1 Indo WordNet A WordNet for Hindi Centre for Technology Development for Indian Languages Computer Science and Engineering Department, IIT Bombay

2 Introduction WordNet – A lexical database Searching the dictionary conceptually Different organizing principles for different syntactic categories Synsets or the Synonymy Sets are the basic building blocks Lexical knowledge base is the heart of any intelligent information processing system

3 Semantic relations in WordNet Synonymy Hypernymy / Hyponymy Antonymy Meronymy / Holonymy Gradation Entailment Troponymy

4 Synonymy True synonyms are rare Synonymy related to a context { Gar ‚ kmara } { Gar ‚ Aavaasa } { Gar ‚ janmakuMDlaIya sqaana } { Gar ‚ svadoSa }

5 How to create a synset Word is chosen from a dictionary The particular concept is made explicit Other synonyms according to that concept are taken Definition,example & ontology are given Parts of speech are given

6 Principles adopted in creating synsets Minimaility the minimal set of words to make the concept unique Coverage the maximal set of words- ordered by frequency in the corpus- to include all possible words standing for the sense Replaceability the example sentence should be such that the most frequent words in the synset can replace one another in the sentence without altering the sense

7 Example of a Synset in Wordnet Example of a nominal concept Saor Saor, baaGa, vyaaGa`, naahr : iballaI kI jaait ka ek bahut baD,a AaOr BayaMkr, p``isaw ihMsak pSau “ iSakarI ko AcaUk inaSaanao nao Saor kao Gaayala kr idyaa ” Saor, Saorao - SaayarI : ga,ja,la ko dao carNa “ ]sanao Saor saunaakr sabakI vaahvaahI laUTI ” Saor, vaIrpuÉYa,, bahadur, narvaIr, narvyaaGa``, SaUr, SaUrvaIr, saUrmaa, vaIr : vah vaIrpuÉYa, jaao balavaana hao yaa saahsapUNa- yaa vaIrtapUNa- kaya- krta hao “ iSavaajaI kao maharaYT/ ka Saor kha jaata hO ”

8 Semantic Relations Hypernymy and Hyponymy Relation between word meaning (synsets) X is a hyponym of Y if X is a kind of Y Hyponymy is transitive and asymmetrical Hypernymy is inverse of Hyponymy lion  animal  living entity  entity Saor  pSau  sajaIva  Aist%va

9 Semantic Relations (Contd…) Antonymy Oppositeness in meaning Relation between word forms Meronymy and Holonymy Part-whole relation, branch is a part of tree X is a meronymy of Y if X is a part of Y Meronym is transitive and asymmetrical Holonymy is inverse relation of Meronymy

10 Troponym and Entailment Entailment { Kra-Ta laonaa – saaonaa £ Troponym { laÐgaD,anaa ‚ kdmatala krnaa – calanaa £ ¡ fusafusaanaa – baaolanaa £

11 Cross Parts of Speech Linkage  linkages between Nominal and Verbal concepts Ability Link specifies the inherited features of a nominal concept Capability Link specifies the acquired features of a nominal concept Function Link specifies the function of a nominal concept

12 Cross Parts of Speech Linkage (Contd…) jaMtu Ability Link calanaa tOrn aa maClaI Capability Link tOrna a baaol anaa taota Function Link calan aa vaah na isalan aa isalaaš maSaIn a

13 Cross Parts of Speech Linkage (Contd…)  linkage between nominal and adjective concept Attribute Link denotes the properties of a noun baaGamaaMsaaharI inayattapIstnapayaI jaMtu Noun Adjective Attribute

14 Cross Parts of Speech Linkage (Contd…) Derived from  specifies the root form from which a particular word is derived  this relation can go from noun to adjective or vice versa, noun to verb and adjective to verb  aims to handle derivational morphology Aaturta Aatur AiBamaMi~tAiBamaM~Na baityaanaa baat gamaa-naagama- Derived from Noun Verb Adjective

15 Gloss AQyayana kxa Hyponymy Aavaasa, inavaasa Sayana kxa rsaao [-Gar Gar, gaRh manauYyaaoM ka Cayaa huAa vah sqaana jaao dIvaaraoM sao Gaor kr banaayaa jaata hO Aitiqa gaRh baramad a Aa^M gana AaEama JaaopD,I saMr cana a Meronymy Hyponymy MeronymyMeronymy Hypernymy WordNet Sub-Graph