7,548 research outputs found
Lexical acquisition in elementary science classes
The purpose of this study was to further researchers' understanding of lexical acquisition in the beginning primary schoolchild by investigating word learning in small-group elementary science classes. Two experiments were conducted to examine the role of semantic scaffolding (e.g., use of synonymous terms) and physical scaffolding (e.g., pointing to referents) in children's acquisition of novel property terms. Children's lexical knowledge was assessed using multiple tasks (naming, comprehension, and definitional). Children struggled to acquire meanings of adjectives without semantic or physical scaffolding (Experiment 1), but they were successful in acquiring extensive lexical knowledge when offered semantic scaffolding (Experiment 2). Experiment 2 also shows that semantic scaffolding used in combination with physical scaffolding helped children acquire novel adjectives and that children who correctly named pictures of adjectives had acquired definitions
Comparing knowledge sources for nominal anaphora resolution
We compare two ways of obtaining lexical knowledge for antecedent selection in other-anaphora
and definite noun phrase coreference. Specifically, we compare an algorithm that relies on links
encoded in the manually created lexical hierarchy WordNet and an algorithm that mines corpora
by means of shallow lexico-semantic patterns. As corpora we use the British National
Corpus (BNC), as well as the Web, which has not been previously used for this task. Our
results show that (a) the knowledge encoded in WordNet is often insufficient, especially for
anaphor-antecedent relations that exploit subjective or context-dependent knowledge; (b) for
other-anaphora, the Web-based method outperforms the WordNet-based method; (c) for definite
NP coreference, the Web-based method yields results comparable to those obtained using
WordNet over the whole dataset and outperforms the WordNet-based method on subsets of the
dataset; (d) in both case studies, the BNC-based method is worse than the other methods because
of data sparseness. Thus, in our studies, the Web-based method alleviated the lexical knowledge
gap often encountered in anaphora resolution, and handled examples with context-dependent relations
between anaphor and antecedent. Because it is inexpensive and needs no hand-modelling
of lexical knowledge, it is a promising knowledge source to integrate in anaphora resolution systems
Jumping Finite Automata for Tweet Comprehension
Every day, over one billion social media text messages are generated worldwide, which provides abundant information that can lead to improvements in lives of people through evidence-based decision making. Twitter is rich in such data but there are a number of technical challenges in comprehending tweets including ambiguity of the language used in tweets which is exacerbated in under resourced languages. This paper presents an approach based on Jumping Finite Automata for automatic comprehension of tweets. We construct a WordNet for the language of Kenya (WoLK) based on analysis of tweet structure, formalize the space of tweet variation and abstract the space on a Finite Automata. In addition, we present a software tool called Automata-Aided Tweet Comprehension (ATC) tool that takes raw tweets as input, preprocesses, recognise the syntax and extracts semantic information to 86% success rate
Web based knowledge extraction and consolidation for automatic ontology instantiation
The Web is probably the largest and richest information repository available today. Search engines are the common access routes to this valuable source. However, the role of these search engines is often limited to the retrieval of lists of potentially relevant documents. The burden of analysing the returned documents and identifying the knowledge of interest is therefore left to the user. The Artequakt system aims to deploy natural language tools to automatically ex-tract and consolidate knowledge from web documents and instantiate a given ontology, which dictates the type and form of knowledge to extract. Artequakt focuses on the domain of artists, and uses the harvested knowledge to gen-erate tailored biographies. This paper describes the latest developments of the system and discusses the problem of knowledge consolidation
Similarity of Semantic Relations
There are at least two kinds of similarity. Relational similarity is
correspondence between relations, in contrast with attributional similarity,
which is correspondence between attributes. When two words have a high
degree of attributional similarity, we call them synonyms. When two pairs
of words have a high degree of relational similarity, we say that their
relations are analogous. For example, the word pair mason:stone is analogous
to the pair carpenter:wood. This paper introduces Latent Relational Analysis (LRA),
a method for measuring relational similarity. LRA has potential applications in many
areas, including information extraction, word sense disambiguation,
and information retrieval. Recently the Vector Space Model (VSM) of information
retrieval has been adapted to measuring relational similarity,
achieving a score of 47% on a collection of 374 college-level multiple-choice
word analogy questions. In the VSM approach, the relation between a pair of words is
characterized by a vector of frequencies of predefined patterns in a large corpus.
LRA extends the VSM approach in three ways: (1) the patterns are derived automatically
from the corpus, (2) the Singular Value Decomposition (SVD) is used to smooth the frequency
data, and (3) automatically generated synonyms are used to explore variations of the
word pairs. LRA achieves 56% on the 374 analogy questions, statistically equivalent to the
average human score of 57%. On the related problem of classifying semantic relations, LRA
achieves similar gains over the VSM
A Real-Time N-Gram Approach to Choosing Synonyms Based on Context
Synonymy is an important part of all natural language but not all synonyms are created equal. Just because two words are synonymous, it usually doesnât mean they can always be interchanged. The problem that we attempt to address is that of near-synonymy and choosing the right word based purely on its surrounding words. This new computational method, unlike previous methods used on this problem, is capable of making multiple word suggestions which more accurately models human choice. It contains a large number of words, does not require training, and is able to be run in real-time. On previous testing data, when able to make multiple suggestions, it improved by over 17 percentage points on the previous best method and 4.5 percentage points on average, with a maximum of 14 percentage points, on the human annotators near-synonym choice. In addition this thesis also presents new synonym sets and human annotated test data that more accurately fits this problem
WordNet: An Electronic Lexical Reference System Based on Theories of Lexical Memory
Cet article fait la description de WordNet, systĂšme de rĂ©fĂ©rence Ă©lectronique, dont le dessin est basĂ© sur des thĂ©ories psycholinguistiques concernant la mĂ©moire lexicale et lâorganisation mentale des mots.Les noms, les verbes et les adjectifs anglais sont organisĂ©s en groupes synonymes (les « synsets »), chacun reprĂ©sentant un concept lexical. Trois relations principales â lâhyponymie, la mĂ©ronymie et lâantonymie â servent Ă Ă©tablir les rapports conceptuels entre les « synsets ». Les prĂ©suppositions qui lient les verbes sont indiquĂ©es ainsi que leurs contextes syntaxiques et sĂ©mantiques.En tĂąchant de miroiter lâorganisation mentale des concepts lexicaux, WordNet pourrait servir lâutilisateur sans formation en linguistique.This paper describes WordNet, an on-line lexical reference system whose design is based on psycholinguistic theories of human lexical organization and memory.English nouns, verbs, and adjectives are organized into synonym sets, each representing one underlying lexical concept. Synonym sets are then related via three principal conceptual relations: hyponymy, meronymy, and antonymy. Verbs are additionally specified for presupposition relations that hold among them, and for their most common semantic/syntactic frames.By attempting to mirror the organization of the mental lexicon, WordNet strives to serve the linguistically unsophisticated user
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