Introducing CRL Computing Research Laboratory. The Computing Research Laboratory at NMSU Jim Cowie...
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Transcript of Introducing CRL Computing Research Laboratory. The Computing Research Laboratory at NMSU Jim Cowie...
Introducing CRL
Computing
Research
Laboratory
The Computing Research Laboratory at NMSUJim Cowie – Director
Steve Helmreich – Deputy Director / [email protected] http://crl.nmsu.edu
• Established in 1983 by New Mexico Legislature as a Center of Technical Excellence
• CRL is a Research Department in the College of Arts and Sciences at New Mexico State University
• From 1983 to 1989 received more than $6.5 million in state funding.
• Since 1990, entirely self-supporting on research grants and contracts.
C R LC O M P U T IN G
R E S E A R C HL A B O R A T O R Y
CRL Capabilities and Expertise
• Multi-lingual text processing• Speech processing and generation• Human Computer Interaction• Team of Computer Scientists, Psychologists,
Linguists, Computational Linguists, Geographers, Biochemists and Mathematicians; (~40)
• capable of delivering complex, working, prototype systems.
C R LC O M P U T IN G
R E S E A R C HL A B O R A T O R Y
Information retrievalLanguage learning and language
teachingAutomatic translationSummarizationQuestion answeringDictionary developmentKnowledge discovery
Language Engineering at CRL
Overview of Talk
• Projects related to Machine Translation– Pragmatics-based Machine Translation– Jargon analysis project– IL Annotation project
• Projects using Machine Translation– Expedition / Boas– MOQA (Question / Answering)
Machine Translation triangle
Source Language
Target Language
Direct Translation
Transfer
Interlingual (IL)
Analysis Generation
Machine Translation triangle
Source & Target Language
Target & Source Language Direct Translation
Transfer
Interlingual (IL)
Analysis & Generation
Generation & Analysis
Machine Translation triangle
Source & Target Language
Target & Source Language Direct Translation
Transfer
Interlingual (IL)
Analysis & Generation
Generation & Analysis
CRL Machine Translation Projects
• XTRA – Chinese-English IL, 1986-88
• ULTRA – five languages IL, 1988-90
• Pangloss – multi-site Spanish-English IL, 1992-95
• Mikrokosmos – Spanish-English IL, 1995-98
• Corelli – multi-lingual transfer, 1998-2001
Characteristics of IL MT
• Analysis to and generation from “meaning” of the input
• Disambiguation to an unambiguous language-independent representation (IL)
• Use of world knowledge to disambiguate
• World knowledge stored and manipulated through an Ontology
Jesus of Montreal
• Woman to priest guiltily coming out of her bedroom (in French): “Come on out, we’re not playing a scene from Feydeau.”
• English subtitle: “Come on out. This isn’t a bedroom farce.”
Which floor is this?
• In a Spanish newspaper article about expensive real estate rental in Moscow:
“Nothing’s available on the “segundo piso” but there’s still some space left
on the “tercero piso.”
• T1: second floor / third floor
• T2: third floor / fourth floor
Earthquakes – who is to blame?
• Acumulación de víveres por anuncios sísmicos en Chile
• Hoarding Caused by Earthquake Predictions in Chile
• STOCKPILING OF PROVISIONS BECAUSE OF PREDICTED EARTHQUAKES IN CHILE
Pragmatics-based MT hypothesis
• Translations are made on the basis of interpretations
• Interpretations are a set of coherent inferences about the content and the context of the message
• These inferences are based on – Beliefs of the translator about the beliefs of the author
– Beliefs of the translator about the beliefs of the target audience
– Beliefs of the translator about the world
Machine Translation triangle
Source & Target Language
Target & Source Language Direct Translation
Transfer
Interlingual (IL)
Analysis & Generation
Generation & Analysis
Interpretations
Terrorist/Freedom Fighter
• sindicalistas: Union Members / Labor Leaders
• asesino: killer / assassin
• asesinados: murdered / assassinated
• campesinos: small farmers / peasants
• sin tierras: without land / landless
• terrateniente: landowner / landholder
Hypothesis
• It is possible to identify an author's viewpoint from the vocabulary (jargon) used, particularly in the use of alternate lexical items referring to the same concept or object
Hypothesis
• Social groups are organized not just around topics but also around points of view and
• develop jargons to express those points of view • Members of those social groups generally hold to
those points of view and• Use the jargons to express themselves• THUS identifying an author’s jargon also
identifies the groups he/she belongs to and the beliefs he/she is likely to hold
Training Corpus
• Issue: Abortion
• Text Size: approximately 8000 tokens each
• Text Size (types): 2273 pro-choice / 2168 pro-life
• Significant unique vocabulary: 79 pro-choice / 68 pro-life
• Significant common vocabulary 113 / 37
Approach
• Unique vocabulary: 1581 pro-choice/1476 pro-life
• Common vocabulary: 692
• Significant unique vocabulary:– 79 pro-choice– 68 pro-life
• Significant common vocabulary: 113 (37)
Unique Vocabulary – Pro-life
• abnormalities, aborted, abortifacient, abortifacients, abortion-inducing, abortionist, abortionists, adultery, amniotic, bible, blessed, cancer-causing, chastisement, chastisements, chastises, complication, complications, contrite, creator, depression
Unique Vocabulary – Pro-choice
• activism, activists, alley, anti-abortion, anti-choice, anti-democratic, antiabortionists, arson, arsonist, arsons, attorney, attorney’s, blockade, blockaders, blocked, blocking, bomb, bombing, bombings
Significant Common Vocabulary
• Pro-life• clinic(s) 3• fetus 22• parenthood 2• planned 2• unborn 15• week(s) 37• woman(‘s) 9
• Pro-choice• unborn 1• clinic(s) 46• fetus 7• parenthood 14• planned 15• week(s) 8• woman(‘s) 27
One-year project
• Using sounder statistical measurements– Base line corpus– Statistically significant differences– Other methods of measuring differences
• Using collocations as well as single words• Looking for “synonymous” terms
– WordNet– Ontology– Rogets
Experiments
• Differentiate opinions in a binary opposition within texts on the subject of opposition
• Differentiate opinions among a plurality of views within texts on the subject
• Differentiate opinions in a binary opposition within texts on a different subject
• Differentiate opinions among a plurality of views within texts on a different subject
• Differentiate multiple viewpoints in any article
Problems with IL approach
• Idiosyncratic – no common understanding of what IL should be or look like
• Limited automatic acquisition – most of the knowledge-based and lexicon is hand-coded
Interlingual Annotation of Multilingual Text Corpora
Computing Research Laboratory – NMSUMitre Corporation
UMIACS – U MarylandColumbia University
Language Technologies Institute – CMUInformation Sciences Institute – USC
Approach
• Collection of texts in six languages
• Three translations of each into English
• Tools to analyze grammatical aspects– Morphological analysis– Name recognition– Chunking
Develop IL Representation
• Through study of texts
• Through examination of current Ils
• Develop formal definition– Rich representation– Compatible with under-specification
• Develop coding manuals and guarantee inter-coder reliability
Annotate the Corpus
• All sites / all texts
• One site in charge of one aspect of IL
• Frequent interaction
• Regular joint meetings
Evaluate the results
• Inter-coder reliability
• Growth rate
• Grain size
• Quality of generation
Trends in HLT Research Funding
• Focus on sub-tasks– Named entity recognition– Coreference resolution– Word sense disambiguation
• Bring multi-lingual capabilities to parallel technologies– Multi-lingual IR/IE/summarization
• Bring multiple technologies into one project
Three such projects at CRL
• Expedition / Boas
• MOQA – Meaning-Oriented Question/Answering
• Personal Profiler
Expedition: A tool for building Machine Translation systems
The ProblemGiven two people, a linguist who knows a language,
and a programmer, provide a support system which allows them to build a machine translation system for that language in six months.
Project is completed and we are now using it to build translation systems for Somali and Urdu.
You can try out the system at http://aiaia.nmsu.edu
Boas: “A Linguist in the Box”
Boas is a semi-automatic knowledge elicitation system that guides a language speaker through the process of developing the static knowledge sources for a moderate-quality, broad-coverage MT system from any “low-density” language into English in about six months.
Some of the tasks include providing a list of characters and morphological features, paradigms for inflected classes, equivalents of closed-class items, translation of place names and open class items from English into the source language.
LLanguage knowledge acquisition has been a bottleneck for MT development and deployment for over 40 years. At the same time, the dearth of data resources has strongly limited the deployment of any of the recent corpus-based techniques in practical MT environments.
Expedition is a “quick ramp-up” MT environment between “low density” languages and English which is a step to alleviating these problems.
Boas, the main knowledge acquisition module inside Expedition, includes resident knowledge about
•a set of potential source languages
•generalized parametric typological knowledge about languages in general and
•methods and configurations for human-computer interaction.
It is designed for use by a team which does not include trained computational linguists.
Boas contains knowledge about human language and means of realization of its phenomena in a number of specific languages and is, thus, a kind of a “linguist in the box” that helps non-professional acquirers with the task whose complexity is well-known.
The ethnologist and linguist Franz Boas was the founder of the American school of descriptive linguistics.
In this photo, circa 1900?, he is shown posing for a model which was being made of a Kwakuitl Winter Ceremonial dancer in which the dancer emerges from within a circular hole cut in the dancing screen.
Meaning-Oriented Question-Answering with Ontological Semantics
An AQUAINT Project from
ILIT
Development Strategy
• Meaning oriented question answering• Rapid Prototyping using pre-existing components• Evaluation of end-to-end system performance for
specific tasks (collaboration with AWARE project, Bill Ogden, CRL)
• Project commenced August 2002• Current system runs on Linux or Windows 2000
Meaning-Oriented Question-Answering with Ontological Semantics
• Initial Domain: travel and meetings– question understanding and interpretation– determining the answer and
– presenting the answer
• two kinds of data source
– Structured Fact Repository containing instances of ontological entities
– open text (in English, Arabic and Farsi)
System Overview (V0)
Fact Repository
TextAnalyzer
Query Interface
& Answer
Formulation
DocumentSources
HumanAcquisition
humanmachine
Document Retrieval
System Overview (V1 now)
Document Retrieval
Fact Repository
TextAnalyzer
Query Interface
& Answer
Formulation
DocumentSources
human
batchreal-time
questions
System Overview (V2)
Document Retrieval
Fact Repository
TextAnalyzer
Query Interface
& Answer
Formulation
DocumentSources
human
batchreal-time
questions& texts
Batch Processing Overview
Web Spider
Keizai Indexing
Documents
DocumentCollection
Keizai Retrieval DocumentSubset
Text Analysis Text MeaningRepresentation
TMR to FRConverter Fact Repository
Batch Mode - Fact Repository Population
• Spidered contemporary text• Retrieval done using Keizai retrieval
system (Unicode based)• Uses a list of interesting people and
travel keywords• Selected documents saved and
automatically processed using UMBC’s analyzer (which produces text meaning representations)
• Instances of concepts from TMR extracted and stored in Fact Repository
Interactive Processing Overview
Query Interface
Information Server
NLQuery
Analyzer
TMR
Instances
Instance Finder
Fact Repository
XML Answer
Answer formulation
Interactive Mode – Question Answering
Question submitted – text or structured queryRouted to Fact Repository (Structured Queries)
orTo Text Analyzer (NL queries)Question converted to TMRTMR to:
• Structured query (if good match and sent to user for validation), or
• Converted to a direct Fact Repository query
Answer retrieved from FR and displayed• Fall back queries if basic query cannot be
answered
Follow up queries can be further questions or use the multi-modal facilities of the interface.
A trace of the dialog is maintained.
Information Server • Mediates between User Interface and all
System Components• Fact Repository• Question Analysis• TMR Production
• Uses XML to communicate with Answer Formulation Component
• Java structures communicate with fact repository interface
• Java-lisp interface communicates with text analyzer
Structured Fact Repository
• Uniform format for all kinds of data
• Uniform support for multiple applications and tools
• Semantically anchored in general ontology
• Implemented using PostgreSQL
(REQUEST-INFO-842
(THEME (VALUE (MEMBER-OF-842.DOMAIN)))
(INSTANCE-OF (VALUE (REQUEST-INFO)))
)
(MEMBER-OF-842
(TIME (VALUE ((FIND-ANCHOR-TIME))))
(RANGE (VALUE (POLITICAL-ENTITY-842)))
(INSTANCE-OF (VALUE (MEMBER-OF)))
)
(POLITICAL-ENTITY-842
(OBJECT-NAME (VALUE ("Al Qaeda")))
(INSTANCE-OF (VALUE (POLITICAL-ENTITY)))
)
TMR for “Who is in al Qaeda?”
try-v3syn-struc
root trycat vsubj root $var1
cat nxcomp root $var2
cat vform OR infinitive gerund
sem-strucset-1 element-type refsem-1
cardinality >=1refsem-1 sem event
agent ^$var1effect refsem-2
modalitymodality-type epiteucticmodality-scope refsem-2modality-value < 1
refsem-2 value ^$var2sem event
REQUEST-INFO-130 THEME DEVELOP-2601.PURPOSE DEVELOP-2601.REASON TEXT-POINTER why INSTANCE-OF REQUEST-INFO
DEVELOP-2601THEME SET-2555AGENT NATION-97PHASE CONTINUOUS
TIME FIND-ANCHOR-TIME INSTANCE-OF DEVELOP
TEXT-POINTER developing
NATION-97HAS-NAME Iraq
INSTANCE-OF NATIONTEXT-POINTER Iraq
SET-2555 ELEMENT-TYPE WEAPONCARDINALITY > 1
INSTRUMENT-OF KILL-1864 THEME-OF DEVELOP-2601 INSTANCE-OF WEAPON
TEXT-POINTER weapons
KILL-1864 THEME SET-2556 INSTRUMENT SET-2555 INSTANCE-OF KILL
TEXT-POINTER destruction
SET-2556 THEME-OF KILL-1225 ELEMENT-TYPE HUMAN
CARDINALITY > 100 INSTANCE-OF HUMAN
TEXT-POINTER mass
“Why is Iraq developing weapons of mass destruction?”
Resume GeneratorGenerating a resume for an individual:1. Collect and prepare the data
Gather documents from the web in English, Russian and Spanish.Filter the documents to reduce the data to a collection of related documents.
2. Individual Document Summarization (This is done for each document in the collection)Determine a date for the documentSelect concise relevant pieces of information from the filtered collection of
documents.Determine a date for each of the selected extracts.Translate the pieces of text into English (our target language).
3. Profile GenerationMerge the translated text extracts in chronological order to produce the cross
document summary.Generate the output form for the end user.
Language Engineers in Short Supply
• Emerging field – combining Linguistics, Computational Linguistics, Computer Science, Systems Analysis, and Human Factors
• Masters Degrees being offered at – – University of Southern California– Arizona University– University of Colorado– Carnegie Mellon University
• Potential for both for supporting research and developing applications.
Former CRL Staff and Students are working on language applications at -
• Microsoft Natural Language Group• Systran• AT&T• Telelogue (talking yellow pages)• Westlaw (Spanish language processing group)• General Electric• Motorola Chinese Telephony Group• The Institute for Genetic Research (TIGR) (bio-
informatics)• University of Maryland Baltimore County• University of Sheffield
Appendix
Ecology Development
Challenges and Needs• Research into appropriate processing methods for
language ecology is needed. Only a tiny handful of languages have had any kind of research/evaluation effort for these topics (English, French, Japanese, Spanish).
• Research corpora need to be produced and made publically available. Main source of materials at the the moment is the Linguistic Data Consortium
• (http://www.ldc.upenn.edu/ )• Language processing resources such as proper
name lists (onomastica), lexicons, morphological analyzers, and patterns of features for names need to be produced
Requirements for Basic Analysis
• Corpora
• Markup
• Character sets
• Punctuation
• Part of Speech Tagging
• Noun Phrase Recognition
Requirements (Continued)
• Numbers and Dates
• Onomastica
• Un-attributed Proper Names
• Syntax
• General Guidelines
• Challenges and Problems
Why do We Need Corpora?
• Ground our development in reality
• Provide basis for statistical processing– testing– learning
Types of Corpus
• Raw - only markup from the source - e.g. newswire
• Cleaned - standardized markup - e.g. TREC corpora
• NLP specific markup - e.g. Penn treebank, Wall Street Journal
• Parallel Corpora with alignment markup
Sources - Standard
• Linguistic Data Consortium - LDC
• European Language Resources Agency - ELRA
• National Institute for Standards and Technology - NIST
• Gutenberg Archive
• Oxford Text Archive
• International Computer Archive for Modern English - ICAME
• + Many national initiatives
Sources - Do It Yourself
• Participation in evaluations– TREC, MUC, Amaryllis, Semeval
benefits are tagged corpora focused on a specific task
• Web spidering– Site grabbing – web spiders
– Language grabbing - CRL language recognizing web spider
• Newswire capture
• Parallel Corpora – Embassies, Company web sites
– United Nations, Pan American Health Organization
Character Sets• For 8 bit
– Various ISO standards – Latin 1 – Latin 5– Microsoft variants– Others – e.g. KOI8 for Russian
• Various 16 bit Japanese and Chinese standards – EUC, SJIS, Big5….
• Unicode– UTF8 – mixed 8 and 16 bit– UCS2 – 16 bit (although many characters can
be composed of multiple characters)
Character Sets
• Eight bit character sets may be simpler if processing only one language, or one language + English
• Unicode offers the possibility of universal tokenization (recognizing words), based on character classifications
• Key is to make sure resources and data being processed use the same character set
Sentence Segmentation
• Essential step in analysis• Complicated by ambiguous use of punctuation and
by document headings and sub-headings (which should be processed separately)
• For language with “.” used as an abbreviation marker needs list of abbreviations + automatic recognition of abbreviations using lexicon
• Still requires heuristics to handle abbreviations at the end of a sentence.
Part of Speech Tagging
• Either statistical based on tagged corpora or rule based. Tags here are based Penn treebank
(‘november’,’NP’) ( ‘24’,’CD’) ( ‘,’,’,’) ( ‘1989’,’CD’) (‘,’,’,’) (‘friday’,’NP’) (‘bridgestone’,’NP’) (‘sports’,’NPS’) (‘co’,’NP’) (‘said’,’VBD’) (‘friday’,’NP’) (‘it’,’PP’) (‘has’,’VBZ’) (‘set’,’VBN’) (‘up’,’RP’) (‘a’,’DT’) (‘joint’,’JJ’) (‘venture’,’NN’) (‘in’,’IN’)
Phrase Recognition
• Goal is to reduce the complexity of text processed by Semantic Analysis to processing heads of phrases
• To recognize, for example, noun phrases describing companies -– “the third Japanese electric appliance concern”
– “the new company”
• and to recognize noun phrases in general– “golf clubs”, “metal woods”
Morphological Analysis
• Inflection analysis + part of speech tagging
• Needed to detect various features– Number, tense, gender, role …..
• And to produce a citation form for lexical lookup
• MORE?
Numbers and Dates• Numbers in numeric and alphabetic form can be
recognized and grouped with punctuation and qualifiers using simple regular expressions– Percentages, money, temperatures, weights etc.
• Dates can also be recognized by regular expressions by adding months and a few separator characters to the set of tokens used by the regular expressions– Thus NUM SLASH NUM SLASH NUM would be an
acceptable date expression, tests on ranges could be added
• Many languages support multiple calendars and these all need to be supported (Japanese, Arabic)
Onomastica
• Lists of proper names are an essential resource for text processing.
• Do not need to be huge as many can be recognized automatically using context patterns – e.g. “we enjoyed our visit to Plaster, Texas”
• A large list of place names + well known people and company names that can be regularly found in abbreviated form (Ford, Bush etc.)
• Transliteration software may be useful to help understanding in translated texts
Un-attributed Proper Names
For each language the following resources are required
• databases of proper name components
– Human names, company terminators, company start and end words, all the contents of the Onomasticon
• patterns to combine proper name components
– Mostly regular expressions
• name abbreviation algorithms
Toyota Motor Corporation -> Toyota Motor -> Toyota
International Business Machines -> IBM
• context based patterns
– A spokesman for eBay said ….
Syntax
• Simple syntax probably sufficient before semantic (user oriented) steps– Noun phrases– Compound verbs– Subordinate clauses
General Guidelines
• The main guideline is to preserve a “reasonable” amount of ambiguity for resolution by the semantic analysis process– Toyota – might be a product or a company
– Washington – might be a place or a person
– Taj Mahal – might be a mausoleum, or a casino
• But definite decisions should be made where possible to reduce the load on the analyzer