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Concordia University
Montréal, Canada

On GATE, Text Analysis, Summarisation, Linked Data and Mining Social Media

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Posts about our text and social media analysis work and latest news on GATE ( - our open source text and social media analysis platform. Also posts about the PHEME project ( and our work on automatic detection of rumours in social media. Lately also general musings about fake news, misinformation, and online propaganda.
Updated: 19 hours 25 min ago

Funded PhD Opportunity: Large Scale Analysis of Online Disinformation in Political Debates

Tue, 2018-04-24 18:38
Applications are invited for an EPSRC-funded studentship at The University of Sheffield commencing on 1 October 2018.
The PhD project will examine the intersection of online political debates and misinformation, through big data analysis. This research is very timely, because online mis- and disinformation is reinforcing the formation of polarised partisan camps, sharing biased, self-reinforcing content. This is coupled with the rise in post-truth politics, where key arguments are repeated continuously, even when proven untrue by journalists or independent experts. Journalists and media have tried to counter this through fact-checking initiatives, but these are currently mostly manual, and thus not scalable to big data.

The aim is to develop machine learning-based methods for large-scale analysis of online misinformation and its role in political debates on online social platforms.

Application deadline: 5pm, Friday 18 May 2018  
Interviews: interviews will take place week commencing 4 June 2018

Supervisory team: Professor Kalina Bontcheva (Department of Computer Science, University of Sheffield), Professor Piers Robinson (Department of Journalism, University of Sheffield), and Dr. Nikolaos Aletras (Information School, University of Sheffield).

Award DetailsThe studentship will commence on 1 October 2018. The studentship will cover tuition fees at the EU/UK rate and provide an annual maintenance stipend at standard Research Council rates (£14,777 in 2018/19) for 3.5 years.
EligibilityThe general eligibility requirements are:
  • Applicants should normally have studied in a relevant field to a very good standard at MSc level or equivalent experience.
  • Applicants should also have a 2.1 in a BSc degree, or equivalent qualification, in a related discipline.
  • ESRPC studentships are only available to students from the UK or European Union. Applications cannot be accepted from students liable to pay fees at the Overseas rate. Normally UK students will be eligible for a full award which pays fees and a maintenance grant if they meet the residency criteria and EU students will be eligible for a fees-only award, unless they have been resident in the UK for 3 years immediately prior to taking up the award.
How to applyTo apply for the studentship, applicants need to apply directly to the University of Sheffield for entrance into the doctoral programme in Computer Science 

  • Complete an application for admission to the standard computer science PhD programme 
  • Applications should include a research proposal; CV; academic writing sample; transcripts and two references.
  • The research proposal of up to 1,000 words should outline your reasons for applying to this project and how you would approach the research including details of your skills and experience in both computing and/or data journalism.
  • Supporting documents should be uploaded to your application.
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Discerning Truth in the Age of Ubiquitous Disinformation (5): Impact of Russia-linked Misinformation vs Impact of False Claims Made By Politicians During the Referendum Campaign

Sun, 2018-04-08 13:56
Discerning Truth in the Age of Ubiquitous Disinformation (5)Impact of Russia-linked Misinformation vs Impact of False Claims Made By Politicians During the Referendum Campaign
Kalina Bontcheva (@kbontcheva)

My previous post focuses mainly on the impact of misinformation from Russian Twitter accounts.  However it is important to also acknowledge the impact of false claims made by politicians which were shared and distributed through social media.

A House of Commons Treasury Committee Report published on May 2016, states that: “The public debate is being poorly served by inconsistent, unqualified and, in some cases, misleading claims and counter-claims. Members of both the ‘leave’ and ‘remain’ camps are making such claims. Another aim of this report is to assess the accuracy of some of these claims..”

In our research, we analysed the number of Twitter posts around some of the these disputed claims, firstly to understand their resonance with voters, and secondly, to compare this to the volume of Russia-related tweets discussed above.

A study  of the news coverage of the EU Referendum campaign established that the economy was the most covered issue, and in particular, the Remain claim that Brexit would cost households £4,300 per year by 2030 and the Leave campaign’s claim that the EU cost the UK £350 million each week. Therefore, we focused on  these two key claims and analysed tweets about them.

With respect to the disputed £4,300 claim (made by the Chancellor of the Exchequer), we  identified 2,404 posts in our dataset (tweets, retweets, replies), referring to this claim.

For the £350 million a week disputed claim - there are 32,755 pre-referendum posts (tweets, retweets, replies) in our dataset. This is 4.6 times the 7,103 posts related to Russia Today and Sputnik and 10.2 times more than the 3,200 tweets by the Russia-linked accounts suspended by Twitter.

In particular, there are more than 1,500 tweets from different voters, with one of these wordings:

I am with @Vote_leave because we should stop sending £350 million per week to Brussels, and spend our money on our NHS instead.

I just voted to leave the EU by postal vote! Stop sending our tax money to Europe, spend it on the NHS instead! #VoteLeave #EUreferendum

Many of those tweets have themselves received over a hundred likes and retweets each.

This false claim is being regarded by media as one of the key ones behind the success of VoteLeave.

So returning to Q27 on likely impact of misinformation on voting behaviour - it was not possible for us to quantify this from such tweets alone. A potentially useful indicator comes from an Ipsos Mori poll published on 22 Jun 2016, which  showed that for 9% of respondents the NHS was the most important issue in the campaign.

In conclusion, while it is important to quantify the potential impact of Russian misinformation, we should also consider the much wider range of misinformation that was posted on Twitter and Facebook during the referendum and its likely overall impact.

We should also study not just fake news sites and the social platforms that were used to disseminate misinformation, but also the role and impact of Facebook-based algorithms for micro-targeting adverts, that have been developed by private third parties.

A related question, is studying the role played by hyperpartisan and mainstream media sites during the referendum campaign. This is the subject of our latest study, with key findings available here
High Automation Accounts in Our Brexit Tweet Dataset

While it is hard to quantify all different kinds of fake accounts, we know already that a study by City University identified 13,493 suspected bot accounts, amongst which Twitter found only 1% as being linked to Russia. In our referendum tweet dataset there are tweets by 1,808,031 users in total, which makes the City bot accounts only 0.74% of the total.

If we consider in particular, Twitter accounts that have posted more than 50 times a day (considered high automation accounts by researchers), then there are only 457 such users in the month leading up to the referendum on 3 June 2016.

The most prolific were "ivoteleave" and "ivotestay", both suspended, which were similar in usage pattern. There were also a lot of accounts that did not really seem to post much about Brexit but were using the hashtags in order to get attention for commercial reasons.

We also analysed the leaning of these 457 high automation accounts an identified 361 as pro-leave (with 1,048,919 tweets), 39 pro-remain (156,331 tweets), and the remaining 57 as undecided.

I covered how we can address the “fake news” problem in me previous blog post (link) but in summary we need to promote fact checking efforts, and fund open-source research on automatic methods for disinformation detection.

Disclaimer: All views are my own.

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Discerning Truth in the Age of Ubiquitous Disinformation (4): Russian Involvement in the Referendum and the Impact of Social Media Misinformation on Voting Behaviour

Sun, 2018-04-08 13:55
Discerning Truth in the Age of Ubiquitous Disinformation (4)Russian Involvement in the Referendum and the Impact of Social Media Misinformation on Voting Behaviour
Kalina Bontcheva (@kbontcheva)

In my previous blog posts I wrote about the 4Ps of the modern disinformation age: post-truth politics, online propaganda, polarised crowds,  and partisan media; and how we can combat online disinformation

The news is currently full of reports of Russian involvement in the referendum and the potential impact of social media misinformation on voting behaviour

A small scale experiment by the Guardian exposed 10 US voters (five on each side) to  alternative Facebook news feeds. Only one participant changed his mind as to how they would vote. Some found their confirmation bias too hard to overcome, while others became acutely aware of being the target of abuse, racism, and misogyny.  A few started empathising with voters holding opposing views. They also gained awareness of the fact that opposing views abound on Facebook, but the platform is filtering them out. 

Russian Involvement in the Referendum
We analysed the accounts that were identified by Twitter as being associated with Russia in front of the US Congress in the fall of 2017, and we also took the other 45 ones that we found with BuzzFeed. We looked at tweets posted by these accounts one month before the referendum, and we did not find an awful lot of activity when compared to the overall number of tweets on the referendum, i.e. both the Russia-linked ads and Twitter accounts did not have major influence. 

There were 3,200 tweets in our data sets coming from those accounts, and 800 of those—about 26%—came from the new 45 accounts that we identified. However, one important aspect that has to be mentioned is that those 45 new accounts were tweeting in German, so even though they are there, the likely impact of those 800 tweets on the British voter is, I would say, not very likely to have been significant.

The accounts that tweeted on 23 Jun were quite different from those that tweeted before or after, with virtually all tweets posted in German. Their behaviour is also very different - with mostly retweets on referendum day by a tight network of anti-Merkel accounts, often within seconds of each other. The findings are in line with those of Prof. Cram from the University of Edinburgh, as reported in the Guardian

Journalists from BuzzFeed UK and our Sheffield  team  used the re-tweet  network to identify another 45 suspicious accounts, subsequently suspended by Twitter. Amongst the 3,200 total tweets, 830 came from the 45 newly identified accounts (26%).  Similar to those identified by Twitter, the newly discovered accounts were largely ineffective in skewing public debate. They attracted very few likes and retweets – the most successful message in the sample got just 15 retweets.

An important distinction that needs to be made is between Russia-influenced accounts that used advertising on one hand, and the Russia-related bots found by Twitter and other researchers on the other. 

The Twitter sockpuppet/bot accounts generally pretended to be authentic people (mostly American, some German) and would not resort to advertising, but instead try to go viral or gain prominence through interactions. An example of one such successful account/cyborg is Jenn_Abrams. Here are some details on how the account duped mainstream media: 

“and illustrates how Russian talking points can seep into American mainstream media without even a single dollar spent on advertising.” 

A related question is the influence of Russia-sponsored media and its Twitter posts. Here we consider the Russia Today promoted tweets - the 3 pre-referendum ones attracted just 53 likes and 52 retweets between them.

We analysed all tweets posted one month before 23 June 2016, which are either authored by Russia Today or Sputnik, or are retweets of these. This gives an indication of how much activity and engagement there was around these accounts. To put these numbers in context, we also included the equivalent statistics for the two main pro-leave and pro-remain Twitter accounts:

Account Original tweets Retweeted by others Retweets by this account Replies by account Total tweets @RT_com -  General Russia Today 39 2,080 times 62 0 2,181 @RTUKnews 78 2,547 times 28 1 2,654 @SputnikInt 148 1,810 times 3 2 1,963 @SputnikNewsUK 87 206 times 8 4 305 TOTAL 352 6,643 101 7 7,103

@Vote_leave 2,313 231,243 1,399 11 234,966 @StrongerIn 2,462 132,201 910 7 135,580

We also analysed which accounts retweeted RT_com and RTUKnews the most in our dataset. The top one with 75 retweets of Russia Today tweets was a self-declared US-based account that retweets Alex Jones from infowars, RT_com, China Xynhua News, Al Jazeera, and an Iranian news account. This account (still live) joined in Feb 2009 and as of 15 December 2017 has 1.09 million tweets - this means an average of more than 300 tweets per day, indicating it is a highly automated account. It has more than 4k followers, but follows only 33 accounts. Two of the next most active retweeters are a deleted and a suspended account, as well as two accounts that both stopped tweeting on 18 Sep 2016. 

For the two Sputnik accounts, the top retweeter made 65 retweets. It declares itself as Ireland based; has 63.7k tweets and 19.6k likes; many self-authored tweets; last active on 2 May 2017; account created on May 2015; avg 87 tweets a day (which possibly indicates an automated account);. It also retweeted Russia Today 15 times. The next two Sputnik retweeters (61 and 59 retweets respectively) are accounts with high average post-per-day rate (350 and 1,000 respectively) and over 11k and 2k followers respectively. Lastly, four of the top 10 accounts have been suspended or deleted. 

Disclaimer: All views are my own.
Categories: Blogroll

Discerning Truth in the Age of Ubiquitous Disinformation (3): The Role of News Media

Sat, 2018-03-10 14:18
Discerning Truth in the Age of Ubiquitous Disinformation (3)The Role of News Media
Kalina Bontcheva (@kbontcheva)

Post coming soon

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Thu, 2018-03-08 13:33
Discerning Truth in the Age of Ubiquitous Disinformation (2)How Can We Combat Online Disinformation

Kalina Bontcheva (@kbontcheva)

In my previous blog post I wrote about the 4Ps of the modern disinformation age: post-truth politics, online propaganda, polarised crowds,  and partisan media. 
Now, let me reflect some more on the question of what can we do about it. Please note that this is not an exhaustive list!Promote Collaborative Fact Checking Efforts In order to counter subjectivity, post-truth politics, disinformation, and propaganda, many media and non-partisan institutions worldwide have started fact checking initiatives – 114 in total, according to Poynter. These mostly focus on exposing disinformation in political discourse, but generally aim at encouraging people to pursue accuracy and veracity of information (e.g. Politifact,, Snopes). A study by the American Press Institute has shown that even politically literate consumers benefit from fact-checking as they increase their knowledge of the subject.Professional fact checking is a time-consuming process that cannot cover a significant proportion of the claims being propagated via social media channels. To date, most projects have been limited to one or two steps of the fact checking process, or are specialized on certain subject domains: Claimbuster, ContentCheck and the ongoing Fake News Challenge are a few examples. There are two ways to lower the overheads and I believe both are worth pursuing: 1) create a coordinated fact-checking initiative that promotes collaboration between different media organisations, journalists, and NGOs; 2) fund the creation of automation tools for analysing disinformation, to help the human effort.  I discuss the latter in more detail next.
Fund open-source research on automatic methods for disinformation detection In the PHEME research project we focused specifically on studying rumours associated with different types of events—some were events like shootings and others were rumours and hoax stories like “Prince is going to have a concert in Toronto”—and how those stories were disseminated via Twitter or Reddit. We looked at how reliably we can identify such rumours: one of the hardest tasks is how to group all the different social media posts like tweets or Reddit posts around the same rumour together. In Reddit it is a bit easier thanks to threads. Twitter is harder because often there are multiple originating tweets that refer to the same rumour.
That is the real challenge: to piece together all these stories, because the ability to identify whether something is correct or not depends a lot on evidence and also on the discussions around that rumour, that the public are carrying out on social media platforms. By seeing one or two tweets, sometimes even journalists cannot be certain whether a rumour is true or false, but as we see the discussion around the rumours and the accumulating evidence over time, the judgment becomes more reliable.
Consequently,  it becomes easier to predict the veracity of a rumour, but the main challenge is identifying reliably all these different tweets that are talking about the same rumour. If sufficient evidence can be provided across different tweet posts, it becomes possible to determine the veracity of that rumour with around 85% accuracy.
In the wider context, there is emerging technology for veracity checking and verification of social media content (going beyond images/video forensics). These include tools developed in several European projects (e.g. PHEME, REVEAL, and InVID), tools assisting crowdsourced verification (e.g. CheckDesk,, citizen journalism (e.g. Citizen Desk), and repositories of checked facts/rumours (e.g. Emergent, FactCheck). However, many of those tools are language specific and would thus need adaptation and enhancement to new languages. Besides, further improvements are needed to the algorithms themselves, in order to achieve accuracy comparable to that of email spam filter technology. 
It is also important to invest in establishing ethical protocols and research methodologies, since social media content raises a number of privacy, ethical, and legal challenges. 
Dangers and pitfalls of relying purely on automated tools for disinformation detection Many researchers (myself included) are working on automated methods based on machine learning algorithms, in order to identify automatically disinformation on social media platforms. Given the extremely large volume of  social media posts, key questions are can disinformation be identified in real time and should such methods be adopted by the social media platforms themselves?The very short answer is: Yes, in principle, but we are still far from solving many key socio-technical issues, so, when it comes to containing the spread of disinformation, we should be mindful of the problems which such technology could introduce: l      Non-trivial scalability: While some of our algorithms work in near real time on specific datasets such as tweets about the Brexit referendum - applying them across all posts on all topics as Twitter would need to do, for example, is very far from trivial. Just to give a sense of the scale here - prior to 23 June 2016 (referendum day) we had to process fewer than 50 Brexit-related tweets per second, which was doable. Twitter, however, would need to process more than 6,000 tweets per second, which is a serious software engineering, computational, and algorithmic challenge.l      Algorithms make mistakes, so while 90 per cent accuracy intuitively sounds very promising, we must not forget the errors - 10 per cent in this case, or double that at 80 per cent algorithm accuracy. On 6,000 tweets per second this 10 per cent amounts to 600 wrongly labeled tweets per second rising to 1,200 for the lower accuracy algorithm. To make matters worse, automatic disinformation analysis often combines more than one algorithm - first to determine which story a post refers to and second - whether this is likely true, false, or uncertain. Unfortunately, when algorithms are executed in a sequence, errors have a cumulative effect.l      These mistakes can be very costly: broadly speaking algorithms make two kinds of errors - false negatives in which disinformation is wrongly labelled as true or bot accounts wrongly identified as human and false positives, correct information is wrongly labelled as disinformation or genuine users being wrongly identified as bots. False negatives are a problem on social platforms, because the high volume and velocity of social posts (e.g. 6,000 tweets per second on average) still leaves  with a lot of disinformation “in the wild”. If we draw an analogy with email spam - even though most of it is filtered out automatically, we are still receiving a significant proportion of spam messages. False positives, on the other hand, pose an even more significant problem, as falsely removing genuine messages is effectively censorship through artificial intelligence. Facebook, for example, has a growing problem with some users having their accounts wrongly suspended.Therefore, I strongly believe that the best way forward is to implement human-in-the-loop solutions, where people are assisted by machine learning and AI methods, but not replaced entirely, as accuracy is still not high enough, but primarily, for the censorship danger.
Establishing Cooperation and Data Exchange between Social Platforms and ScientistsOur latest work on analysing misinformation in tweets about the UK referendum [1] [2]  showed yet again a very important issue - when it comes to social media and furthering our ability to understand its misuse and impact on society and democracy, the only way forward is for data scientists, political and social scientists and journalists to work together alongside the big social media platforms and policy makers. I believe data scientists and journalists need to be given open access to the full set of public social media posts on key political events for research purposes (without compromising privacy and data protection laws), and be able to work in collaboration with the platforms through grants and shared funding (such as the Google Digital News Initiative).
There are still many outstanding questions that need to be researched - most notably the dynamics of the interaction between all these Twitter accounts over time - for which we need the complete archive of public tweets, images, and URL content shared, as well as profile data and friend/follower networks. This would help us quantify better (amongst other things) what kinds of tweets and messages resulted in misinformation spreading accounts gaining followers and re-tweets, how human-like was the behaviour of the successful ones, and also were they connected to the alternative media ecosystem and how.
The intersection of automated accounts, political propaganda, and misinformation is a key area in need of further investigation, but for which, scientists often lack the much needed data, while the data keepers lack the necessary transparency, motivation to investigate these issues, and willingness to create open and unbiased algorithms.
Policy Decisions around Preserving Important Social Media Content for Future StudiesGovernments and policy makers are in a position to help establish this much needed cooperation between social platforms and scientists, promote the definition of policies for ethical, privacy-preserving research and data analytics over social media data, and also ensure the archiving and preservation of social media content of key historical value. For instance, given the ongoing debate on the scale and influence of Russian propaganda on election and referenda outcomes, it would have been invaluable to have Twitter archives made available to researchers under strict access and code of practice criteria, so it becomes possible to study these questions in more depth. Unfortunately, this is not currently possible, with Twitter having suspended all Russia-linked accounts and bots, as well as all their content and social network information. Similar issues arise when trying to study online abuse of and from politicians, as posts and accounts are again suspended or deleted at a very high rate. Related to this is the challenge of open and repeatable science on social media data, as again many of the posts in current datasets available for training and evaluating machine learning algorithms, have been deleted or are not available. This causes a problem as algorithms do not have sufficient data to improve as a result and neither can scientists determine easily whether a new method is really outperforming the state-of-the-art. Promoting Media Literacy and Critical Thinking for Citizens
According to the Media Literacy project: “Media literacy is the ability to access, analyze, evaluate, and create media. Media literate youth and adults are better able to understand the complex messages we receive from television, radio, Internet, newspapers, magazines, books, billboards, video games, music, and all other forms of media.”
Training citizens in the ability to recognise spin, bias, and mis- and disinformation are key elements. Due to the extensive online and social media exposure of children, there are also initiatives aimed specifically at school children, starting from as young as 11 years old. There are also online educational resources on media literacy and fake news [3], [4] that could act as a useful starting point of national media literacy initiatives.
Increasingly, media literacy and critical thinking are seen as key tools in fighting the effects of online disinformation and propaganda techniques [5], [6]. Many of the existing programmes today are delivered by NGOs in a face-to-face group setting. The next challenge is how to roll these out at scale and also online, in order to reach wide audience across all social and age groups.
Establish/revise and enforce national code of practice for politicians and media outlets
Disinformation and biased content reporting are not just the preserve of fake news and state-driven propaganda sites  and social accounts. A significant amount also comes from partisan media and factually incorrect statements by prominent politicians.
In the case of the UK EU membership referendum, for example, a false claim regarding immigrants from Turkey was made on the front pages of a major UK newspaper [7], [8]. Another widely known and influential example was VoteLeave’s false claim that the EU costs £350 million a week [9]. Even though the UK Office of National Statistics disputed the accuracy of this claim on 21 April 2016 (2 months prior to the referendum), it continued to be used throughout the campaign.
Therefore, an effective way to combat deliberate online falsehoods must address such cases as well. Governments and policy makers could help again through establishing new or updating existing codes of practice of political parties and press standards, as well as ensuring that they are adhered to. 
These need to be supplemented with transparency in political advertising on social platforms, in order to eliminate  or significantly reduce promotion of misinformation through advertising. These measures would also help with reducing the impact of all other kinds of disinformation already discussed above.
Disclaimer: All views are my own.
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Students use GATE and Twitter to drive Lego robots

Tue, 2018-02-27 17:27

At the university's Headstart Summer School in July 2017, 42 students (age 16 and 17) from all over the UK were taught to write Java programs to control Lego robots, using input from the robots (such as the sensor for detecting coloured marks on the floor) as well as operating the motors to move and turn.  (The university provided a custom Java library for this.)

On 11 and 12 July we ran a practical session on "Controlling Robots with Tweets".  We presented a quick introduction to natural language processing (using computer programs to analyse human languages such as English) and provided them with a bundle of software containing a version of the GATE Cloud Twitter Collector modified to run a special GATE application with a custom plugin to let it use the Java robot library.

The bundle came with a simple "gazetteer" containing two lists of classified keywords:

and a basic JAPE grammar to make use of it.  JAPE is a specialized language used in GATE to match regular expressions over annotations in documents. (The annotations are similar to XML tags, except that GATE applications can create them as well as read them and they can overlap each other without restrictions.  Technically they form an annotation graph.)

The grammar we provided would match any keyword from the "turn" list followed by any keyword from the "left" list (with zero or more unmatched words in between, e.g., "turn to port", "take a left", "turn left") and then run the code to turn the robot's right motor (making it turn left in place).

We showed them how to configure the Twitter Collector, authenticate with their Twitter accounts, follow themselves, and then run the collector with this application.  Getting the system set up and working was a bit laborious, but once the first group got their robot to move in response to a tweet and cheered, everyone got a lot more interested very quickly.  They were very interested in extending the word lists and JAPE rules to cover a wider range of tweeted commands.

Some of the students had also developed interesting and complicated manoeuvres in Java the previous day, which they wanted to incorporate into the Twitter-controlled system.  We helped these students add their code to their own copies of the GATE plugin and re-load it so the JAPE rules could call their procedures.

This project was fun and interesting for the staff as well as the students, and we will include it in Headstart 2018.

The Headstart 2017 video includes these activities.  The instructions (presentation and handout) and software are available on-line.

This work is supported by the European Union's Horizon 2020 project SoBigData (grant agreement no. 654024).

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