=Paper= {{Paper |id=Vol-3159/T7-1 |storemode=property |title=Overview of the Shared Task on Fake News Detection in Urdu at FIRE 2021 |pdfUrl=https://ceur-ws.org/Vol-3159/T7-1.pdf |volume=Vol-3159 |authors=Maaz Amjad,Sabur Butt,Hamza Imam Amjad,Alisa Zhila,Grigori Sidorov,Alexander Gelbukh |dblpUrl=https://dblp.org/rec/conf/fire/AmjadBAZSG21a }} ==Overview of the Shared Task on Fake News Detection in Urdu at FIRE 2021== https://ceur-ws.org/Vol-3159/T7-1.pdf
Overview of the Shared Task on Fake News
Detection in Urdu at FIRE 2021
Maaz Amjada , Sabur Butta , Hamza Imam Amjadc , Alisa Zhilab , Grigori Sidorova and
Alexander Gelbukha
a
  Instituto Politécnico Nacional (IPN), Center for Computing Research (CIC), Mexico
b
  Ronin Institute for Independent Scholarship, United States
c
  Moscow Institute of Physics and Technology, Russia


                                         Abstract
                                         Automatic detection of fake news is a highly important task in the contemporary world. This study
                                         reports the 2nd shared task called UrduFake@FIRE2021 on identifying fake news detection in Urdu
                                         language. The goal of the shared task is to motivate the community to come up with efficient methods for
                                         solving this vital problem, particularly for the Urdu language. The task is posed as a binary classification
                                         problem to label a given news article as a real or a fake news article. The organizers provide a dataset
                                         comprising news in five domains: (i) Health, (ii) Sports, (iii) Showbiz, (iv) Technology, and (v) Business,
                                         split into training and testing sets. The training set contains 1300 annotated news articles —750 real news,
                                         550 fake news, while the testing set contains 300 news articles —200 real, 100 fake news. 34 teams from 7
                                         different countries (China, Egypt, Israel, India, Mexico, Pakistan, and UAE) registered for participation in
                                         the UrduFake@FIRE2021 shared task. Out of those, 18 teams submitted their experimental results and
                                         11 of those submitted their technical reports, which is substantially higher compared to the UrduFake
                                         shared task in 2020 when only 6 teams submitted their technical reports. The technical reports submitted
                                         by the participants demonstrated different data representation techniques ranging from count-based
                                         BoW features to word vector embeddings as well as the use of numerous machine learning algorithms
                                         ranging from traditional SVM to various neural network architectures including Transformers such as
                                         BERT and RoBERTa. In this year’s competition, the best performing system obtained an F1-macro score
                                         of 0.679, which is lower than the past year’s best result of 0.907 F1-macro. Admittedly, while training
                                         sets from the past and the current years overlap to a large extent, the testing set provided this year is
                                         completely different.

                                         Keywords
                                         Natural Language Processing, NLP, fake news detection, shared task, Urdu language, text classification,
                                         low resource language, medium resource language




1. Introduction
The proliferation of social media brought in various forms of cybercrime that urgently need
automatic solution for the safety of people online and beyond [1, 2, 3]. Among these problems,
fake news dissemination is a critical problem that spreads in the form of advertisements, posts,

FIRE 21: Forum for Information Retrieval Evaluation, December 13–17, 2021, India
Envelope-Open maazamjad@phystech.edu (M. Amjad); sabur@nlp.cic.ipn.mx (S. Butt); hamzaimamamjad@phystech.edu
(H. I. Amjad); alisa.zhila@ronininstitute.org (A. Zhila); sidorov@cic.ipn.mx (G. Sidorov); gelbukh@gelbukh.com
(A. Gelbukh)
GLOBE https://nlp.cic.ipn.mx/maazamjad/ (M. Amjad)
                                       © 2021 Copyright for this paper by its authors. Use permitted under Creative Commons License Attribution 4.0 International (CC BY 4.0).
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news articles and others. It is an outstanding threat to journalism, democracy, and freedom
of expression that negatively affects trust between the media outlets and the users. The socio-
political impact of fake news can be observed with the incidents such as 2016 United States
presidential elections. Post election studies showed [4, 5] various occasions of fake news spiking
on social media with content emphasising nonexistent cause–effect relationship aggravating the
division between the political groups. Behavioural studies [6, 7] showed the effect that exposure
to fake news has on political and social issues through randomized controlled experiments.
The results established that fake news can cause a change in views and behaviour regarding
topics of broad domain including politics. Hence, the status quo of fake news needs immediate
attention and robust solutions.
   Natural language processing (NLP) researchers formulated the problem into subcategories of
fake news such as satire [8, 9], propaganda [10, 11], deception [12, 13], fact cherry picking [14, 15],
clickbaits [16, 17, 18], hyperpartisanship [19, 20], and claim “check-worthiness” for potentially
untruthful facts [21, 22, 23, 24, 25, 26]. Each subcategory has distinct features and solutions to
achieve desirable results. Fake news becomes a very challenging problem to control because
of the Velocity, Volume, Variety, and Time Latency of its spread [27]. The community behind
the fake news content marches the spread at a pace which becomes higher than the real news
dissemination itself.
   This paper describes the UrduFake@FIRE2021 shared task and its results. The task invited
the participants to tackle the problem of automatic fake news detection in Urdu in Nastalíq
script . The problem is shaped into a binary classification problem in which news articles from
various sources including such news outlets as BBC Urdu News, CNN Urdu, Express-News,
Jung News, Naway Waqat, and others, are offered for classification as fake or real. During the
active competition phase the ground truth annotations for the testing set were hidden from
the participants, while the training set was provided with the corresponding ground truth
annotations. After the end of the competition, the both parts of the dataset were made publicly
available along with the corresponding ground truth annotations at the CICLing 2021 UrduFake
track at FIRE 2021 shared task homesite 1 . This year’s track is the continuation of CICLing 2020
UrduFake track at FIRE 2020 [28, 29] with the core difference being the size of the offered dataset.
The training data has increased to facilitate a wider range of neural network and particularly
deep learning studies and to get more insightful information from data analysis. In the shared
task the participating teams were requested to submit only their top 3 different runs, among
which the best run was considered for submission of the technical report paper describing the
approach.
   The paper is structured as follows. An overview of previous relevant research can be found
in Section 3. We provide the task description in Section 4 and explain in detail the data
collection and annotation procedure in Section 5. Training and testing set splits and statistics are
outlined in Section 5.2. Sections 6 and 7 describe the choice of evaluation metrics and baselines
correspondingly. A high level overview and comparison of the solutions and approaches
submitted by the participants is provided in Section 8 along with the final results summarized
in Section Sections 9. A brief summary of the UrduFake@FIRE2021 track can be found in a
separate publication [30].

    1
        https://www.urdufake2021.cicling.org/home
2. Importance of Fake News Detection in Urdu
Urdu is the national language of Pakistan and has more than 230 million 2 speakers worldwide.
Many of these speakers carry out their written communication in the Nastalíq script. Urdu is
commonly written in the Nastalíq script, while the Devanagari script is commonly used for
Hindi. However, due to cultural and geographical proximity, Devanagari may be also used for
writing in Urdu. This creates a situation of digraphia for the Urdu language when two scripts
are used for writing in a language. Apart from this commonality, Urdu has other structural
similarities with Hindi and other South Asian languages [31]. The emergence of Urdu came
in the form of tribal movement which resulted in the merging of morphological and syntactic
structures of Arabic, Persian, Turkish, Sanskrit, and recently English in the conversational usage.
Due to the mixture of various languages, Urdu has more complexity than the other existing
languages and, consequently, requires more careful processing.
   South Asia has been suffering from numerous instances of fake news affecting its political,
social, and economic situation. For example, Dr. Shahid Masood 3 who works as a TV anchor
in Pakistan, was exiled and tortured for spreading false information about a child rape case.
Another case of fake news in India was reported in the Washington Post 4 , where many innocent
people died because of a child trafficking report.
   These severe consequences of fake news reporting surge the urge for high quality automa-
tion of fake news detection in Urdu. Given that despite the numerous speakers Urdu is still a
low/medium resourced language, we strive for providing larger annotated datasets and incen-
tivize the community to develop state-of-the-art solutions for early detection of fake news.


3. Literature Review
Contemporary fake news is not solely produced by humans, but can also be generated through
bots [32]. These bots replicate human behaviour and are created for the purpose of spamming,
spreading rumours and misinformation on various social media platforms. Social context [27]
has been one of the key indicators to differentiate between fake and real news patterns. Re-
searcher have dealt with the fake news problem with the aid of a wide range of feature based
approaches [33, 34, 35, 36, 37] including features such as engagement, user attributes, stylistic
features, linguistic features, and personality based features.
   Earlier solutions [27] in fake news detection used fact checking with the aid of experts,
however, the solution was time consuming and labor-cost intensive. Hence, NLP experts moved
on to finding automatic solutions based on machine learning and deep learning algorithms [38,
39, 40, 41]. Studies have found unique emotional language cues [42] and emotional pattern [43]
differences between real and fake news. Among the supervised machine learning techniques [38,
44, 45], we have seen Random Forest (RF), Support Vector Machine (SVM), and Decision Trees
repeatedly used for fake news detection. Other research have used neural network ensembles
combining various neural network architectures. Thus, Roy et al. [41] fed article representations

   2
     https://www.statista.com/statistics/266808/the-most-spoken-languages-worldwide/
   3
     https://www.globalvillagespace.com/dr-shahid-masoods-claims-about-zainabs-murderer-prove-false/
   4
     https://tinyurl.com/ynhsudnx
provided by CNN and Bi-LSTM models into MLP for the final classification which allowed for
considering more contextual information. Yet another approach towards identifying fake news
is looking at the news sources instead of the text content in the article, as news sources can
provide valuable insights [46].
   The dataset created for fake news identification mostly rely on social media platforms and
news outlets. The majority of the existing datasets are available in English [29, 27]. Recently,
datasets and studies on various subcategories of fake news appeared in other languages: Persian
[47], Spanish [46, 48], Arabic [49, 50], German [51], Bangla [11], Dutch [19], Italian [52],
Portuguese [53], Urdu [54], and Hindi [55].
   Some of the online challenges to improve automatic fake news systems include Fake News
Challenge 5 , multiple fake news detection competitions on Kaggle 6 as well as shared task tracks
organized by the academic community: PAN 2020 [46], RumourEval Task 8 of SemEval 2017 for
English [56], RumourEval Task 7 of SemEval-2019 for English [57], and others.


4. Task Description
This task is aimed to motivate the community to come up with methods and systems for
automatic fake news detection in Urdu language by providing an annotated dataset with a
train/test split and competitive settings. The challenge is posed as a binary classification task
where participants are to train their classifiers on the provided training part of the dataset and
to submit the labels, either fake or real, for each news article from the testing set, the ground
truth annotations for the latter being hidden from the participants. Organizers compute the
evaluation metrics for each submission by comparing the submitted labels to the ground truth
annotations.
   The motivations of this shared task is to investigate whether and to which extent the textual
content alone can be grounds for fake news detection and examine the efficiency of machine
learning algorithms in identifying fake news articles written in Urdu in the Nastalíq script.
   Here, a fake news article and fake news detection are defined as follows:

    • F a k e N e w s : A news article that contains factually incorrect information with the intention
      to deceive a reader and to make the reader believe that it is factually correct.
    • F a k e N e w s D e t e c t i o n : Suppose that 𝑛 is a news article (without annotation) and 𝑛 ∈ 𝑁,
      where 𝑁 is the total number of news articles. A fake news detection is a process in which
      an algorithm calculates the likelihood of whether a given news article 𝑛 is a fake news
      article by assigning a value between 0 and 1. In mathematical terms, this can be described
      as 𝑆(𝑛) ∈ [0, 1]. In other words, if 𝑆(𝑛)̂ > 𝑆(𝑛), this indicates that the 𝑛̂ new article has a
      higher chances to be fake news than the 𝑛 news article. Also, it is important to define
      a threshold. The threshold 𝛽 is a hyperparameter cut value selected by the algorithm
      developers such that if the algorithm assigns an equal or higher value to a news article as
      compared to the threshold, then the news article will be tagged as fake. A threshold 𝛽
      can be defined so that the prediction function 𝐹 (𝑛): 𝑛 → {not fake, fake} is:

   5
       http://www.fakenewschallenge.org/
   6
       https://www.kaggle.com/c/fake-news/data, https://www.kaggle.com/c/fakenewskdd2020
                                                   𝑓 𝑎𝑘𝑒, 𝑖𝑓 𝑆(𝑛) >= 𝛽),
                                      𝐹 (𝑁 ) = {
                                                   𝑛𝑜𝑡𝑓 𝑎𝑘𝑒, otherwise.

  More elaborated definition of fake news is provided in our previous work [54].


5. Dataset Collection and Annotation
This section gives an outline of the dataset created for the UrduFake shared task at FIRE 2021.
Our previous research [54] reported the first version of this dataset, called “Bend The Truth”
that contained 500 real news and 400 corresponding fake news. A new training dataset and test
dataset data was acquired using the dataset collection and annotation guidelines presented in
our previous research [54]. The dataset presented in this shared task is publicly available and
can be used for research objectives 7 .
    The training dataset was released on April 30, 2021 8 . It is important to mention that the
training dataset used in 2021 UrduFake task comprised 1300 news article. This dataset was
made up by combining the training dataset, which we presented in our previous research [54]
“Bend The Truth” and testing dataset collected for UrduFake 2020 shared task. The training
dataset contained 750 real news articles and 550 fake news articles. we presented a new test
dataset that contained 200 real news and 100 fake news articles collected from January 2021 to
August 2021 to test the proposed systems.
    A crowdsourcing technique was used to collect the fake news articles. In other words, the
fake news were composed by hiring professional journalists who deliberately wrote fake news
of the corresponding real news. The journalists were provided a set of instructions to follow
while writing fake news articles. This dataset contains five domains of the news: (i) Business,
(ii) Health, (iii) Sports, (iv) Showbiz (entertainment), and (v) Technology.

5.1. Procedure for Dataset Annotation
All the news articles were labelled into two two types of news: (i) real news article, and (ii) fake
news article. Different techniques were used to annotate and assemble real and fake news. This
dataset can be used for future research using supervised machine learning and deep learning
techniques. Figure 1 shows the list of news organizations used to crawl news articles.

5.1.1. Real News Collection and Annotation
To assemble real news articles, various traditional news media mainstream were used to crawl
news manually. Manual procedures were followed to annotate a news article using the underline
guidelines, the news would label as real news. The news organizations used to gather news
items for annotation are presented in Figure 1 and all the news were manually crawled. The
following guidelines were used to annotate a news item as a real news:
    7
        https://github.com/MaazAmjad/Urdu-Fake-news-detection-FIRE2021
    8
        https://www.urdufake2021.cicling.org/home
Figure 1: Legitimate websites


   1. The news article was labeled as real news if the news meets the following criteria:
         • That news article is published by a credible newspaper or a prominent news media
           agency.
         • The integrity of that news article can be verified by other credible newspaper
           agencies. This was an important point to do fact-checking. For example, manual
           source verification was performed to check place of the event, image, date of the
           news and whether the provided information in the news article matched with the
           same news article but published by other newspaper or news agency as well.
         • Incongruity between news titles and its content was also confirmed to ensure that a
           news article has a correlation between the news headline and the body text. We
           read the complete news articles to check the incongruity between news titles and
           the body text.

   It is important to highlight that a news article was removed If it did not fulfil one of the
aforementioned criteria. Different news articles contained different words length. For example,
CNN publish news articles that contains between 200-300 words. On the other hand, a news
article published by BBC Urdu news typically contains on average 1500 words. Therefore, the
real news articles contains heterogeneous length of words. This is how all the real news articles
were collected and annotated.

5.1.2. Professional Crowdsourcing of Fake News
To obtain fake news, the services of professional journalist were used who work in different
news organizations in Pakistan. We hired professional columnist because they are expertise in
writing news articles, and use different journalists techniques to make the news interesting to
hook and and their written fake news can easily trick the reader. The real news articles were
provided to the journalists and they were asked to write fake news corresponding to the real
news. In other words, if a real news contains story about football, the correspond fake news
article should also contain similar story but with fabricated information.
   We used professional “crowdsourcing” for collecting fake news and the reasons are described
as follows:

   1. The news articles analysis with manual procedures for verification through web scraping
      approach was unfeasible. This is due to the facet that it is extremely challenging task to
      find the corresponding fake news of a real news article.
   2. No online service in Urdu language is available for news fact-checking. Unlike English,
      the news fact-checking is manually performed in Urdu.

   This dataset contains news of five domains: (i) business, (ii) education, (iii) sports, (iv)
showbiz (entertainment), and (v) technology. The journalists expertise was taken into account
to ensure that the fake news corresponding to the real news is written by the domain expert.
The journalists were asked to keep the same length of the news (fake news article should have
the same words length as real news). In addition, we also instructed journalists to mitigate
defined patterns so that the undesirable clues should not be induced to classify news articles.
Therefore, journalists’ expertise were used to collected all the fake news articles.

5.2. Training and Testing Split
5.2.1. Training and Validation Set
The training set contained 1300 news articles, in which 750 news articles were annotated as
real, and 550 news articles were annotated as fake news article. The training set and the testing
set contained five types of news: (i) Business, (ii) Health, (iii) Showbiz (entertainment), (iv)
Sports, and (v) Technology. Participants were allowed to use of the training set for validation,
development, and parameter tuning. The training dataset made up by combining the training
dataset, which we presented in our previous research [54] “Bend The Truth” and the testing
dataset collected for UrduFake 2020 shared task.

5.2.2. Test dataset
The new test set was introduced that contained 200 real news and 100 fake news articles collected
from January 2021 to August 2021. The test set was presented without the ground truth labels
so that all the participants could evaluate and test the performance of their proposed systems.
To evaluate and compare the performance of the classifiers submitted by the participants, the
organizers used the truth labels of the test set. It is worth mentioning that the participants were
unaware of the distributions of real and fake news in the test set.

5.3. Dataset Statistics
In this shared task, we divided the dataset into two parts: (i) training set, and (ii) testing set.
Initially, the training set was released so that the participants can train their classification
models. Then, the test set was released so that the participants can predict the labels of whether
a given news is real or fake. Table 1 describes the corpus distribution of the news articles by
topics for the training and testing sets.

Table 1
Domain Distribution in Train and Test subsets
                                                   Train          Test
                                 Domain
                                                real fake      real fake
                                 Business        150     80     40       20
                                 Health          150    130     40       20
                                 Showbiz         150    130     40       20
                                 Sports          150     80     40       20
                                 Technology      150    130     40       20
                                 Totals          750    550     200      100




6. Evaluation Metrics
This is a binary classification task in which the task is to classify a news article as fake or real.
All the participating teams were allowed to submit up to 3 different runs, i.e., labels for the
testing set generated by their proposed classifiers. The ground truth annotations were used to
compare the labels predicted by the participants’ classifiers. We used the evaluation metrics
commonly used to measure the performance of binary classification on imbalanced datasets:
two sets of Precision (P), Recall (R), and F1 score, one for the “real” class treated as a target
class and the other for the “fake” class; the inter-class metrics Accuracy and F1-macro. The
macro-averaged F1-macro, which is the average of F1real and F1fake , was also calculated to
accommodate the dataset skew towards the real class. As detection of both classes (real and
fake) is equally important, this is why we evaluated performance against both classes.


7. Baselines
To introduce a baseline, we used the bag of words (BoW) approach. We used a combination
of character, word, and function word bi-grams with TF-IDF weighting scheme for text repre-
sentation. Function words are similar to stopwords, for more elaborated definition and list we
suggest to refer to [58]. Decision Tree was selected as a classifier, which achieved surprisingly
good results compared to other traditional ML classifiers on our trial runs. d In the trial runs,
five weighting schemes (tf-idf, log-ent, norm, binary, relative frequency) [54] were used for
the experiments along with different machine learning classifiers such Decision Tree, Random
Forest, Logistic Regression, AdaBoost, SVM, and Naive Bayes. We tried different 𝑛-grams,
𝑛 = {1, ..., 7}. We noticed that the classifiers started to obtain insignificant results when 𝑛 = 5 or
higher. Finally, the Decision Tree algorithm outperformed other classifiers in identifying fake
news. The baseline code is publicaly available 9 .

    9
        https://github.com/MaazAmjad/Urdu-Fake-news-detection-FIRE2021
8. Overview of the Submitted Approaches
This section briefly overviews the methods applied in the competition by the teams. In total 34
teams registered for the competition, and 18 teams submitted experimental results on a test
dataset. We report the findings of 11 teams who submitted their methodologies in the form
of technical report papers. The registered participants were from the countries where Urdu
language has presence or cause interest: Pakistan, India, United Arab Emirates, Israel, and
Egypt. Table 2 shows the approaches used by the teams and table 3 tells the best run scores
achieved through those methods.

   1. Nayel: The best performing model used the linear classifier function from the scikit-learn
      package s k l e a r n . l i n e a r _ m o d e l . S G D C l a s s i f i e r that by default fits a linear SVM classifier
      with Stochastic Gradient Descent (SGD) optimization algorithm. The team trained it
      on word token tri-gram features weighted with TF-IDF scheme. The model uses tokens
      without any preprocessing, which increases the number of features.
   2. Abdullah-Khurem: The team experimented with neural network techniques: Convo-
      lutional Neural Network (CNN), Recurrent Neural Network (RNN) and textCNN, for fake
      news detection in Urdu. The final submission used textCNN with TF-IDF features which
      and ranked second in the competition.
   3. Hammad-Khurem: The methodology used no pro-processing and proposed a voting-
      based approach with a majority voting ensemble of boosting-based ML classifiers: Ad-
      aBoost, LightGBM and XGBoost. The proposed approach employed BoW features.
   4. Muhammad Homayoun: The participant reported results using Convolution Neural
      Network (CNN) with four input channels. Before classification, the data was pre-processed
      by removing diacritic, normalization, stopword removal and lemmatization. The best
      results submitted used character level sequences (n-grams) for text representation.
   5. Snehaan Bhawal: The transformer methods (MuRIL, BERT) gave the best results with
      no pro-processing. Multilingual Representations for Indian Languages (MuRIL) was
      submitted to the competition as the final submission and slightly outranked the non-
      specialized BERT.
   6. MUCIC: The participants used three feature selection algorithms (Chi-square, Mutual
      Information Gain (MIG), and f_classif) to choose the best features from the word and
      character n-grams. The intersection of selected features was passed into an ensemble of
      ML classifiers (Linear SVM (LSVM), LR, MLP, XGB, and RF) with soft voting and feature
      selection to achieve the best results.
   7. SOA NLP: The submitted method used character level uni, bi and tri-gram TF-IDF features
      as an input to dense neural network (DNN). The best results used a learning rate of 0.001,
      a dropout rate of 0.3, a batch size of 16, Adam as an optimizer and binary cross-entropy
      as a loss function with 100 epoch training.
   8. Dinamore&Elyasafdi_SVC: The team used classical machine learning algorithms: SVM,
      Random Forest (RF), and Logistic Regression (LR). They used character tri-gram features
      with only one pre-processing step of lowercasing all letters.
   9. MUCS: In the pre-processing stage the participants removed non-relevant characters,
      stopwords and punctuation. They used pre-trained Urdu word embeddings from fastText
      and TF-IDF of words as well as character n-grams as features. Similar to team MUCIC, an
      ensemble of ML classifiers (RF, MLP, AdaBoost, and GraidentBoost) were used with soft
      voting to achieve the highest F1 macro.
  10. Iqra Ameer: This is another study that used BERT-base model. The best results were
      reported using both the training and validation set for training of the model.
  11. Sakshi Kalra: The best team runs used an ensemble of various transformer methods
      (RoBERTa, XLM-RoBERTa and Multilingual BERT) as well as a single specialized trans-
      former RoBERTa-urdu-small. The text input was normalized. Interestingly, the best
      performing method on the test set turned out to be RoBERTa-urdu-small which exceeded
      the three-transformer ensemble method (XLM-RoBERTa+Multilingual BERT+RoBERta).


Table 2
Approaches used by the participating teams
  System/Team Name              Text Representation             Feature Weighting Scheme           Classifying Algorithm            is NN-based?
           Nayel                        tri-gram                         TF-IDF                       linear SVM with SGD                 No
    Abdullah-Khurem           Word2Vec, GloVe, fastText                  TF-IDF                              textCNN                      Yes
    Hammad-Khurem                         BoW                           count (?)            ensemble XGBoost+LightGBM+AdaBoost           No
  Muhammad Homayoun                  char 2, 6-gram                        N/A                                 CNN                        Yes
     Snehaan Bhawal            transformer embeddings                      N/A                                MuRIL                       Yes
          MUCIC                 word- & char 1, 2-grams                  TF-IDF                ensemble linSVM+LR+MLP+XGB+RF        Yes (MLP) & No
         SOA NLP                    char 1, 3-grams                      TF-IDF                                DNN                        Yes
 Dinamore&Elyasafdi_SVC               char 3-grams                       TF-IDF                                SVM                        No
          MUCS            word fastText emb & char 2, 3-grams     TF-IDF for char-grams    ensemble MLP+AdaBoost+GraidentBoost+RF   Yes (MLP) & No
        Iqra Ameer                 transformer emb                         N/A                              BERT-base                     Yes
       Sakshi Kalra                transformer emb                         N/A                         RoBERTa-urdu-small                 Yes




9. Results and Discussion
Each team submitted three runs (proposed three different systems), and only the best run was
considered for comparison. We calculated the results of all the submitted runs by each teams
individually and only reported the results obtained by the best run. Table 3 shows the the
results of the best run (among up to three submitted runs) submitted by the participating teams.
We used F1-macro score to rank the participants systems. The aggregated statistics about the
performance is presented in Table 4.
   It can be observed that only two systems outperformed the baseline, and all the other systems
did not beat the F1-macro score of the baseline. The team Nayel obtained the the best results in
terms of F1-macro, Accuracy, Pfake (precision) scores. The team Abdullah-Khurem obtained
the the second best results in terms of F1-macro, Accuracy, Rfake (recall), Preal (precision), and
F1fake scores. Moreover, the baseline approach with the combination of char-word-function
words bi-gram with tf-idf weighting scheme using Decision Tree classifier the third position in
the shared task with the difference of 2.8% from Nayel system and 1.2% from Abdullah-Khurem
system in F1-macro score.
   Table 3 presents the best results of the submitted systems.
   Table 4 presents aggregated statistics of the submitted systems.
Table 3
Participants’ best run scores.
                                           Fake Class                  Real Class
 No    Team Names
                                   Prec     Recall F1_Fake     Prec     Recall F1_Real   F1_Macro      Accuracy
 1     Nayel                       0.754    0.400   0.522      0.757    0.935   0.836    0.679         0.756
 2     Abdullah-Khurem             0.592    0.480   0.530      0.762    0.835   0.797    0.663         0.716
 3     Baseline                    0.584    0.450   0.508      0.753    0.840   0.794    0.651         0.710
 4     Hammad-Khurem               0.634    0.330   0.434      0.729    0.905   0.808    0.621         0.713
 5     Muhammad Homayoun           0.480    0.490   0.485      0.742    0.735   0.738    0.611         0.653
 6     Snehaan bhawal              0.960    0.240   0.384      0.723    0.995   0.837    0.610         0.743
 7     MUCIC                       0.821    0.230   0.359      0.716    0.975   0.826    0.592         0.726
 8     SOA NLP                     0.793    0.230   0.356      0.356    0.715   0.823    0.590         0.590
 9     Dinamore & Elyasafdi _SVC   0.720    0.180   0.288      0.701    0.965   0.812    0.550         0.703
 10    MUCS                        0.850    0.170   0.283      0.703    0.985   0.820    0.552         0.713
 11    Iqra Ameer                  0.454    0.100   0.163      0.676    0.940   0.786    0.475         0.660
 12    Sakshi kalra                0.266    0.120   0.165      0.654    0.835   0.734    0.449         0.596


Table 4
Aggregated statistics of the submitted systems and the baseline.
          Stat. metric     Pfake    Rfake     F1fake   Preal    Rreal     F1real   F1-macro    Acc.
                 mean      0.596    0.294     0.348    0.679    0.837     0.757        0.553   0.658
                    std    0.201    0.171     0.136    0.105    0.201     0.137        0.093   0.106
                  min      0.262    0.070     0.115    0.356    0.155     0.228        0.296   0.303
         percentil 10%     0.319    0.100     0.165    0.610    0.684     0.713        0.448   0.584
         percentil 25%     0.462    0.145     0.229    0.680    0.802     0.761        0.490   0.646
         percentil 50%     0.592    0.240     0.364    0.716    0.905     0.797        0.590   0.686
         percentil 75%     0.737    0.430     0.451    0.726    0.970     0.816         0.61   0.713
         percentil 80%     0.769    0.462     0.473    0.734    0.975     0.821        0.615   0.714
         percentil 90%     0.826    0.506     0.510    0.753    0.981     0.828        0.653   0.729
                  max      0.960    0.600     0.530    0.762    0.995     0.837        0.679   0.756


10. Conclusion
Automatic fake news detection is an important task, especially in low resource languages. This
research presents the second shared task (the first task was organized in 2020) in identifying
fake news in Urdu namely the UrduFake 2021 track at FIRE 2021. A training and testing dataset
was presented so that the participants could train and test their proposed systems. The dataset
contained news in five domains (business, health, sports, showbiz, and technology). All the real
news were crawled from credible sources and manually annotated while the fake news were
written by the professional journalists.
  In this shared task, thirty four teams from seven different countries registered and eighteen
teams submitted their proposed systems (runs). The participants used different techniques
ranging from the traditional feature-crafting and application of traditional ML algorithms to
word representation through pre-trained embeddings to contextual representation and end-to-
end neural network based methods. The approaches used included ensemble methods, CNN,
and non-Urdu specialized Transformers (BERT, RoBERTa) as well as Urdu-specialized (MuRIL,
RoBERTa-urdu-small) .
   Team Nayel outperformed all the proposed systems by using the linear SVM optimized with
Stochastic Gradient Descent and obtained F1-macro score of 0.67. This result reveals that
classical feature-based models perform better compared to the contextual representation and
large neural network algorithms. The characteristics of the dataset require further investigation
to better explain this observation.
   This shared task aims to attract and encourage researchers working in different NLP domains
to address the automatic fake news detection task and help to mitigate the proliferation of fake
content on the web. Moreover, this also offers a unique opportunity to explore the sufficiency of
textual content modality alone and effectiveness of fusion methods. In addition, an annotated
news dataset in Urdu is also provided to encourage more research to address the automatic fake
news detection in Urdu language.


Acknowledgments
This competition was organized with the support from the Mexican Government through the
grant A1-S- 47854 of the CONACYT, Mexico and grants 20211784, 20211884, and 20211178 of
the Secretaría de Investigación y Posgrado of the Instituto Politécnico Nacional, Mexico.


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