Slides from keynote at the Social News on the Web Workshop. Rio de Janeiro, Brazil, May 2013.

New Scientist 2914, 23 April 2013 (free registration required) describes our proyect

... A big problem with theories floated on social media is that information can go viral simply because it is popular, whether or not it is true. Patrick Meier of the Qatar Computing Research Institute (QCRI) in Doha is building Verily, a system that allows users to submit verification requests for information they are interested in. Each request prompts a crowd of online workers to set off into their networks to figure it out. The system gathers evidence for and against the claim, though it won't pass judgement.

...By training machine learning algorithms on huge data sets, Meier is building up profiles of the classes of digital evidence that tend to be credible, and those that are not.

As an example, Meier points to a recent study of misinformation on Twitter after the 2010 Chilean earthquake. Carlos Castillo of the QCRI and colleagues showed that non-credible tweets tend to spark responses that question or rebuke them – a trait software can be trained to recognise. "Non-credible information propagates across the twittersphere leaving very specific ripples behind," says Meier. "You could absolutely start having a probability – a percentage chance that particular tweets are not credible."

Full article in New Scientist (free registration required) »

I am glad to announce the third edition of the Web Quality workshop, to be held on May 13th, 2013 in Rio de Janeiro, Brazil. The workshop is co-located with the World Wide Web conference.

This year's theme is the question: Signal or Noise?. The Web and social media keep on growing and playing an ever increasing role in our lives. In this context, finding relevant, timely and trustworthy content in a sea of seemingly irrelevant chatter remains a challenging research issue.

The workshop will bring together practitioner and researchers working on key problem areas such as modelling trust and author reputation, detecting abuse and spam, finding high-quality content, uncovering plagiarism, among other topics.

Website: WebQuality 2013 » writes about our upcoming study on Internet Research extending our findings presented in "Information Credibility on Twitter" [pdf].

Social media hoaxes: Could machine-learning algorithms help debunk Twitter rumors before they spread?


In a new paper, to be published in the journal Internet Research next month, the authors of the Chile earthquake study—Carlos Castillo, Marcelo Mendoza, and Barbara Poblete—test out their algorithm on fresh data sets and find that it works pretty well. According to Meier, their machine-learning classifier had an AUC, or “area under the curve,” of 0.86. That means that, when presented with a random false tweet and a random true tweet, it would assess the true tweet as more credible 86 percent of the time. (An AUC of 1 is perfect; an AUC of 0.5 is no better than random chance.)

My guess is that a knowledgeable and experienced human Twitter user could do better than that under most circumstances. And of course, if a given algorithm became widespread, committed trolls like the Hurricane Sandy villain @ComfortablySmug could find ways to game it. Still, an algorithm has the potential to work much faster than a human, and as it improves, it could evolve into an invaluable "first opinion" for flagging news items on Twitter that might not be true.



Somebody told us you can find fresh vegetables and plants in Qatar directly from a producer that has lots of greenhouses. It is possible.

The place is worth a visit for a chance of seeing so much vegetation in such a dry place. Plants here are much cheaper than the price of the ones you find in the shopping malls. There is also a small selection of vegetables (the minimum you have to buy is one kilogram) that varies with the season.


We went on a Saturday morning and they closed around 12:30. I don't know what are the opening times in other days. You can only pay in cash.

How to get there:

The place is named "Arab Qatari Agricultural Co." the entrance is at these coordinates: 25.36681, 51.24544.

View Larger Map

Take Al Rayyan road towards the west. Continue on the highway to Dukhan past Education City on your left. Then you will pass a palace on your left, the Amiri guard on your left, then a large roundabout with a stadium (Al Rayyan Sports Club) on your right.

The next roundabout (a few kilometers ahead) is marked with signs for the Camel Racing tracks. Exit on that roundabout and immediately turn right, entering a road that goes back to Doha parallel to the highway and very close to it. Pass a Woqod petrol station on your left. Then you will find on your left the Arab Qatari place. There is a barrier there.

Ask them if they sell plants, they will say yes and open the barrier. Go inside, buy your plants and veggies, keep the receipts (they will ask for them on the way back), and enjoy!

Fotos: Foursquare, Fabiola.


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