Shifting social opinions has far-reaching implications in various aspects, such as public health campaigns, product marketing, and political candidates. In this paper, we study a problem of opinion optimization based on the popular Friedkin-Johnsen (FJ) model  for opinion dynamics in an unweighted directed social network with $n$ nodes and $m$ edges. In the FJ model, the internal opinion of every node lies in the closed interval $[0, 1]$, with 0 and 1 being polar opposites of opinions about a certain issue. Concretely, we focus on the problem of selecting a small number of $ k\ll n $ nodes and changing their internal opinions to 0, in order to minimize the average opinion at equilibrium. We then design an algorithm that returns the optimal solution to the problem in $O(n^3)$ time. To speed up the computation, we further develop a fast algorithm by sampling  spanning forests, the time complexity of which is $ O(ln) $, with $l$ being the number of samplings. Finally, we execute extensive experiments on various real directed networks, which show that the effectiveness of our two algorithms is similar to each other, both of which  outperform several baseline strategies of node selection. Moreover, our fast algorithm is more efficient than the first one, which is scalable to massive graphs with more than twenty million nodes.

Opinion Optimization in Directed Social Networks

Modern social networks are dynamic in their nature; new connections are appearing, and old connections are disappearing all the time. However, in our algorithmic and complexity studies, we usually model social networks as static graphs.

In this paper, we propose a new paradigm for the study of the well-known Target Set Selection problem, which is a fundamental problem in viral marketing and the spread of opinion through social networks. In particular, we use temporal graphs to capture the dynamic nature of social networks.

We show that the temporal interpretation is, unsurprisingly, NP-complete in general. Then, we study the computational complexity of this problem for multiple restrictions of both the threshold function and the underlying graph structure and provide multiple hardness lower bounds.

Maximizing Influence Spread through a Dynamic Social Network

The tremendous increase in social media usage for sharing Television (TV) experiences has provided a unique opportunity in the Public Health and Marketing sectors to understand viewer engagement and attitudes through viewer-generated content on social media. However, this opportunity also comes with associated technical challenges. Specifically, given a televised event and related tweets about
this event, we need methods to effectively align these tweets and the corresponding event. 
In this paper, we consider the specific ecosystem of the Superbowl 2020 and map viewer tweets to advertisements they are referring to. Our proposed model, AdBERT, is an effective few-shot learning framework that can
handle the technical challenges of establishing ad-relatedness, class imbalance as well as the scarcity of labeled data. As part of this study, we have curated and developed two datasets that can prove useful for Social TV research: 1) dataset of ad-related tweets and 2) dataset of ad descriptions of Superbowl advertisements. Explaining connections to SentenceBERT, we describe the advantages of AdBERT that allow us to make the most out of a challenging and interesting dataset that we will open-source.

AdBERT: An Effective Few Shot Learning Framework for Aligning Tweets to Superbowl Advertisements

Code-mixing (CM) is a frequently observed phenomenon on social media platforms in multilingual societies such as India. While the increase in code-mixed content on these platforms provides good amount of data for studying various aspects of code-mixing, the lack of automated text analysis tools makes such studies difficult. To overcome the same, tools such as language identifiers and parts of-speech (POS) taggers for analysing code-mixed data have been developed. One such tool is Named Entity Recognition (NER), an important Natural Language Processing (NLP) task, which is not only a subtask of Information Extraction, but is also needed for downstream NLP tasks such as semantic role labeling. While entity extraction from social media data is generally difficult due to its informal nature, code-mixed data further complicates the problem due to its informal, unstructured and incomplete information. 
In this work, we present the first ever corpus for Kannada-English code-mixed social media data with the corresponding named entity tags for NER. We provide strong baselines with machine learning classification models such as CRF, Bi-LSTM, and Bi-LSTM-CRF on our corpus with word, character, and lexical features.


"Kanglish alli names!" Named Entity Recognition for Kannada-English Code-Mixed Social Media Data

Researchers across disciplines use Twitter geolocation tools to filter data for desired locations. These tools have largely been trained and tested on English tweets, often originating in the United States from almost a decade ago. Despite the importance of these tools for data curation, the impact of tweet language, country of origin, and creation date on tool performance remains largely unknown. We explore these issues with Carmen, a popular tool for Twitter geolocation. To support this study we introduce Carmen 2.0, a major update which includes the incorporation of GeoNames, a gazetteer that provides much broader coverage of locations. We evaluate using two new Twitter datasets, one for multilingual, multiyear geolocation evaluation, and another for usage trends over time. We found that language, country origin, and time does impact geolocation tool performance.

Changes in Tweet Geolocation over Time: A Study with Carmen 2.0

Gender analysis of Twitter can reveal important
socio-cultural differences between male and female
users. There has been a significant effort
to analyze and automatically infer gender in the
past for most widely spoken languages’ content,
however, to our knowledge very limited work
has been done for Arabic. In this paper, we
perform an extensive analysis of differences
between male and female users in the Arabic
Twitter-sphere. We study differences in user
engagement, topics of interest, and the gender
gap in professions. Along with gender analysis,
we also propose a method to infer gender
by utilizing usernames, profile pictures, tweets,
and networks of friends. In order to do so, we
manually annotated gender and locations for
∼167K Twitter accounts associated with ∼92K
user location, which we make publicly available.
1 Our proposed gender inference method
achieves an F1 score of 82.1% (47.3% higher
than the majority baseline). We also developed
a demo and made it publicly available.

https://alt.qcri.org/resources/ArabGend.zip
https://asad.qcri.org/

ArabGend: Gender Analysis and Inference on Arabic Twitter

Entity Linking (EL) is the gateway into Knowledge Bases. Recent advances in EL utilize dense retrieval approaches for Candidate Generation, which addresses some of the shortcomings of the Lookup based approach of matching NER mentions against pre-computed dictionaries. In this work, we show that in the domain of Tweets, such methods suffer as users often include informal spelling, limited context, and lack of specificity, among other issues. We investigate these challenges on a large and recent Tweets benchmark for EL, empirically evaluate lookup and dense retrieval approaches, and demonstrate a hybrid solution using long contextual representation from Wikipedia is necessary to achieve considerable gains over previous work, achieving 0.93 recall.

Robust Candidate Generation for Entity Linking on Short Social Media Texts

Monitoring vaccine behaviour through social media can guide health policy. We present a new dataset of 9471 tweets posted in Australia from 2020 to 2022, annotated with sentiment toward vaccines and also 5C, the five types
of behaviour toward vaccines, a scheme commonly used in health psychology literature. We benchmark our dataset using BERT and Gradient Boosting Machine and show that jointly training both sentiment and 5C tasks (F1=48) outperforms individual training (F1=39) in this highly imbalanced data. Our sentiment analysis
indicates close correlation between the sentiments and prominent events during the pandemic. We hope that our dataset and benchmark models will inform further work in online monitoring of vaccine behaviour. The dataset and benchmark methods are accessible online.

Automatic Identification of 5C Vaccine Behaviour on Social Media

The ability to track fine-grained emotions in customer service dialogues has many real-world applications, but has not been studied extensively. This paper measures the potential of prediction models on that task, based on a real-world dataset of Dutch Twitter conversations in the domain of customer service. We find that modeling emotion trajectories has a small, but measurable benefit compared to predictions based on isolated turns. The models used in our study are shown to generalize well to different companies and economic sectors.

An Emotional Journey: Detecting Emotion Trajectories in Dutch Customer Service Dialogues

Automatically detecting the intent of an utterance is important for various downstream natural language processing tasks. This task is also called Dialogue Act Classification (DAC) and was primarily researched on spoken one-to-one conversations. The rise of social media has made this an interesting data source to explore within DAC, although it comes with some difficulties: non-standard form, variety of language types (across and within platforms), and quickly evolving norms.
We therefore investigate the robustness of DAC on social media data in this paper. More concretely, we provide a benchmark that includes cross-domain data splits, as well as a variety of improvements on our %strong
transformer-based baseline. Our experiments show that lexical normalization is not beneficial in this setup, balancing the labels through resampling is beneficial in some cases, and incorporating context is crucial for this task and leads to the highest performance improvements (~7 F1 percentage points in-domain and ~20 cross-domain).

Increasing Robustness for Cross-domain Dialogue Act Classification on Social Media Data

This presentation covers participation of the SINAI team in the Task 10 of the Social Media Mining for Health (\#SSM4H) workshop at COLING-2022. This task focuses on leveraging Twitter posts written in Spanish for healthcare research. The objective to identify disease mentions in Twitter posts. The presented system explores large RoBERTa language model on general-domain data for the disease recognition task. We also present a text pre-processing methodology and describe an initial weakly-supervised fine-tuning phase alongside with a submission post-processing procedure. The system obtained 0.77 F1-score during the official evaluation.

Weakly Supervised fine-tuning for Disease Mention Detection in Spanish Tweets

This paper describes our system developed for the Social Media Mining for Health (SMM4H) 2022 SocialDisNER task. We used several types of pre-trained language models, which are trained on Spanish biomedical literature or Spanish Tweets. We showed the difference in performance depending on the quality of the tokenization as well as introducing silver standard annotations when training the model. Our model obtained a strict F1 of 80.3% on the test set, which is an improvement of +12.8% F1 (24.6 std) over the average results across all submissions to the SocialDisNER challenge.

Underline digital video library

Opinion Optimization in Directed Social Networks

Maximizing Influence Spread through a Dynamic Social Network

AdBERT: An Effective Few Shot Learning Framework for Aligning Tweets to Superbowl Advertisements

"Kanglish alli names!" Named Entity Recognition for Kannada-English Code-Mixed Social Media Data

Changes in Tweet Geolocation over Time: A Study with Carmen 2.0

ArabGend: Gender Analysis and Inference on Arabic Twitter

Robust Candidate Generation for Entity Linking on Short Social Media Texts

Automatic Identification of 5C Vaccine Behaviour on Social Media

An Emotional Journey: Detecting Emotion Trajectories in Dutch Customer Service Dialogues

Increasing Robustness for Cross-domain Dialogue Act Classification on Social Media Data

Weakly Supervised fine-tuning for Disease Mention Detection in Spanish Tweets

Extracting Disease Mentions in Tweets Written in Spanish

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