Socio-Affective Computing Volume 1 SeriesEditor AmirHussain,UniversityofStirling,Stirling,UK CoEditor ErikCambria,NanyangTechnologicalUniversity,Singapore This exciting Book Series aims to publish state-of-the-art research on socially intelligent,affectiveandmultimodalhuman-machineinteractionandsystems.Itwill emphasizetheroleofaffectinsocialinteractionsandthehumanisticsideofaffective computing by promoting publications at the cross-roads between engineering and human sciences (including biological, social and cultural aspects of human life). Three broad domains of social and affective computing will be covered by the book series: (1) social computing, (2) affective computing, and (3) interplay of the first two domains(forexample,augmentingsocialinteractionthroughaffective computing).Examplesofthefirstdomainwillincludebutnotlimitedto:alltypesof social interactionsthatcontribute to the meaning,interestand richnessof our daily life, for example, information produced by a group of people used to provide or enhance the functioningof a system. Examplesof the second domain will include, but not limited to: computational and psychological models of emotions, bodily manifestations of affect (facial expressions, posture, behavior, physiology), and affective interfaces and applications (dialogue systems, games, learning etc.). This series will publish works of the highest quality that advance the understanding and practical application of social and affective computing techniques. Research monographs, introductory and advanced level textbooks, volume editions and proceedingswillbeconsidered. Moreinformationaboutthisseriesat http://www.springer.com/series/13199 Erik Cambria • Amir Hussain Sentic Computing A Common-Sense-Based Framework for Concept-Level Sentiment Analysis 123 ErikCambria AmirHussain SchoolofComputerEngineering ComputingScienceandMathematics NanyangTechnologicalUniversity UniversityofStirling Singapore,Singapore Stirling,UK Socio-AffectiveComputing ISBN978-3-319-23653-7 ISBN978-3-319-23654-4 (eBook) DOI10.1007/978-3-319-23654-4 LibraryofCongressControlNumber:2015950064 SpringerChamHeidelbergNewYorkDordrechtLondon ©SpringerInternationalPublishingSwitzerland2015 Thisworkissubjecttocopyright.AllrightsarereservedbythePublisher, whetherthewholeorpartof thematerialisconcerned,specificallytherightsoftranslation,reprinting,reuseofillustrations,recitation, broadcasting, reproductiononmicrofilmsorinanyotherphysicalway,andtransmissionorinformation storageandretrieval, electronic adaptation, computersoftware,orbysimilarordissimilarmethodology nowknownorhereafterdeveloped. Theuseofgeneraldescriptivenames,registerednames,trademarks,servicemarks,etc.inthispublication doesnotimply,evenintheabsenceofaspecificstatement,thatsuchnamesareexemptfromtherelevant protectivelawsandregulationsandthereforefreeforgeneraluse. Thepublisher,theauthorsandtheeditorsaresafetoassumethattheadviceandinformationinthisbook arebelieved tobetrue andaccurate atthe date ofpublication. Neither thepublisher northeauthors or theeditors giveawarranty, express orimplied, withrespect tothematerial contained herein orforany errorsoromissionsthatmayhavebeenmade. Printedonacid-freepaper Springer International Publishing AG Switzerland is part of Springer Science+Business Media (www. springer.com) In memory of Dustin, A man with a great mind and a big heart. Foreword Itwasa particularjoytomehavingbeenaskedtowritea fewwordsforthissecond book on sentic computing - the first book published in 2012, gave me immense inspirationwhichhasgrippedmeeversince.Thisalsomakesitarelativelyeasybet thatitwillcontinueitswaytoastandardreferencethatwillhelpchangethewaywe approachsentiment,emotion,andaffectinnaturallanguageprocessingandbeyond. Whileapproachestointegrateemotionalaspectsinnaturallanguageunderstand- ingdatebacktotheearly1980ssuchasinDyer’sworkonIn-DepthUnderstanding, at the very turn of the last millennium,there was still very limited literature in this direction. It was about 3 years after Picard’s 1997 field-defining book on Affective Computing and one more after the first paper on Recognizing Emotion in Speech by Dellaert, Polzin, and Waibel and a similar one by Cowie and Douglas-Cowie that followed ground-laying work, including by Scherer and colleagues on vocal expression of emotion and earlier work on synthesizing emotion in speech when a globalindustrialplayerplacedanorderforastudywhetherwecanenablecomputers to recognize users’ emotional factors in order to make human-computerdialogues morenatural. After first attempts to grasp emotion from facial expression, our team realized that computer vision was not truly ready back then for “in the wild” processing. Thus, the thought came to mind to train our one-pass top-down natural language understandingengineto recognizeemotionfromspeechinstead. In doingso, I was left with two options: train the statistical language model or the acoustic model to recognize basic emotions rather than understand spoken content. I decided to do both and, alas, it worked– at least to some degree.However,when I presented this newability,theusualaudienceresponsewas,mainlyalongthelinesof“Interesting, butwhatistheapplication?”Sincethen,amajorchangeofmindhastakenplace:it isbyandlargeagreedthattakingintoaccountemotionsiskeyfornaturallanguage processingandunderstanding,especiallyfortaskssuchassentimentanalysis. As a consequence,these days, severalhundredpapersdealingwith the topic ap- pearannually,andonefindsseveralthousandcitationseachyearin thisfield which is still gaining momentum and expected to be nothing less than a game-changing factor in addressing future computing challenges, such as when mining opinion, vii viii Foreword retrieving information, or interacting with technical systems. Hardly surprisingly, the commercial interest is ever rising, and first products-have already found their wayintobroadpublicawareness. The lion’s share of today’s work aimed at dealing with analyzing emotion and sentiment in spoken and written language, is based on statistical word co- occurrences. The principle is described in Joachim’s 1996 work on text catego- rization representing a document as a “bag-of-words” in a vector space. Different normalizations are named, and sequences of n words or characters (‘n-grams’) have since been applied successfully in similar fashion. With the advent of “big data,” recent approaches, such as by Google, translate the single words into (their individual) vectors by (some form of) soft clustering. This reflects each word’s relation to the other words in the vocabulary as added information. However, such approaches have reached a certain glass ceiling over the years as they are very limited in taking inspiration from how the human brain processes both emotions (byexploitinganemotionmodel)andmeaning(byworkingatthesemantic/concept levelratherthanatthesyntactic/wordlevel)toperformnaturallanguageprocessing taskssuchasinformationextractionandsentimentanalysis. This is what Sentic Computing is all about. Targeting the higher hanging fruits bynotmissingtheimportanceofaimingtoemulatethebrain’sdescribedprocessing ofemotionsandmeaning,itprovidesaknowledge-basedapproachtoconcept-level sentimentanalysisthatiswellrootedinamulti-disciplinaryview.Theconsideration of a text as a bag-of-wordsis accordingly substituted by representing it as a “bag- of-concepts.” This embeds linguistics in an elegant form beyond mere statistics, enrichingtherepresentationoftextbythedependencyrelationbetweenclauses.The bookguidesitsreadersfromthestudent-levelonwardsinaningeniousfashion,from an introduction and background knowledge (not only on sentiment analysis and opinionmining but also commonsense) to the core piece – SenticNet (introducing the acquisition and representation of knowledge as well as reasoning) to concept- level sentiment analysis. It then exemplifiesthese ideas by three excellently picked applications in the domains of the social web, human-computerinteraction, and e- health systems before concluding remarks. Thus, besides providing the essential comprehensionof the basicsof the field in a smoothandveryenjoyableway, itnot only manages to take the reader to the next level but introduces genuine novelty of utmost valuable inspiration to any expert in the field. In fact, it makes a major contribution to the next generation of emotionally intelligent computer systems. Do not be surprised catching yourself reasoning about sentiment and opinions in a whole new way even in your “non-tech” life. It remains to say that I am truly lookingforwardtothevolumestofollowthisonethatkicksofftheseriesonSocio- Affective Computing edited by the authors – and sets the bar utmost high for all aspiringreaders. ImperialCollege,London,UK BjörnW. Schuller July2015 President,Associationforthe Advancement ofAffectiveComputing(AAAC) Editor-in-Chief:IEEETransactions onAffectiveComputing Preface The opportunity to capture the opinions of the general public has raised growing interest both within the scientific community, leading to many exciting open challenges, and in the business world due to the remarkable range of benefits envisaged,includingfrommarketing,businessintelligenceandfinancialprediction. Mining opinions and sentiments from natural language, however, is an extremely difficulttaskasitinvolvesadeepunderstandingofmostoftheexplicitandimplicit, regular and irregular, syntactical and semantic rules appropriate of a language. Existing approaches to sentiment analysis mainly rely on parts of text in which opinions are explicitly expressed such as polarity terms, affect words, and their co-occurrence frequencies. However, opinions and sentiments are often conveyed implicitly through latent semantics, which make purely syntactical approaches ineffective. Concept-levelapproaches, instead, use Web ontologiesor semantic networks to accomplish semantic text analysis. This helps the system grasp the conceptual and affectiveinformationassociatedwithnaturallanguageopinions.Byrelyingonlarge semanticknowledgebases,suchapproachesstepawayfromblindlyusingkeywords andwordco-occurrencecountsandinsteadrelyontheimplicitmeaning/featuresas- sociated with natural language concepts. Superior to purely syntactical techniques, concept-based approaches can detect subtly expressed sentiments. Concept-based approaches, in fact, can analyze multi-word expressions that do not explicitly conveyemotion,butare relatedto conceptsthatdoso. Senticcomputingisapioneeringmulti-disciplinaryapproachtonaturallanguage processing and understanding at the crossroads between affective computing, information extraction, and common-sense reasoning, and exploits both computer and human sciences to better interpret and process social information on the Web. In sentic computing, whose term derives from the Latin “sentire” (root of words such as sentiment and sentience) and “sensus” (as in common sense), the analysis of natural language is based on common-sense reasoning tools, which enable the analysis of text not only at the document, page, or paragraph level but also at the sentence,clause,andconceptlevel. ix
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