Relational Inference for Wikification
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Transcript of Relational Inference for Wikification
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Relational Inference for Wikification
Xiao Cheng and Dan RothUniversity of Illinois at Urbana-Champaign
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Wikification
Blumenthal (D) is a candidate for the U.S. Senate seat now held by Christopher Dodd (D), and he has held a commanding lead in the race since he entered it. But the Times report has the potential to fundamentally reshape the contest in the Nutmeg State.
Blumenthal (D) is a candidate for the U.S. Senate seat now held by Christopher Dodd (D), and he has held a commanding lead in the race since he entered it. But the Times report has the potential to fundamentally reshape the contest in the Nutmeg State.
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Applications
Knowledge Acquisition via Grounding Coreference Resolution
Learning-based multi-sieve co-reference resolution with knowledge (Ratinov et al. 2012)
Information Extraction Unsupervised relation discovery with sense disambiguation (Yao et al.
2012) Automatic Event Extraction with Structured Preference Modeling (Lu
and Roth, 2012 ) Text Classification
Gabrilovich and Markovitch, 2007; Chang et al., 2008 Entity Linking
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Ambiguity
Concepts outside of Wikipedia (NIL) Blumenthal ?
Variability
Scale Millions of labels
Challenges
Blumenthal (D) is a candidate for the U.S. Senate seat now held by Christopher Dodd (D), and he has held a commanding lead in the race since he entered it. But the Times report has the potential to fundamentally reshape the contest in the Nutmeg State.
ConnecticutCT
The Nutmeg StateTimesThe New York TimesThe Times
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State-of-the-art systems (Ratinov et al. 2011) can achieve the above with local and global statistical features Reaches bottleneck around 70%~ 85% F1 on non-wiki datasets What is missing?
Challenges
Blumenthal (D) is a candidate for the U.S. Senate seat now held by Christopher Dodd (D), and he has held a commanding lead in the race since he entered it. But the Times report has the potential to fundamentally reshape the contest in the Nutmeg State.
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, the of deposed , …
Motivating Example
Mubarak wife Egyptian President Hosni Mubarak
What are we missing with Bag of Words (BOW) models? Who is Mubarak?
Constraining interaction between concepts (Mubarak, wife, Hosni Mubarak)
Mubarak, the wife of deposed Egyptian President Hosni Mubarak, …
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Relational Inference for Wikification
Our contribution Identify key textual relations for Wikification A global inference framework to incorporate relational knowledge
Significant improvement over state-of-the-art systems
Mubarak, the wife of deposed Egyptian President Hosni Mubarak, …
(Mubarak, wife, Hosni Mubarak)
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Talk Outline
Why Wikification? Introduction
Motivation Approach
Wikification Pipeline Formulation Relational Analysis
Evaluation Result Entity Linking
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Mention Segmentation
Candidate Generation
Candidate Ranking
NIL Linking
Wikification
Mention Segmentatio
n
Candidate Generation
Candidate Ranking
Determine NILs
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Wikification Pipeline 1 - Mention Segmentation
...ousted long time Yugoslav President Slobodan Milošević in October. Mr. Milošević's Socialist Party…
sub-NP (Noun Phrase) chunks NER Regular expressions
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Wikification Pipeline 1 - Mention Segmentation
...ousted long time Yugoslav President Slobodan Milošević in October. Mr. Milošević's Socialist Party…
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Wikification Pipeline 2 - Candidate Generation
...ousted long time Yugoslav President Slobodan Milošević in October. Mr. Milošević's Socialist Party…
k ek4
1 Socialist_Party_(France)
2 Socialist_Party_(Portugal)
3 Socialist_Party_of_America
4 Socialist_Party_(Argentina)
…
k ek3
1 Slobodan_Milošević
2 Milošević_(surname)
3 Boki_Milošević
4 Alexander_Milošević
…
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Wikification Pipeline 3 - Candidate Ranking
...ousted long time Yugoslav President Slobodan Milošević in October. Mr. Milošević's Socialist Party…
k ek4 sk
4
1 Socialist_Party_(France) 0.23
2 Socialist_Party_(Portugal) 0.16
3 Socialist_Party_of_America 0.07
4 Socialist_Party_(Argentina) 0.06
…
k ek3 sk
3
1 Slobodan_Milošević 0.7
2 Milošević_(surname) 0.1
3 Boki_Milošević 0.1
4 Alexander_Milošević 0.05
…
Local and global statistical features
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Wikification Pipeline 4 – Determine NILs
...ousted long time Yugoslav President Slobodan Milošević in October. Mr. Milošević's Socialist Party…
k ek4 sk
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1 Socialist_Party_(France) 0.23
k ek3 sk
3
1 Slobodan_Milošević 0.7
Is the top candidate really what the text referred to?
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Talk Outline
Why Wikification? Introduction
Motivation Approach
Wikification Pipeline Formulation Relational Analysis
Evaluation Result Entity Linking
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Formulation (0)
Intuition Promote pairs of concepts coherent with textual relations
Mubarak, the wife of deposed Egyptian President Hosni Mubarak, …
(Mubarak, wife, Hosni Mubarak)
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Formulate as an Integer Linear Program (ILP):
If no relation exists, collapse to the non-structured decision
Formulation (1)
Whether a relation exists between and
weight of a relation
Whether to output th candidate of the th mentionweight to output
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Formulation (2)
...ousted long time Yugoslav President Slobodan Milošević in October. Mr. Milošević's Socialist Party…
k ek4 sk
4
1 Socialist_Party_(France) 0.23
2 Socialist_Party_(Portugal) 0.16
3 Socialist_Party_of_America 0.07
4 Socialist_Party_(Argentina) 0.06
…
k ek3 sk
3
1 Slobodan_Milošević 0.7
2 Milošević_(surname) 0.1
3 Boki_Milošević 0.1
4 Alexander_Milošević 0.05
…
r(1,2)34
eki: whether a concept is chosen
ski : score of a concept
r(k,l)ij: whether a relation is present
w(k,l)ij : score of a relation
r(4,3)34
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Overall Approach
Wikification
Candidate
Generation
Relation Analysis
Relation Identification
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Relation Identification
ACE style in-document coreference Extract named entity-only coreference relations with high precision
Syntactico-Semantic relations (Chan & Roth ‘10)
Easy to extract with high precision Aim for high recall, as false-positives will be verified and discarded Sparse, but covers ~80% relation instances in ACE2004
Type Example
Premodifier Iranian Ministry of Defense
Possessive NYC’s stock exchange
Formulaic Chicago, Illinois
Preposition President of the US
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Relation Identification
...ousted long time Yugoslav President Slobodan Milošević in October. Mr. Milošević's Socialist Party…
Argument 1 Relation Type Argument 2
Yugoslav President apposition Slobodan Milošević
Slobodan Milošević coreference Milošević
Milošević possessive Socialist Party
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Overall Approach
Wikification
Candidate
Generation
Relation Analysis
Relation Identification
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Relation Retrieval
Current approach Collect known mappings from Wikipedia page titles, hyperlinks… Limit to top-K candidates based on frequency of links (Ratinov et al.
2011) What concepts can “Socialist Party” refer to?
...ousted long time Yugoslav President Slobodan Milošević in October. Mr. Milošević's Socialist Party…
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Uninformative Mentions
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Relation Retrieval
What concepts can “Socialist Party” refer to? More robust candidate generation
Identified relations are verified against a knowledge base (DBPedia) Retrieve relation arguments matching “(Milošević ,?,Socialist Party)”
as our new candidates
...ousted long time Yugoslav President Slobodan Milošević in October. Mr. Milošević's Socialist Party…
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Query Pruning Only 2 queries per pair necessary due to strong baseline.
Relation Retrieval
q1=(Socialist Party of France,?, *Milošević*)q2=(Slobodan Milošević,?,*Socialist Party*)
k ek4 sk
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1 Socialist_Party_(France) 0.23
…
k ek3 sk
3
1 Slobodan_Milošević 0.7
…
...ousted long time Yugoslav President Slobodan Milošević in October. Mr. Milošević's Socialist Party…
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Relation Retrieval
Argument 1 Relation Type Argument 2
Milošević possessive Socialist Party
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Relation Retrieval
...ousted long time Yugoslav President Slobodan Milošević in October. Mr. Milošević's Socialist Party…
k ek4 sk
4
1 Socialist_Party_(France) 0.23
2 Socialist_Party_(Portugal) 0.16
3 Socialist_Party_of_America 0.07
4 Socialist_Party_(Argentina) 0.06
…
21 Socialist_Party_of_Serbia 0.0
k ek3 sk
3
1 Slobodan_Milošević 0.7
2 Milošević_(surname) 0.1
3 Boki_Milošević 0.1
4 Alexander_Milošević 0.05
…
𝑟34(1,21)=1
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Overall Approach
Wikification
Candidate
Generation
Relation Analysis
Relation Identification
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Relational Inference
...ousted long time Yugoslav President Slobodan Milošević in October. Mr. Milošević's Socialist Party…
k ek4 sk
4
1 Socialist_Party_(France) 0.23
2 Socialist_Party_(Portugal) 0.16
3 Socialist_Party_of_America 0.07
4 Socialist_Party_(Argentina) 0.06
…
21 Socialist_Party_of_Serbia 0.0
k ek3 sk
3
1 Slobodan_Milošević 0.7
2 Milošević_(surname) 0.1
3 Boki_Milošević 0.1
4 Alexander_Milošević 0.05
…
𝑟34(1,21)=1
𝑤34(1,21)=?
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Relation scoring
Query scoring as a tie-breaker between multiple relations Explicit relations are stronger than a hyperlink relations Normalize score for each pair of mention to
𝑤=1𝑍 𝑓 (𝑞 ,𝜎 )
Retrieved relation tupleRelation query
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Relational Inference
...ousted long time Yugoslav President Slobodan Milošević in October. Mr. Milošević's Socialist Party…
k ek4 sk
4
1 Socialist_Party_(France) 0.23
2 Socialist_Party_(Portugal) 0.16
3 Socialist_Party_of_America 0.07
4 Socialist_Party_(Argentina) 0.06
…
21 Socialist_Party_of_Serbia 0.0
k ek3 sk
3
1 Slobodan_Milošević 0.7
2 Milošević_(surname) 0.1
3 Boki_Milošević 0.1
4 Alexander_Milošević 0.05
…
𝑟34(1,21)=1
1
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Relational Inference - coreference
...ousted long time Yugoslav President Slobodan Milošević in October. Mr. Milošević's Socialist Party…
k ek2 sk
2
1 Slobodan_Milošević 1.0
k ek3 sk
3
1 Slobodan_Milošević 0.7
2 Milošević_(surname) 0.1
3 Boki_Milošević 0.1
4 Alexander_Milošević 0.05
…
𝑟23(1,1)=1
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Overall Approach
Wikification
Candidate
Generation
Relation Analysis
Relation Identification
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Determine unknown concepts (NILs)
How to capture the fact: “Dorothy Byrne” does not refer to any concept in Wikipedia
Identify coreferent nominal mention relations Generate better features for NIL classifier
Dorothy Byrne, a state coordinator for the Florida Green Party,…
k ek2 sk
2
1 Green_Party_of_Florida 1.0
k ek1 sk
1
1 Dorothy_Byrne_(British_Journalist)
0.6
2 Dorothy_Byrne_(mezzo-soprano)
0.4
nominal mention
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Determine unknown concepts (NILs)
Create NIL candidate for propagation
Dorothy Byrne, a state coordinator for the Florida Green Party,…
k ek2 sk
2
1 Green_Party_of_Florida 1.0
k ek1 sk
1
0 NIL 1.0
1 Dorothy_Byrne_(British_Journalist)
0.6
2 Dorothy_Byrne_(mezzo-soprano)
0.4
nominal mention
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Talk Outline
Why Wikification? Introduction
Motivation Approach
Wikification Pipeline Formulation Relational Analysis
Evaluation Result Entity Linking
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Wikification Performance Result
ACE MSNBC AQUAINT Wikipedia60
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F1 Performance on Wikification datasets
Milne&WittenRatinov&RothRelational Inference
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Evaluation – TAC KBP Entity Linking
Wikipedia Articles
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500000
1000000
1500000
2000000
2500000
3000000
3500000
4000000
4500000
5000000
TAC KBNon-TAC KB
Task Definition Links a named entity in a document to
either a TAC Knowledge Base (TAC KB) node or NIL
Cluster NIL entities Relevant Tasks
Wikification Cross-document coreference
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Evaluation – TAC KBP Entity Linking
Run Relational Inference (RI) Wikifier “as-is”: No retraining using TAC data
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RI
CogComp
LCC
MS_MLI
NUShim
e
*Median
TAC KBP 2011 Entity Linking Performance
Micro AverageB³F1
System Names*Median of top 14 systems
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Conclusion
Importance of linguistic and world knowledge Identification of relational information benefits Wikification Introduced an inference framework to leverage better
language understandings Future work
Accumulate what we know about NIL concepts Joint entity typing, coreference and disambiguation Incorporate more relations
*Demo will be updated in a week at: http://cogcomp.cs.illinois.edu/demo/wikify Download at: http://cogcomp.cs.illinois.edu/page/download_view/Wikifier
Thank you!
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BACK UP SLIDESBack up slides
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Massive Textual Information
How can we know more from large volumes of possibly unfamiliar raw texts?
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Massive Textual Information
We naturally “look up” concepts and accumulate knowledge.
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Challenges
It’s a version of Chicago – the standard classic Macintosh menu font…
Tuesday marks the 142nd anniversary of an event that forever altered the course of Chicago's development as a then-young American city
By the time the New Orleans Saints kicked off at Soldier Field on Sunday afternoon, their woeful history in the Windy City was fully understood.
?
Ambiguity
Variety
Concepts outside of Wikipedia (NIL)
Challenges
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It’s a version of Chicago – the standard classic Macintosh menu font…
Tuesday marks the 142nd anniversary of an event that forever altered the course of Chicago's development as a then-young American city
By the time the New Orleans Saints kicked off at Soldier Field on Sunday afternoon, their woeful history in the Windy City was fully understood.
?Chicago Chicago
Chicago font
ChicagoChicago
The Windy City
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Organizing knowledge
Wikipedia as a source of “common sense” knowledge Naturally bridges rich structured knowledge and text data Comprehensive for most purposes
~4.3 million English articles as of today Cross-lingual
Estimated size of a printed version of Wikipedia as of August 2010. *Picture courtesy of Wikipedia
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Motivating Example
Relatively sparse, but act as hard constraints
Intuitively, we need to “de-coreference” this pair of mention Opens a new dimension in text understanding
helps all stages of Wikification
Mubarak, the wife of deposed Egyptian President Hosni Mubarak, …
Mubarak
Hosni Mubarak
Egyptian President
wife
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Wikification Approach
Mention Segmentation Use Shallow Parsing, NER and regular expression to generate likely
mentions of concepts. Match nested mentions using dictionary. Discard unknown mentions.
...ousted long time Yugoslav President Slobodan Milošević in October. Mr. Milošević's Socialist Party…
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Ranking
Features Local features from Bag of Words (BOW) representation, such as
various TFIDF windows. Global features from Bag of Concepts (BOC) representation.
What are we losing?
Mubarak
Hosni Mubarak
Egyptian President
wife
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Relation Extraction
In document coreference Extract entity-only coreference relations with high precision
Syntactico-Semantic relations (Chan & Roth ‘10)
Easy to extract with high precision Deep parsing too slow
Premodifier Iranian Ministry of Defense
Possessive NYC’s stock exchange
Formulaic Chicago, Illinois
Preposition President of the US
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Relational Inference
...ousted long time Yugoslav President Slobodan Milošević in October. Mr. Milošević's Socialist Party
Coreference
Possessive
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Relational Inference
...ousted long time Yugoslav President Slobodan Milošević in October. Mr. Milošević's Socialist Party
How to look up knowledge and use these relations?
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Wikification Approach
Recall concepts Rank concepts Determine unknown concepts (NILs)
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Determine NILs
Dorothy Bryne, a state coordinator for the Florida Green Party
Leverage nominal mention relations to construct limited context
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Relational Inference Example
...like Chicago O'Hare and [La Guardia] in [New York],...
Wikipedia Page Ski
LaGuardia_Airport 0.36La_Guardia 0.22Fiorello_La_Guardia 0.18La_Guardia,_Spain 0.11
Wikipedia Page Ski
New_York 0.53New_York_City 0.44New_York_(magazine) 0.01New_York_Knicks 0.01
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Relational Inference Scenario 1
...like Chicago O'Hare and [La Guardia] in [New York],...
Wikipedia Page ScoreLaGuardia_Airport 0.36La_Guardia 0.22Fiorello_La_Guardia 0.18La_Guardia,_Spain 0.11
Wikipedia Page ScoreNew_York 0.53New_York_City 0.44New_York_(magazine) 0.01New_York_Knicks 0.01
Γ = 0.18+0.53 = 0.71
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Relational Inference Scenario 2
...like Chicago O'Hare and [La Guardia] in [New York],...
Wikipedia Page ScoreLaGuardia_Airport 0.36La_Guardia 0.22Fiorello_La_Guardia 0.18La_Guardia,_Spain 0.11
Wikipedia Page ScoreNew_York 0.53New_York_City 0.44New_York_(magazine) 0.01New_York_Knicks 0.01
Γ = 0.36+0.44 = 0.8
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Relational Inference Conclusion
...like Chicago O'Hare and [La Guardia] in [New York],...
Pr(Γ= ) > Pr(Γ= )
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Constraint scaling
Lexical similarity as a tie-breaker between multiple relations Explicit relations are stronger than a hyperlink relations Normalize score for each pair of mention to [0,1]
Relation scaling factor
Query lexical similarityNormalization factor
: query: a retrieved relation triple
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Wikification Pipeline 1 - Mention Segmentation
...ousted long time Yugoslav President Slobodan Milošević in October. Mr. Milošević's Socialist Party…
Sub noun phrase chunks and NER segments (Ratinov et al. 2011)
Regular expression capturing longer composite mentions President of the United States of America