searching periodical databases mit 026b winter 2002
TRANSCRIPT
Searching Periodical Databases
MIT 026B
Winter 2002
Database Records
Accession NumberTitleAuthorJournalLanguageAbstractDescriptors
“Record”
“Fields”
CONTROLLED VOCABULARY
AuthorsDescriptors
NATURALLANGUAGE
TitleAbstract
Truncation
Natur*
Nature
Natures
Natural
Naturalist
Naturalistic
Naturalism
Wildcards
M?cDonald
McDonald
MacDonald
Positional Operators
ADJ
ADJ3
WITH
NEAR
Training cats and dogs as pets
Search for articles about:
Training cats and dogs as pets
Training DogsCats Pets
Search for articles about:
List of Documents
How to train a dog to kill people.
The difference between dogs and cats.
Training cats as pets.
Training dogs as pets.
Training your skunk to be a pet.
Why dogs make good pets.
How to train a cat to kill people.
List of Documents
How to train a dog to kill people.
The difference between dogs and cats.
Training cats as pets.
Training dogs as pets.
Training your skunk to be a pet.
Why dogs make good pets.
How to train a cat to kill people.
List of Documents
How to train a dog to kill people.
The difference between dogs and cats.
Training cats as pets.
Training dogs as pets.
Training your skunk to be a pet.
Why dogs make good pets.
How to train a cat to kill people.
List of Documents
How to train a dog to kill people.
The difference between dogs and cats.
Training cats as pets.
Training dogs as pets.
Training your skunk to be a pet.
Why dogs make good pets.
How to train a cat to kill people.
Document/Term Matrix
Train* Dog* Cat* Pet*
Doc. 1 x x
Doc. 2 x x
Doc. 3 x x x
Doc. 4 x x x
Doc. 5 x x
Doc. 6 x x
Doc. 7 x x
Document Sets
“Train”= {d1, d3, d4, d5, d7}
“Dog” = {d1, d2, d4, d6}
“Cat” = {d2, d3, d7}
“Pet” = {d3, d4, d5, d6}
“Dog” AND “Cat”
d1
d4
d6d3
d7
d2
dog AND cat = {d2}
“Dog” OR “Cat”
d6
d1
d4
d2d3
d7
dog OR cat = {d1, d2, d3, d4, d6, d7}
“Dog” NOT “Cat”
d6
d1
d4
d2d3
d7
dog NOT cat = {d1, d4, d6}
Hints for Searching Electronic Databases
• Plan ahead
• Don’t get discouraged
• Be prepared to repeat the search, using different strategies
• Use BOTH free-text AND controlled vocabulary terms
Recall vs. Precision
Low
High
High
Low
Recall
Precision
Search ResultsBuildingBlocks
CitationPearlGrowing
Building Blocks Approach
• Identify the different concepts, or “facets” of the topic you wish to search
• Create a series of terms for each concept• Combine the terms for each concept
together into a single set, using the “OR” operator
• Combine the sets together, using “AND,” “OR,” or “NOT.”
Topic:
Ecological concerns in American poetry
Concept Map
Ecology United States Poetry
Environment* United States Poe*
Ecolog* America*
Building Blocks ApproachConcept 1 Concept 2 Concept 3
Term 1a ORTerm 1b ORTerm 1c
Term 2a ORTerm 2b ORTerm 2c
Term 3a ORTerm 3b ORTerm 3c
ANSWERSET
AND…OR…NOT
Building Blocks ApproachConcept 1 Concept 2 Concept 3
AND…OR…NOT
Successive Fractions ApproachConcept 1 Concept 2 Concept 3
Term 1a ORTerm 1b ORTerm 1c
Term 2a ORTerm 2b ORTerm 2c
Term 3a ORTerm 3b ORTerm 3c
INTERIMSET
AND…OR…NOT
ANSWERSET
AND…OR…NOT
Fun with Your Thesaurus
• Novel (100 citations)
• Narrower terms:– American novel (25 citations)– Bildungsroman novel (25 citations)– Canadian novel (25 citations)– Postmodern novel (25 citations)
Searching the term, “Novel”:
Novel 100
“Exploding” a Term
Searching the citations for a term AS WELL AS the citations for all the NARROWER terms under it
Novel 100
American novel 25Bildungsroman 25Canadian novel 25Postmodern novel 25
200Citations
Citation Pearl Growing
• Start with 1 or a few documents that are KNOWN to be relevant to your search.
• Investigate the descriptors and natural language terms in the documents and develop a list of concepts
• Use these concepts to find more terms, and collect more documents
• Repeat the process as necessary/desired.
Citation Pearl Growing
TitleAuthorAbstract
Descriptors
Citation Pearl Growing
Title
Author
Abstract
Descriptors
Title
Author
Abstract
Descriptors
Knowledge Growth
GeneralRelativity
QuantumTheory
(quantum ADJ theory) AND (general ADJ relativity): 45
45
Knowledge Discovery
VibrationTheory
QuantumTheory
(quantum ADJ theory) AND (vibration ADJ theory): 0
Knowledge Discovery
• The detection of patterns in large data stores which leads to the extraction of previously unknown, potentially useful knowledge.
Knowledge Discovery
VibrationTheory
QuantumTheory