?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adc&rft.title=Thumbs+up+or+thumbs+down%3F+Semantic+orientation+applied+to+unsupervised+classification+of+reviews&rft.creator=Turney%2C+Peter+D.&rft.subject=Artificial+Intelligence&rft.subject=Language&rft.subject=Machine+Learning&rft.subject=Statistical+Models&rft.description=This+paper+presents+a+simple+unsupervised+learning+algorithm+for+classifying+reviews+as+recommended+(thumbs+up)+or+not+recommended+(thumbs+down).+The+classification+of+a+review+is+predicted+by+the+average+semantic+orientation+of+the+phrases+in+the+review+that+contain+adjectives+or+adverbs.+A+phrase+has+a+positive+semantic+orientation+when+it+has+good+associations+(e.g.%2C+%22subtle+nuances%22)+and+a+negative+semantic+orientation+when+it+has+bad+associations+(e.g.%2C+%22very+cavalier%22).+In+this+paper%2C+the+semantic+orientation+of+a+phrase+is+calculated+as+the+mutual+information+between+the+given+phrase+and+the+word+%22excellent%22+minus+the+mutual+information+between+the+given+phrase+and+the+word+%22poor%22.+A+review+is+classified+as+recommended+if+the+average+semantic+orientation+of+its+phrases+is+positive.+The+algorithm+achieves+an+average+accuracy+of+74%25+when+evaluated+on+410+reviews+from+Epinions%2C+sampled+from+four+different+domains+(reviews+of+automobiles%2C+banks%2C+movies%2C+and+travel+destinations).+The+accuracy+ranges+from+84%25+for+automobile+reviews+to+66%25+for+movie+reviews.+%0A%0A&rft.date=2002&rft.type=Conference+Paper&rft.type=PeerReviewed&rft.format=application%2Fpostscript&rft.identifier=http%3A%2F%2Fcogprints.org%2F2321%2F1%2Fturney-acl02-final.ps&rft.format=application%2Fpdf&rft.identifier=http%3A%2F%2Fcogprints.org%2F2321%2F5%2Fturney-acl02-final.pdf&rft.identifier=++Turney%2C+Peter+D.++(2002)+Thumbs+up+or+thumbs+down%3F+Semantic+orientation+applied+to+unsupervised+classification+of+reviews.++%5BConference+Paper%5D+++++&rft.relation=http%3A%2F%2Fcogprints.org%2F2321%2F