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Sentiment Analysis based on Appraisal Theory and Functional Local ...

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21<br />

Turney [170] determined whether words are positive or negative <strong>and</strong> how str<strong>on</strong>g<br />

the evaluati<strong>on</strong> is by computing the words’ pointwise mutual informati<strong>on</strong> for their cooccurrence<br />

with a positive seed word (“poor”) <strong>and</strong> a negative seed word (“negative”).<br />

They call this value the word’s semantic orientati<strong>on</strong>.<br />

Turney’s software scanned<br />

through a review looking for phrases that match certain part of speech patterns,<br />

computed the semantic orientati<strong>on</strong> of those phrases, <strong>and</strong> added up the semantic<br />

orientati<strong>on</strong> of all of those phrases to compute the orientati<strong>on</strong> of a review. He achieved<br />

74% accuracy classifying a corpus of product reviews. In his later work, [171] he<br />

applied semantic orientati<strong>on</strong> to the task of lexic<strong>on</strong> building because of efficiency issues<br />

in using the internet to look up lots of unique phrases from many reviews.<br />

Harb<br />

et al. [65] performed blog classificati<strong>on</strong> by starting with the same seed adjectives <strong>and</strong><br />

used Google’s search engine to create associati<strong>on</strong> rules that find more. They then<br />

counted the numbers of positive versus negative adjectives in a document to classify<br />

the documents.<br />

They achieved 0.717 F 1 score identifying positive documents <strong>and</strong><br />

0.626 F 1 score identifying negative documents.<br />

Whitelaw, Garg, <strong>and</strong> Argam<strong>on</strong> [173] augmented bag-of-words classificati<strong>on</strong><br />

with a technique which performed shallow parsing to find opini<strong>on</strong> phrases, classified<br />

by orientati<strong>on</strong> <strong>and</strong> by a tax<strong>on</strong>omy of attitude types from appraisal theory [110],<br />

specified by a h<strong>and</strong>-c<strong>on</strong>structed attitude lexic<strong>on</strong>. Text classificati<strong>on</strong> was performed<br />

using a support vector machine, <strong>and</strong> the feature vector for each corpus included word<br />

frequencies (for the bag-of-words), <strong>and</strong> the percentage of appraisal groups that were<br />

classified at each locati<strong>on</strong> in the attitude tax<strong>on</strong>omy, with particular orientati<strong>on</strong>s.<br />

They achieved 90.2% accuracy classifying the movie reviews in Pang et al.’s [134]<br />

corpus.<br />

Snyder <strong>and</strong> Barzilay [155] extended the problem of review classificati<strong>on</strong> to<br />

reviews that cover several different dimensi<strong>on</strong>s of the product being reviewed. They

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