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Forecasting Country Stability in North Africa
V.S. Subrahmanian (UMD + Sentimetrix)[email protected]
Joint work withSteven Banaszak (Sentimetrix)
Liz Bowman (US Army)John Dickerson (CMU + Sentimetrix)
Sentimetrix - JISIC, The Hague, Sep 2014 1
Research Goal
Can we accurately predict various stability related events in North Africa (Egypt, Morocco, Sudan) by mining sentiment in open source data on various key players, even with a relative paucity of longitudinal data (36 time points)?
Sentimetrix - JISIC, The Hague, Sep 2014 2
Research Goal
• Provide a single dashboard that will enable an analyst to– See international stability situation at a glance
– Focus on countries of interest to him
– Look at forecasts in countries of interest to him
– Understand the rationale for the forecasts
– Understand the “why” around those forecasts
– Understand relationship between sentiment on different entities and stability events in countries
• This study focuses on Egypt, Morocco, and Sudan.
Sentimetrix - JISIC, The Hague, Sep 2014 3
Dependent Variables
• The current SentiBility (SB) system has 5 DVs:– Battles (did government engage in battles?)
– WonBattles (did gov win territory)
– LostBattles (did gov lose battles)
– Riots/Protests (were there riots and/or protests?)
– Violence Against Civilians
• These are the phenomena we are trying to predict.
• Historical data on DVs collected using ACCLED data set from University of Sussex for 36 months.
Sentimetrix - JISIC, The Hague, Sep 2014 5
Independent Variables: Data
• Political Entity Dataset (PED): set of key political leaders, parties, opposition groups, for each country.
• Hybrid Article Dataset (HAD): For each entity in PED, identified a set of articles (blog posts, news, tweets, forums) that reference that entity.
• Open-Source Sentiment DB: Assigns a score in [-1,+1] to each article-entity pair, specifying sentiment score of entity in the article.– -1 denotes maximally negative score– +1 shows maximally positive score– 0 is completely neutral
• Data about IVs was collected for 2-3 years varying by country during the 2008-2011 time frame.
Sentimetrix - JISIC, The Hague, Sep 2014 6
Sentiment Scoring
Used Sentimetrix’s Sentiment Scoring Engine which leverages many past papers by us:
• V.S. Subrahmanian et al. US Patent US 8296168 B2 System and method for analysis of an opinion expressed in documents with regard to a particular topic, Priority date Sep 13 2006
• Subrahmanian, V. S., and Diego Reforgiato. "AVA: Adjective-verb-adverb combinations for sentiment analysis." IEEE Intelligent Systems, 23.4 (2008): 43-50.
• Cesarano, Carmine, et al. "Opinion Analysis in Document Databases." AAAI Spring Symposium: Computational Approaches to Analyzing Weblogs. 2006.
Sentimetrix - JISIC, The Hague, Sep 2014 7
Learning Classifiers
• Training/validation set was an approximately 70/30 split.• Applied an ensemble of 5 classifier families
– Gaussian NB – Support Vector Machines– Random forests– AdaBoost– GradientBoost
• Each classifier family was optimized using leave-one-out cross validation via a hyper-parameter grid search to find best parameters.
• Different classifier families were best for different predictions (country-event).
Sentimetrix - JISIC, The Hague, Sep 2014 8
Egypt Case Study
• High sentiment on Adel Labib inversely correlated with violence against civilians.
• High sentiment on Ahmed Ghanem inversely correlated with riots/protests.
• When sentiment on Morso, El-Baradei, and Tantawi were all high, then there were few battles.
Sentimetrix - JISIC, The Hague, Sep 2014 10
Egypt Case Study: Multivariate Forecast Accuracy
Dependent Variable Forecast Accuracy
Battle 72%
Violence against Civilians 90%
Riots and Protests 90%
Sentimetrix - JISIC, The Hague, Sep 2014 11
Sudan Case Study: Multivariate Forecast Accuracy
Dependent Variable Forecast Accuracy
Won-Battle 69%
Riots and Protests 88%
Sentimetrix - JISIC, The Hague, Sep 2014 13
Contact Information
V.S. Subrahmanian
Founder
Sentimetrix, Inc.
@vssubrah
www.sentimetrix.com
Sentimetrix - JISIC, The Hague, Sep 2014 17