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Poorva Potdar Sentiment and Textual analysis of Create-Debate data EECS 595 – End Term Project

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Poorva Potdar Sentiment and Textual analysis of Create-Debate data EECS 595 End Term Project Slide 2 EUREKA!! Getting the Idea Why sentiment analysis? Huge amount of opinionated Text on web Sentiment Analysis on web popularity of a product, movie or a person as such. Idea: Create Debate online debating forum where people argue for/against some topic. Mine for the salient text features for agreement/disagreement posts. Slide 3 Math -14308 Debates. -983800 Sentences! -178290 Posts, -9194 Users - Labeled dataset Neutral Agreement Disagreement Structural Analysis Certain features of the language in the post that make it a high score agreement/disagreement post. Behavioral Analysis Aspects of Users behavior that give him a high rank on the forum. Creating the Haystack . Slide 4 What's the gain? Influence detection in a community Sub-Group Detection Stance Identification Are there any visible groups with a particular stance? Predict the Crowd Trend for a particular topic of interest? Text Summarization Slide 5 Correlation between polarity of the post Vs its score? Popular pattern observed in the dependency parse of agreement/disagreement posts? Emoticons? Are posts with formal text up-voted often? Finding the needle - structural features . Slide 6 Experiment 1 : Polarity Measure Intuition : Is the number of +ve/-ve words an indicative of how popular a post is? Tool Opinion Finder/ Wordnet. Output of processed data by Opinion Finder. It think it's wrong to assume that in order to be a revolutionary thinker you have to be crazy MPQAPOL Indicates the polarity of the word like bad MPQASRC Indicates the opinion source in the sentence like It MPQASD Direct subject expression in the sentence like said Result : No evident correlation between number of polar words and the rank of the post Authors use equal distribution of positive and negative words while expressing agreement/disagreement. PostsAgreement PostsDisagreement Posts Positive words-0.008240.012647 Negative words-0.010240.01392 Slide 7 Experiment 2 : Readability Measure Intuition : Do the posts that are more readable/formal gain higher scores? Tool Flesch Toolkit to analyze the Flesch Readability measure for each post. Calculated Pearsons coefficient between the labeled score and Flesch score for each of the posts. Result : High correlation - the more formal the language of a post, the more is the points associated with it. Eg 1 : good times...bring it back ! -------------=-=-=-=-=-=-=-=-=- =-=-=-==-=-=- )))))))))))) [Flesch 0, Labeled points - 1] Eg 2 : Vegetables is often seen as more healthy than eating meat. [Flesch 93.12, Labeled points 29 (max)] PostsAgreement PostsDisagreement Posts Pearsons correlation for flesch readability 0.2069740.169236 Slide 8 Experiment 3 : Emoticon analysis Intuition : Do Emoticons in agreement/disagreement posts have any correlation with their labeled scores? Tool CMU Ark Tagger [Stanford Parser doesnt scale well]. Pearsons coefficient between the labeled score and number of +ve/-ve emoticons for agreement/disagreement posts. Result : High correlation between number of emoticons and rank of disagreement posts. Analysis : authors tend to use expressive emoticons like smiles to give a sarcastic opinion regarding a particular argument. Hey! Whats that supposed to mean?;), Sure If you say so :P. PostsAgreement PostsDisagreement Posts Positive emoticons-0.023750.38943 Negative emoticons-0.0035270.03421 Slide 9 Experiment 4 : Dependency Parse Intuition : Do highly ranked agreement/disagreement posts depict a popular dependency pattern? Agreement posts tend to express an agreement early on in the post, while disagreement is mild. Tool Stanford Parser Syntactic and Dependency Parse of the posts. Result: A lot of highly ranked agreement posts showed a popular dependency pattern as follows that begins with - I->nsubj->+ve [I agree to, I like your point, I up-voted your argument] I have to agree. Blah blah I->nsubj->have->xcomp->agree->End I->nsubj->+ve->xcomp->+ve->End Stanford Parser + ExtractDependencies Code to traverse PRP to PRP$ Sentiwordnet PostsAgreement Posts Pearsons coeff with I->nsubj->+ve pattern0.252146 Slide 10 Author starting a neutral post? Time of entry into discussion? Average number of times an author participates in a thread? Author participating in agreement/disagreement discussions? Finding the needle - behavioral features . Slide 11 Which Authors get the highest rank? -1 Intuition : To find if average number of times an author participates in a thread has a correlation with his ranking? Pearsons coefficient Average number of times an author participates in a thread. 0.489 Result : There is a pretty evident positive correlation of an authors points to the number of times he participates in the discussion posts per thread. Slide 12 Which Authors get the highest rank?-2 Intuition : To find if authors who participate in some kind of discussion/ or start a new thread get a high rank ? Pearsons coefficient Authors who agree 0.847 Authors who disagree0.770 Authors who start a new thread. 0.60 Result : Rating of authors who agree > Rating of authors who disagree more > Rating of authors who start a new debate. Authors who participate more in discussions are more popular. Slide 13 Which Authors get the highest rank?-3 Intuition : To find if a authors that participate early/late in discussion fetch more ranking? Pearsons coefficient Authors who participate early 0.1990 Authors who participate late-0.00358 Result : Authors participating late in discussion are likely to have higher ranking. By Intuition, authors who come late in discussion already know the opinion bias. Participating early doesnt help in ranking Slide 14 Get the Ranking of Authors w.r.t features Trained a linear regression model using Wekas Libsvm and got a predicted ranking of all authors based on the features. Got a correlation coefficient by comparing these rankings vs the gold standard rankings. SVMs Correlation Coefficient Gold Standard Rankings/ Predicted Rankings. 0.300 Result : The feature vector set shows a decent correlation with the actual rankings. Slide 15 Future Work In this project, I essentially looked at some of the structural and behavioral features The opinion finder tool also tells whether it is a subjective or objective. One of the future Experiments to find if there exists a correlation between subj/obj sentences and score of post? Does the length of the post matter? Going forward - consolidate all these features and results in the database and make it available as an open-source dataset Slide 16 Thank You!