RussNet:
wordnet
for Russian
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RussNet:
wordnet
for Russian
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Relations in RussNetThe list of semantic relations presented in RussNet is based mostly on Princeton WordNet Lexical and Conceptual Relations, and EuroWordNet Language-Internal Relations. But there are some differences in treatment of synonymy, hyponymy, antonymy, and role_realtions. Also a set of new relations that combine semantic features with grammatical or derivational ones was introduced, such as relations between members of aspect pairs, between neutral words and their expressive derivatives etc. Mostly these are relations between members of synsets (‘literals’) rather than synsets themselves. Relations between synsets:
Relations between literals:
SYNONYMYSynonymy is a fundamental relation, on which all wordnets, and RussNet in particular, are based. Sets of synonyms (so called synsets) are regarded as the main structural units of wordnets. There are two different ways to define synonymy:
This complex approach to the synonymy definition is supported by Russian lexicographic tradition [Apresjan 1999, Evgenjeva 1970, and Babenko 1999]. Thus, in RussNet the term SYNONYMY is generally used to refer to the relation between words, compound words or collocations
Synonymy is a symmetric relation, i.e. if A is synonymous to B, B is synonymous to A. In practice, the relation of synonymy may be set up as a hypothesis on the basis of lexicographer’s intuitions or some dictionary of synonyms, then it should be verified with the synonymic definitions from the explanatory dictionary (see the Definition Analysis for details), and finally it should pass the standard implicative tests of the following type [Cruse 1986, Vossen 1998 ]: Word1 in Contextc entails and is entailed by Word2 in Contextc
e.g.: Word1 = гиппопотам e.g.: Word1 = роза
For better structuring we set order into the synset and regard one of its members as a representative of the whole synset, its dominant literal. Usually it is a literal without (or with minimum) stylistic and expressive colouring. In synset structuring we rely upon the frequency data: being a neutral term, dominant is expected to occur in texts more often then other members of the corresponding synset. We foresee the correlation between two modes of synset organization: from frequent to infrequent, and from the dominant through its absolute synonyms and duplicates to the stylistic and expressive synonyms. e.g.: глаз1 - has relative frequency about 1329 ipm, Thus the synset is structured as follows: {глаз1, око (высок.), зенки (прост.), глазик1 (мелиор.), глазок2 (мелиор.)} HYPONYMY / HYPERONYMYHyponymy or IS_A relation plays a crucial role in constructing of lexical databases and ontologies, because it allows to organize data in hierarchical structures (trees), within which the top-down inheritance of semantic features are shown. The meaning of the superordinate term (‘parent’, ‘hyperonym’), is included into the meanings of all its subordinates (‘children’, ‘hyponyms’), e. g., words like chair, sofa, bench etc. contain as a part of their meanings a pointer to the meaning of seat. Hyponymy is a transitive relation: e.g. being a kind of {цветок}, {роза} has inherited not only all semantic features of {цветок}, but also that of its superordinates: {растение}, {живой организм}, etc. Within RussNet we use the term HYPONYMY to refer to the relation of semantic inclusion:
The general implicative test sentence for hyponymy is unidirectional: Word1 in Contextc entails but is not entailed by Word2 in Contextc e.g.: Word1 = идти What concerns hyponymy, in RussNet we allow the existence of multi-parent relations, i.e. one synset may have several hyperonyms. E.g., actress “female actor” is subordinated to both actor and woman. Though it is rather difficult to deal with multiple inheritances within databases, we believe that it helps us to reflect the real structure of semantic relations within language. We suppose that in future the existence of multi-parent relations accompanied with introduction of special relation attributes may help us to distinguish between following types of HYPONYMY:
ANTONYMYAlthough in Princeton WN antonymy is regarded as a relation between words rather than synsets, in RussNet antonymy is considered to be one of the semantic relations between synsets. Yet we by no means are to reject the differentiation of direct and indirect antonymy. We suppose that setting order into a synset (for details see SYNONYMY chapter) helps us to manage this problem adequately. As Word Association Norms show, in Russian it is usually synset representatives (‘dominant literals’) that are related by antonymy directly, all other members of synsets are opposed through this pair, i.e. indirectly. E.g., большой is strongly associated with маленький, маленький is associated with большой, while небольшой is associated first of all with маленький, its association with большой is rather weak. But there still is a possibility that several pairs of direct antonyms may appear in the frame of two synsets, like in English large <-> small, big <-> little. However, our data proves this phenomenon is not that characteristic for Russian. Antonymy is a symmetric relation, i.e. if A is antonymous to B, B is antonymous to A. For verification of antonymy we apply bidirectional implicative test sentences with negation: Word1 in Contextc entails not-Word2 in Contextc Word2 in Contextc entails not-Word1 in Contextc e.g.: Word1 = подтверждать,
CONVERSIONWe believe it is reasonable to differentiate such oppositions as, for example, покупать - продавать, муж - жена from antonymous ones. We treat CONVERSION as a separate relation that differs from other types of opposition in that:
E.g., покупать and продавать are converse terms because they describe the same situation of exchanging goods for money or its equivalent, покупать - from the viewpoint of buyer, while продавать - from the viewpoint of seller. {Покупать} is a hyponym of {получать, приобретать}, while {продавать} is subordinated to {отдавать, передавать2}. MERONYMY / HOLONYMYMeronymy or HAS_A relation links synsets denoting wholes with that denoting their parts. Though meronyms can sometimes be arranged in hierarchical structures (e.g., body parts), usually they are rather incorporated into a net-like structures than trees (e. g., point may be a part of knife, as well as a part of pencil, pin etc.) Unlike the hyponymy, transitivity of meronymy is quite limited: e.g., ручка - часть двери, дверь - часть дома are normal, but it is quite odd to say ручка - часть дома. Meronymy is an asymmetric relation, it may not be always reversible to holonymy: e.g., whereas a forest is not a forest unless it consists of trees, a tree does not necessarily grow in a forest (it may be a street or a desert) [Cruse 1986]. In RussNet following types of MERONYMY are distinguished:
ENTAILMENTENTAILMENT, based on the logical relation of strict implication, is one of the prominent relations specific mostly for verbs and their derivatives. According to [Fellbaum, 1998], “the different relations that organize the verbs can be cast in terms of one overarching principle, lexical entailment”. Two basic kinds of lexical entailment can be distinguished: one involves ‘temporal inclusion’ (the two situations referred to by the verbs in the relation partially or totally overlap); the other involves ‘temporal exclusion’ (the two situations are variously temporally disjoint). These temporal relationships between verbs are taken as a basis for a further distinction of four kinds of entailment:
Within Princeton WN (a1) is referred to as TROPONYMY, In EuroWordNet data related to the WN 1.5 entailment relation are encoded in a different a way [Alonge, 1996]: In RussNet we encode data related to the entailment principle in a following way: BACKWARD PRESUPPOSITIONThus, within RussNet we apply the term BACKWARD PRESUPPOSITION to the entailment relations between synsets that:
E.g.: on the one hand, отвечать temporally succeeds спрашивать, on the other hand it presupposes nothing but спрашивать as its necessary starting condition. SUBEVENT / IS_SUBEVENTWithin RussNet we apply the term SUBEVENT / IS_SUBEVENT to the entailment relations between synsets that:
For verifying SUBEVENT / IS_SUBEVENTrelations we use test sentences of the following type: Word1 in Contextc, but not Word2 in Contextc (false) CAUSATIONThe term CAUSATION is used to indicate the entailment relation between synsets that:
All kinds of ENTAILMENT are unidirectionalrelations in that if Word1 entails Word2 it does not mean that Word2 necessarily entails Word1. Death is not necessarily a result of killing (убить CAUSE умереть, but not *умереть IS_CAUSED убить), while paying is always a part of buying (платить IS_SUBEVENT покупать, and покупать SUBEVENT платить). INCHOATIVE / TERMINATIVE‘INCHOATIVE'(BEGIN) is a semantic relation between verb synsets denoting some state, event, or action and the beginning of this state, event or action, e.g.: {полюбить, возлюбить (устар.)} BEGIN {любить1}. Its counterpart, ‘TERMINATIVE'(END) is a semantic relation opposing some state, event, or action to its ending, e.g.: {разлюбить, охладеть2} END {бить1} BEGIN/END are complex relations, bordering upon antonymy, backward presupposition and aspect opposition. Firstly, having the opposite direction, inchoative term may be opposed to terminative one as its reversive, e.g.: {полюбить, возлюбить (устар.)} <-> {разлюбить, охладеть2}. Secondly, both inchoative and terminative terms presuppose being in the state, e.g. {полюбить, возлюбить (устар.)} => {любить1}, {разлюбить, охладеть2} => {любить1}, though being in some state may assume no inherent beginning or ending ?<= {любить1} =>?. Thirdly, ending of some state may resemble its culminating point, thus being associated with perfect aspect category. INVOLVED_RELATIONS / ROLE_RELATIONSINVOLVED (and its counterpart ROLE) is a set of relations linking verb synsets to other PoS: nouns, adjectives and adverbs, including
As opposed to EuroWordNet we use this terms not only to encode the data concerning sense of other words strongly involved into a verb sense [Alonge, 1993], but also to demonstrate probable argument structures of verbs. We generalize EWN treatment of these relations so that INVOLVED/ROLE refer to verb-to-class relations, with verb-to-word relations being its extreme case, when class contains only 1 member. E.g.: {беседовать2, говорить2} INVOLVED_AGENT + {человек, лицо3}; {гукать2} INVOLVED_ AGENT {младенец}. {Младенец} is linked to a single synset {гукать2}, while + {человек, лицо3} refers not only to synset itself, but also to all its hyponyms, thus covering a class of synsets being probable agent arguments of {беседовать2, говорить2}. INVOLVED relations play crucial role in valency frames description (for details see Verbs chapter). DERIVATIONAL_SYNONYMYIt is a relation between neutral words and their expressive derivatives. They denote the same concept, but contrast in the speaker’s attitude to the concept. As derivatives and corresponding stem words differ in style, they are not interchangeable in context, e. g. старик (old man) - старикан, старикашка (impolite address to an old man), дом (house) - домик1 (house to which the speaker has positive emotions). Derivatives are included into the same synset as corresponding stem words, e.g. {старик, старикан, старикашка}, but with special expressive attributes: e.g. домик will have (мелиор.) or X_EXPRESSES_ POSITIVE_EMOTIONS, while старикан and старикашка will be marked by (пейор.) or X_EXPRESSES_ NEGATIVE_EMOTIONS. DERIVATIONAL_HYPONYMYLike Derivational_Synonymy, DERIVATIONAL_HYPONYMY is a relation between cognate literals (nouns or adjectives). But in this case a derivative and corresponding stem-word denote the concepts that slightly differ from each other, e.g., дом (house) - домик2 (small house), дом (house) - домина (big house). The clear sense component is added by derivational affix to the stem-word meaning, so that the resulting word couldn't be regarded as its expressive synonym. That is why we treat such pairs as derivational hyperonym - derivational hyponym, and include into different synsets. According to the meaning component added by derivational affix we divide DERIVATIONAL_HYPONYMY into several types:
DERIVATIONAL_INVOLVED / DERIVATIONAL_ROLE_RELATIONSDERIVATIONAL_INVOLVED_RELATIONS are established to link a verb to its derivatives, designating action participants. These are relations between literals, that implies strong semantic incorporation supported by derivational motivation:
e.g.: сеять DER_INVOLVED_OBJECT сеянец, These are unidirectional relations. Introduction of Derivational_INVOLVED_Relations allows us to present the inheritance of the argument structure and selectional restrictions of stem verbs by their derivatives, e.g.: бороться за правое дело => борьба за правое дело => борец за правое дело. ASPECT_OPPOSITIONAspect is a category specific for verbal derivatives in highly inflectional languages, like Russian and other Slavonic. Aspect pairs interact in a complex manner: on the one hand, they look like very close synonyms, though on the other hand, they realise a very important semantic oppositions, concerning ‘Aktionarten’ differentiation [Vendler 1967], such as activity - action. Thus, in RussNet IMPERFECT/PERFECT are relations that have semantic-grammatical nature and links verb literals denoting temporarily unbounded event, action, or state characterized by multiple or unspecified recurrence, on the on hand, with cognate literals, denoting temporarily bounded event, action, or state characterized by accomplishment of inherent culminating point, on the other hand.
E.g.: делать PERFECT сделать, Aspect opposition has obligatory formal representation: derivational affixes -ыва-, с-, -ну- etc. |
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