Text Mining: Finding Nuggets in Mountains of Textual Data
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Transcript Text Mining: Finding Nuggets in Mountains of Textual Data
Jochen Dijrre, Peter Gerstl, Roland Seiffert
Presented by Trevor Crum
04/23/2014
*Slides modified from Shamil Mustafayev’s 2013 presentation *
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Outline
Definition and Paper Overview
Motivation
Methodology
Feature Extraction
Clustering and Categorizing
Some Applications
Comparison with Data Mining
Conclusion & Exam Questions
2
Definition
Text Mining:
The discovery by computer of new, previously
unknown information, by automatically extracting
information from different unstructured textual
documents.
Also referred to as text data mining, roughly
equivalent to text analytics which refers more
specifically to problems based in a business
settings.
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Paper Overview
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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Outline
Definition and Paper Overview
Motivation
Methodology
Feature Extraction
Clustering and Categorizing
Some Applications
Comparison with Data Mining
Conclusion & Exam Questions
5
Motivation
A large portion of a company’s data is
unstructured or semi-structured – about
90% in 1999!
Letters
Emails
Phone transcripts
Contracts
Technical documents
Patents
Web pages
Articles
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Typical Applications
Summarizing documents
Discovering/monitoring relations among
people, places, organizations, etc
Customer profile analysis
Trend analysis
Document summarization
Spam Identification
Public health early warning
Event tracks
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Outline
Definition and Paper Overview
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)
Google and Watson are a step closer
Text mining deals with huge collections
of documents
Impossible for human examination
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Google vs Watson
Google justifies the
answer by returning
the text documents
where it found the
evidence.
Google finds
documents that are
most suitable to a
given Keyword.
Watson tries to
understand the
semantics behind
a given key phrase
or question.
Then Watson will
use its huge
knowledge base to
find the correct
answer.
Watson uses more AI
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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 a
single document
Analysis
Analysis of the features to detect patterns,
trends, and other similarities over whole
collections of documents
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Outline
Definition and Paper Overview
Motivation
Methodology
Feature Extraction
Clustering and Categorizing
Some Applications
Comparison with Data Mining
Conclusion & Exam Questions
13
Feature Extraction
Recognize and classify “significant”
vocabulary items from the text
Categories of vocabulary
Proper names – Mrs. Albright or Dheli, India
Multiword terms – Joint venture, online document
Abbreviations – CPU, CEO
Relations – Jack Smith-age-42
Other useful things: numerical forms of
numbers, percentages, money, dates, and
many other
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Canonical Form Examples
Normalize numbers, money
Four = 4, five-hundred dollar = $500
Conversion of date to normal form
8/17/1992 = August 18 1992
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-ofspeech)
Avoid analyzing with too much depth
Does not use too much lexical information
No in-depth syntactic or semantic analysis
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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
Traditional components (search engine, etc)
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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
Definition and Paper Overview
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
Definition and Paper Overview
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” or CRI
“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
Definition and Paper Overview
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
analysis
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Outline
Definition and Paper Overview
Motivation
Methodology
Feature Extraction
Clustering and Categorizing
Some Applications
Comparison with Data Mining
Conclusion & Exam Questions
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Conclusion
Text mining can be used as an effective
business tool that supports
Creation of knowledge by preparing and
organizing unstructured textual data
[Knowledge Discovery]
Extraction of relevant information from large
amounts of unstructured textual data
through automatic pre-selection based on
user defined criteria
[Information Distillation]
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Exam Question #1
What are the two aspects of Text Mining
when applied to customer complaints?
Knowledge Discovery: Discovering a
common customer complaint in a large
collection of documents containing customer
feedback.
Information Distillation: Filtering future
complaints 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
What are some examples of unstructured
textual collections used in Text Mining?
Customer letters
Email correspondence
Phone transcripts
Technical documentation
Patents
Many others
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