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Learning from Social Media and Contextualisation

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Open Archive Toulouse Archive Ouverte

OATAO is an open access repository that collects the work of Toulouse researchers and makes it freely available over the web where possible

This is an author’s version published in: http://oatao.univ-toulouse.fr/22354

Any correspondence concerning this service should be sent to the repository administrator:

tech-oatao@listes-diff.inp-toulouse.fr

To cite this version:

Mothe, Josiane Learning from Social Media and Contextualisation. (2018) In: Dagstuhl Seminar 17301 (2017), 24 July 2017 - 28 July 2017 (Dagstuhl, Germany).

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L

EARNING FROM

S

OCIAL

M

EDIA

&

C

ONTEXTUALISATION

Josiane.Mothe@irit.fr

User-Generated Content in Social Media Dagstuhl Seminar July 2017

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R

ESEARCH

O

BJECTIVES

Learning from Social Media: main trends vs peculiarities

Information Mining to extract main trends and behaviour

Main topics

Main users (e.g. influential users on a topic) Following dissemination (e.g. flu, typhon)

Link between information (e.g. location information extraction)

Information Mining to detect peculiarities and weak signals

Used in Business Intelligence

Knowledge of the environment / contexts Detect opportunities / risks

Detect changes

2

(4)

R

ELATED

W

ORK IN

D

EPRESSION

D

ETECTION

Supervised learning based on 6 main groups of features:

N-grams: unigram, bigram and trigram [Yang et al., 2015];

Relevant Lexicons: depression symptoms, lexicon of drug names etc.(wikipedia);

Linguistic Style: frequency of negative word, quantifiers, quantity of first personal pronoun, quantity of emoticons,

numbers of exclamation and question marks etc. [Coppersmith

et al., 2014];

Users Behaviors: number of words/posts, proportion of reply posts from a user per day etc., user’s active period or posting time span [Choudhury, 2016];

Sentiment analysis: sentence polarity, sentiment words -positive and negative sentiment [Mowery et al., 2016];

Emotion analysis: categories of emotions - emotional degree [Choudhury, 2016].

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O

UR

N

ATURAL

L

ANGUAGE

P

ROCESSING

A

PPROACH 4 Users’ writing (posts and comments) Features Extraction Test Train Machine Learning Application Feature Selection Evaluation Model Preprocess

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5 M

AIN

G

ROUPS OF

E

XTRACTED

F

EATURES

Bag of Words: 18 most frequent unigrams (depressive)

-our baseline

Group 1: Language Style 13 features

Negation frequency

Group 2: Self-Preoccupation 9 features

Frequency of Personal Pronouns

Group 3: Reminiscence and Relevant Words 5+5 f

Past tense

Reference to related drugs

Group 4: Sentiment and Emotion 3+8 features

Positive sentiment

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E

XPERIMENTAL

F

RAMEWORK

:

E

R

ISK

D

ATA AND

W

EKA

6

CLEF eRisk 2017: early risk prediction of

depression from data extracted from Reddit (american social news aggregation, web content

rating, and discussion website.)

6

D. Losada, F. Crestani. A Test Collection for Research on Depression

and Language Use. Conference and Labs of the Evalutation Forum

(CLEF), 2016

Training: 403 Non-depressive + 83 Depressive Testing: 349 Non-depressive + 52 Depressive

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R

ESULTS

Model 1: Baseline + Group 1: Language Style;

Model 2: Features of Model 1 + Group 2: Self-Preoccupation; Model 3: Features of Model 2 + Group 3: Reminiscence and Relevant Words;

Model 4: Features of Model 3 + Group 4: Sentiment and Emotion. 7

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ML

FOR

D

ETECTING

L

OCATION

8

Jamie Fox tonight in Budapest

waiting for someone to jump off the 4th floor of

a building.

If you love NY,

watch this video and take action

against

CONTAIN a LOCATION

Predicting

and

recognizing

location names in tweets

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ML

FOR

D

ETECTING

L

OCATION 9 Data Set Data Analysis Features Extraction Algorithms Location Prediction Predictive model

- Twitter posts - Observability

- RF

- SVM

- NB

- …

- Binary classifier - Contain a word appearing

in geography gazetteer. - Contain preposition right

before proper nouns. - ….

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ML

FOR

D

ETECTING

L

OCATION

Features Collections

Existing (Ritter’s; MSM2013) New (1% tweet)

ML: Naïve Bayes, SVM, Random Forest Results

Accuracy: from 84 % to 94% (prediction of occurrence)

Increases accuracy of location extraction

Current: predict diffusion

10

Thi Bich Ngoc Hoang, Josiane Mothe,

Location Extraction from Tweets

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R

ESEARCH

T

OPICS

Learning from Social Media

Contextualization

Developed a CLEF task 2011-> now

Aim: provide context to help short text understanding

Collection: 1,000 tweets + Wikipedia Mean: multi-document summarization

Evaluation: informativeness & readability Outcome and main results

11

Patrice Bellot et al.

INEX Tweet Contextualization task: Evaluation, results and lesson learned.

(13)

C

ONTEXTUALIZATION 12 Method Document retrieval Sentence retrieval Sentence ordering

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C

ONTEXTUALIZATION

Contribution

Sentence weighting using many parameters

Content Syntax

Dependences

Graph theory to order sentences Topic/comment model

13

Liana Ermakova.

A Method for Short Message Contextualization: Experiments at CLEF/INEX.

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R

ESEARCH

R

ESULTS

Trust in information

How trust in Wikipedia evolves: a survey of students aged 11 to 25 Josiane Mothe, Gilles Sahut

Event dissemination

News Dissemination on Twitter and Conventional News Channels

A Seth, S Nayak, J Mothe, S Jadhay

Detecting changes in behaviour

Early detection of depression (CLEF e-risk 2017)

F. Benamara, Z. He, J. Mothe, V. Moriceau, F. Ramiandriosa,

Detection of locations in short messages

Location extraction from tweeter

T. B. N. Hoang, J. Mothe IPM 2017 (submitted)

Short text (tweet) contextualization

Task and collections (CLEF 2011 – 17) P. Bellot et al.

INEX Tweet Contextualization task: Evaluation, results and lesson learned. IPM 52(5):801-819, 2016

Propositions

Liana Ermakova (PhD), CLEF 2015

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