Named Entity Linking Flashcards
Why is NEL important as well as NER
NER tells us nothing about the entities. We are able to learn information about entities and their relationships
What is a key resource to be able to perform NEL
Knowledge base
What are some key knowledge bases for NEL (3)
wikipedia, freebase, Unified medical language system
what do we find about entities using wikipedia
each entity has an article
what do we find about entities using freebase
a knowledge graph, where each entity is a node
what is the task of NEL
link mention to corresponding entity in knowledge base
what is an entity embedding
just like word embedding, we can learn entity embeddings
what is the general approach to NEL (2)
1, generate candidates
2, rank candidates
what are the approaches to generating candidates
dictionary base, rule based, similarity, information retrieval
what are the approaches the candidate ranking
classification
neural based
how do we generate candidates
scan every page in Wikipedia, extract entity and alias to create an entity-alias dictionary that gives us p(entity|alias)
describe local candidate ranking
for each mention m in context c, we have a set of E candidates. Get the highest score from bilstm
describe global approach to candidate ranking
coherency between terms. predict entities for all mentions using crf.
what is different about the way we use crf for candidate ranking compared to NER
dont use linear chain, use fully connected graph
what are the downstream applications for NEL
information retrieval, content analysis, question answering, KB construction
