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Discover Emerging and Novel Research Topics. TopicTrend. By: Jovian Lin. Introduction. Formulating a research idea is the 1 st step for success in academia. A worthy research idea must be original and innovative . - PowerPoint PPT Presentation
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TopicTrend
By: Jovian Lin
Discover Emerging and Novel Research Topics
Introduction
Formulating a research idea is the 1st step for success in academia.
A worthy research idea must be original and innovative.
In order to come up with innovative research ideas, researchers have to read a lot of published articles…
… which is time-consuming.
“Is there any shortcut to success?” “No.”
“There are efficient ways to achieve success”
Search Engines in Digital Libraries:
Search engines support information seeking and retrieval.
Introduction
SearchEngine
“Search Query”
List of titles (of articles)
Search
Results
Search engines support information seeking and retrieval.
However, is this enough for the junior researcher?
Introduction
FYP students 1st year PhD students
• Define a research topic (from zero knowledge)• Help in survey• Identify emerging/new research areas to explore• Determine related topics
How useful is this result to the junior researcher?
Junior researchers want:Understand research topics and trends.Recognize HOT topics.Understand how topics interact and influence research activity.
Problem Definition
Junior researchers want:Understand research topics and trends.Recognize HOT topics.Understand how topics interact and influence research activity.
Problem Definition
Enter a search query
View results
Select a few articles to read
Extract new terms fromselected article
CurrentInefficient
Method
Search
Results
Information overload !
Junior researchers want:Understand research topics and trends.Recognize HOT topics.Understand how topics interact and influence research activity.
Problem Definition
Enter a search query
View results
Select a few articles to read
Extract new terms fromselected article
CurrentInefficient
Method
Junior researchers want:Understand research topics and trends.Recognize HOT topics.Understand how topics interact and influence research activity.
Problem Definition
Enter a search query View results
DesiredEfficient Method
Visualization of the research topics
List of HOT research topics (related to the search query)
Do it quick!TopicTrend
Quick Demo
Recruited 4 participants.
Participants:Tested TopicTrend using queries from their respective domains.Rated TopicTrend’s output (w.r.t. their query). [Quantitative]Filled up a questionnaire. [Qualitative]
Evaluation
• Chemistry / PhD• Engineering (Transportation) / PhD• Comp Science (AI) / PhD• Engineering / FYP
Evaluation
Topic ATopic BTopic CTopic DTopic ETopic FTopic GTopic H
10111111
Topic I 1Topic J 1
Score
9/10
Topic A
Topic B
Topic CTopic D
Topic E
Topic F
Topic G
Topic HTopic I
Topic J
“machine learning”
Evaluation
Average score = 68.125%
Quantitative
Evaluation
Questionaire using Five-Point Likert Scale.
1=Disagree, 5 =Agree.
Some examples:“The system was easy to use.”“The system gave interesting results.”“I was able to get a better understanding of the topics.”“I was able to discover trends.”“I was able to discover relationships between topics.”“I was able to discover potential, novel topics.”
Details in Project Report.
Qualitative
4.75 / 5 4 / 5
4 / 54 / 5
4 / 54 / 5
ConclusionTopicTrend is a visualization tool that helps junior researchers:
Understand research topics and trends.Recognize HOT topics.Understand how topics interact and influence research activity.
However, results were mediocre Due to presence of stop phrases (e.g., “problem set”, “proposed model”, etc)
Solutions and Future Work:TF-IDF weight — don’t have to manually enter stop words.
Statistical measure to evaluate how important a word is.The importance increases to the number of times a word appears in the document...But is offset by the frequency of the word in the corpus.
Latent Dirichlet Allocation (LDA) – view each abstract as a mixture of topics. (David Blei)Online LDA – find topics faster than normal LDA; analyze in a stream.Dynamic Topic Models (DTM) – captures the word evolution of each topic over time.
Search by exemplar (instead of search by keyword)Benefits users who have difficulty expressing their query.
ConclusionTopicTrend is a visualization tool that helps junior researchers:
Understand research topics and trends.Recognize HOT topics.Understand how topics interact and influence research activity.
However, results were mediocre Due to presence of stop phrases (e.g., “problem set”, “proposed model”, etc)
Solutions and Future Work:TF-IDF weight — don’t have to manually enter stop words.
Statistical measure to evaluate how important a word is.The importance increases to the number of times a word appears in the document...But is offset by the frequency of the word in the corpus.
Latent Dirichlet Allocation (LDA) – view each abstract as a mixture of topics. (David Blei)Online LDA – find topics faster than normal LDA; analyze in a stream.Dynamic Topic Models (DTM) – captures the word evolution of each topic over time.
Search by exemplar (instead of search by keyword)Benefits users who have difficulty expressing their query.
Thank You
Backup Slides
OpenNLP — a machine learning based toolkit for theprocessing of natural language text.
Used OpenNLP to retrieve a list of NPs.
Implementation
OpenNLPToolsAn article
1. Sentence Detection2. Tokenization3. Part-of-Speech (POS) Tagging4. Chunking and Retrieving NPs
NP A
NP B
NP C
NP D
NP E
NP F
Sentence Detection
Implementation
Pierre Vinken, 61 years old, will join the board as a nonexecutive director Nov. 29. Mr. Vinken is chairman of Elsevier N.V., the Dutch publishing group. Rudolph Agnew, 55 years old and former chairman of Consolidated Gold Fields PLC, was named a director of this British industrial conglomerate. Those contraction-less sentences don't have boundary/odd cases...this one does.
• Pierre Vinken, 61 years old, will join the board as a nonexecutive director Nov. 29.
• Mr. Vinken is chairman of Elsevier N.V., the Dutch publishing group.
• Rudolph Agnew, 55 years old and former chairman of Consolidated Gold Fields PLC, was named a director of this British industrial conglomerate.
• Those contraction-less sentences don't have boundary/odd cases...this one does.
Tokenization
Implementation
• Pierre Vinken, 61 years old, will join the board as a nonexecutive director Nov. 29.
• Mr. Vinken is chairman of Elsevier N.V., the Dutch publishing group.
• [Pierre] [Vinken] [,] [61] [years] [old] [,] [will] [join] [the] [board] [as] [a] [nonexecutive] [director] [Nov.] [29] [.]
• [Mr.] [Vinken] [is] [chairman] [of] [Elsevier] [N.V.] [,] [the] [Dutch] [publishing] [group] [.]
Part-of-Speech Tagging
Implementation
• Pierre Vinken, 61 years old, will join the board as a nonexecutive director Nov. 29.
• Mr. Vinken is chairman of Elsevier N.V., the Dutch publishing group.
• [NNP] [NNP] [,] [CD] [NNS] [JJ] [,] [MD] [VB] [DT] [NN] [IN] [DT] [JJ] [NN] [NNP] [CD] [.]
• [NNP] [NNP] [VBZ] [NN] [IN] [NNP] [NNP] [,] [DT] [JJ] [NN] [NN] [.]
Text Chunking and Extracting NPsText chunking consists of dividing a text in syntactically correlated parts of words.Uses the Tokenization and POS Tagging data.For example:
He reckons the current account deficit will narrow to only # 1.8 billion in September.
Becomes:
[NP He ] [VP reckons ] [NP the current account deficit ] [VP will narrow ] [PP to ] [NP only # 1.8 billion ] [PP in ] [NP September ] .
Implementation
Text Chunking and Extracting NPsText chunking consists of dividing a text in syntactically correlated parts of words.Uses the Tokenization and POS Tagging data.
Implementation
Note the:• B-Chunk• I-Chunk
OpenNLP — a machine learning based toolkit for theprocessing of natural language text.
Used OpenNLP to retrieve a list of NPs.
Implementation
OpenNLPToolsAn article
1. Sentence Detection2. Tokenization3. Part-of-Speech (POS) Tagging4. Chunking and Retrieving NPs
NP A
NP B
NP C
NP D
NP E
NP F
An algorithm to calculate the score of a NP.
Implementation
NP A
NP B
NP C
NP D
NP E
NP F
# (0 ~ 2 years)
# (2 ~ 4 years)
# (4 yrs & beyond)
10
2
1
Score = 10 + 1
10 + 2 + 1 + 20
= 11
33 = 0.333
# (0 ~ 2 years)
# (2 ~ 4 years)
# (4 yrs & beyond)
1
2
10
Score = 1 + 1
1 + 2 + 10 + 20
= 3
33 = 0.090
An algorithm to calculate the score of a NP.
Implementation
NP A
NP B
NP C
NP D
NP E
NP F
Re-rank the list of NPs base on the score.
Implementation
Re-rankNP B
NP D
NP E
NP C
NP A
NP F
New!NP A
NP B
NP C
NP D
NP E
NP F
Implementation
Calculate the relationship strength between NPs byconsidering the common articles (PIIs) that they have.
The more articles they have in common, the thicker the edge.
The End