture was taken by +Frau M​.


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Behold the decoration of our window sill!

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The news outlet of the future Counselor of the US President has struck again.

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Hiking around the Achensee in Austria. It was one of the shortest days of the year, but at times it felt like summer in the Mediterranean.
5 Photos - View album

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I just backed this kickstarter project to save climate data. Better safe than sorry. 
Give the Earth a present: help us save climate data

We've been busy backing up climate data before Trump becomes President. Now you can help too, with some money to pay for servers and storage space.   Please give what you can at our Kickstarter campaign here:

If we get $5000 by the end of January, we can save this data until we convince bigger organizations to take over.   If we don't get that much, we get nothing.  That's how Kickstarter works.   Also, if you donate now, you won't be billed until January 31st.

So, please help!   It's urgent.

I will make public how we spend this money.  And if we get more than $5000, I'll make sure it's put to good use.  There's a lot of work we could do to make sure the data is authenticated, made easily accessible, and so on.

The idea

The safety of US government climate data is at risk. Trump plans to have climate change deniers running every agency concerned with climate change.  So, scientists are rushing to back up the many climate databases held by US government agencies before he takes office.

We hope he won't be rash enough to delete these precious records. But: better safe than sorry!

The Azimuth Climate Data Backup Project is part of this effort. So far our volunteers have backed up nearly 1 terabyte of climate data from NASA and other agencies. We'll do a lot more!  We just need some funds to pay for storage space and a server until larger institutions take over this task.

The team

+Jan Galkowski is a statistician with a strong interest in climate science. He works at Akamai Technologies, a company responsible for serving at least 15% of all web traffic. He began downloading climate data on the 11th of December.

• Shortly thereafter +John Baez, a mathematician and science blogger at U. C. Riverside, joined in to publicize the project. He’d already founded an organization called the Azimuth Project, which helps scientists and engineers cooperate on environmental issues.

• When Jan started running out of storage space, +Scott Maxwell  jumped in. He used to work for NASA — driving a Mars rover among other things — and now he works for Google. He set up a 10-terabyte account on Google Drive and started backing up data himself.

• A couple of days later +Sakari Maaranen joined the team. He’s a systems architect at Ubisecure, a Finnish firm, with access to a high-bandwidth connection. He set up a server, he's downloading lots of data, he showed us how to authenticate it with SHA-256 hashes, and he's managing many other technical aspects of this project.

There are other people involved too.  You can watch the nitty-gritty details of our progress here:

Azimuth Backup Project - Issue Tracker:

and you can learn more here:

Azimuth Climate Data Backup Project.


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That sums it up nicely. (Via +Andreas Eschbach)

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Wie eine anständige Zeitung mit dem Attentat umgeht, und wie Bild-Zeitung es tut. Via +Kristof Zerbe​​​​. (Good vs. terrible media coverage about the terror attack in Berlin.)
Treffender kann man es nicht gegenüberstellen. BILD ist der beste Verbündete der Terroristen.

(aus, via +Silja Sch)
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