Text Mining: Finding Nuggets in Mountains of Textual Data
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Transcript Text Mining: Finding Nuggets in Mountains of Textual Data
Text Mining: Finding Nuggets in
Mountains of Textual Data
Jochen Dijrre, Peter Gerstl, Roland Seiffert
Presented by Ebrahim Kobeissi
Text in this color are my additions/modifications
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Outline
Motivation
Methodology
Feature Extraction
Clustering and Categorizing
Some Applications
Comparison with Data Mining
Conclusion & Exam Questions
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Motivation
A large portion of a company’s data is
unstructured or semi-structured
Letters
Emails
Phone transcripts
Contracts
Technical documents
Patents
Web pages
Articles
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Definition
Text Mining:
the discovery by computer of new, previously
unknown information, by automatically
extracting information from different written
resources
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Typical Applications
Summarizing documents
Discovering/monitoring relations among people,
places, organizations, etc
Customer profile analysis
Trend analysis
Documents summarization
Spam Identification
Public health early warning
Event tracks
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Outline
Motivation
Methodology
Comparison with Data Mining
Feature Extraction
Clustering and Categorizing
Some Applications
Conclusion & Exam Questions
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Methodology: Challenges
Information is in unstructured textual form
Natural language interpretation is difficult &
complex task! (not fully possible)
Watson is a step closer
Text mining deals with huge collections of
documents
Impossible for human examination
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Methodology: Two Aspects
Knowledge Discovery
Extraction of codified information
Feature Extraction
Mining proper; determining some structure
Information Distillation
Analysis of feature distribution
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Two Text Mining Approaches
Extraction
Extraction of codified information from single
document
Analysis
Analysis of the features to detect patterns, trends,
etc, over whole collections of documents
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Outline
Motivation
Methodology
Feature Extraction
Clustering and Categorizing
Some Applications
Comparison with Data Mining
Conclusion & Exam Questions
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IBM Intelligent Miner for Text
IBM introduced Intelligent Miner for Text in 1998
SDK with: Feature extraction, clustering,
categorization, and more
Not a drop in application
Traditional components (search engine, etc)
The rest of the paper describes text mining
methodology of Intelligent Miner.
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Feature Extraction
Recognize and classify “significant”
vocabulary items from the text
Categories of vocabulary
Proper names – Mrs. Albright or Dheli[sic], India
Multiword terms – Joint venture, online document
Abbreviations – CPU, CEO
Relations – Jack Smith-age-42
Other useful things: numerical forms of numbers,
percentages, money, etc
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Canonical Form Examples
Normalize numbers, money
Four = 4, five-hundred dollar = $500
Conversion of date to normal form
Morphological variants
Drive, drove, driven = drive
Proper names and other forms
Mr. Johnson, Bob Johnson, The author = Bob
Johnson
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Feature Extraction Approach
Linguistically motivated heuristics
Pattern matching
Limited lexical information (part-of-speech)
Avoid analyzing with too much depth
Does not use too much lexical information
No in-depth syntactic or semantic analysis
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Advantages to IBM’s approach
Processing is very fast (helps when dealing
with huge amounts of data)
Heuristics work reasonably well
Generally applicable to any domain
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Outline
Motivation
Methodology
Comparison with Data Mining
Feature Extraction
Clustering and Categorizing
Some Applications
Conclusion & Exam Questions
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Clustering
Fully automatic process
Documents are grouped according to
similarity of their feature vectors
Each cluster is labeled by a listing of the
common terms/keywords
Good for getting an overview of a document
collection
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Two Clustering Engines
Hierarchical clustering
Orders the clusters into a tree reflecting various
levels of similarity
Binary relational clustering
Flat clustering
Relationships of different strengths between
clusters, reflecting similarity
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Clustering Model
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Categorization
Assigns documents to preexisting categories
Classes of documents are defined by providing a set
of sample documents.
Training phase produces “categorization schema”
Documents can be assigned to more than one
category
If confidence is low, document is set aside for
human intervention
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Categorization Model
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Outline
Motivation
Methodology
Feature Extraction
Clustering and Categorizing
Some Applications
Comparison with Data Mining
Conclusion & Exam Questions
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Applications
Customer Relationship Management
application provided by IBM Intelligent
Miner for Text called “Customer
Relationship Intelligence”
“Help companies better understand what their
customers want and what they think about the
company itself”
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Customer Intelligence Process
Take as input body of communications with
customer
Cluster the documents to identify issues
Characterize the clusters to identify the
conditions for problems
Assign new messages to appropriate clusters
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Customer Intelligence Usage
Knowledge Discovery
Clustering used to create a structure that can be
interpreted
Information Distillation
Refinement and extension of clustering results
Interpreting the results
Tuning of the clustering process
Selecting meaningful clusters
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Outline
Motivation
Methodology
Feature Extraction
Clustering and Categorizing
Some Applications
Comparison with Data Mining
Conclusion & Exam Questions
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Comparison with Data Mining
Data mining
Discover hidden
models.
tries to generalize all
of the data into a
single model.
marketing, medicine,
health care
Text mining
Discover hidden
facts.
tries to understand
the details, cross
reference between
individual instances
biosciences,
customer profile
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analysis
Conclusion
This paper introduced text mining and how it
differs from data mining proper.
Focused on the tasks of feature extraction
and clustering/categorization
Presented an overview of the tools/methods
of IBM’s Intelligent Miner for Text
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Exam Question #1
What are the two aspects of Text Mining?
Knowledge Discovery: Discovering a common
customer complaint in a large collection of
documents containing customer feedback.
Information Distillation: Filtering future
comments into pre-defined categories
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Exam Question #2
How does the procedure for text mining
differ from the procedure for data mining?
Adds feature extraction phase
Infeasible for humans to select features manually
The feature vectors are, in general, highly
dimensional and sparse
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Exam Question #3
In the Nominator program of IBM’s Intelligent
Miner for Text, an objective of the design is to
enable rapid extraction of names from large
amounts of text. How does this decision affect the
ability of the program to interpret the semantics of
text?
Does not perform in-depth syntactic or semantic analysis
of the text; the results are fast but only heuristic with
regards to actual semantics of the text.
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Questions?
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