Information search

1. SEARCH TECHNIQUES
Dr. Pawan Agrawal
Dr. APJ Abdul Kalam Government College
Silvassa

2. IS SEARCHING ACADEMIC DATABASES JUST
LIKE DOING A SEARCH ON GOOGLE?
• You could search Academic databases by just throwing in queries
comprising various words and phrases, and hoping for the best
• Or you could be much more precise, by structuring your search
queries using search tools and operators

3. HOW?
• For word searching, you can select:
• how the words are combined
• whether any words are to be excluded
• whether the words have to be next to or near to one another, and
how close they must be
• and you can search using part words, phrases and brackets
• Or you can search using classifications,
numbers, dates or names
• Or you can combine any or all of these

4. SEARCH COMPARISONS
Acid Halogen
Acid
Hydrochloric
Acid
Google 3,760,000,000 240,0000 531,000
Cross Reference - - 80,500
Blackwell
All Journals 98,190 552 1,068
Chemistry 18,195 69 79
All Journals with “” - 1 1,018
Chemistry with “” - 0 78

5. FIELDS
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6. FIELDS
• You can also decide which sections – or fields - of the database you
wish to target with your search, eg
• the full text
• the front page
• the title
• the abstract
• the Journal Name
• the Publication Year
• Author
• combinations of these
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7. IN SHORT:
• To structure search queries:
• use operators (Boolean, Proximity, Wildcards and truncation)
• use phrasing and nesting
• To direct a search to selected areas of the database:
• use field operators to specify which fields are to be searched
• These are the topics we’ll be discussing in more detail
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8. GEORGE BOOLE
• Philosopher and mathematician, born in 1815
• Famous for having developed Boolean algebra, the
basis of digital computer logic
• Derived from this algebra are the most commonly
used operators in online searching - Boolean
operators
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9. BOOLEAN OPERATORS
• The most important Boolean operators
are:
• AND
• OR
• NOT
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10. EXAMPLES
• So if we are searching for documents relating to electric cars, we can use
the search query electric AND car
•  only documents having both the words “electric” and “car”
• But if we are looking for documents relating to cars or trucks, we will
need to search for car OR truck
•  any document having either the word “car” or “truck” or both
of these words or all three of these words
• If no operator is specified, many databases automatically assume that
you mean AND, ie:
• electric car  only documents having both the words “electric” and
“car”
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11. BOOLEAN OPERATORS : AND
electric
car
electric
AND
car

12. BOOLEAN OPERATORS : OR
car OR truck

13. BOOLEAN OPERATORS : NOT

14. PROXIMITY OPERATORS
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15. PROXIMITY OPERATORS
• If we are searching for electric cars, as in the previous example, we do
not really want to pick up documents which simply contain, anywhere
in the document, the word electric and the word car
• What we really want is to find documents which have the words
electric and car in the same part of the document.
• So we can use proximity operators.
• Some databases use the operator NEAR

16. PROXIMITY OPERATORS IN
PATENTSCOPE
• electric NEAR car documents having both the words
“electric ” and “car” within five
words of each other
• To select a different number of words n, use the command “~ n”
• electric NEAR car ~ 10  documents having both the words
“electric ” and “car” within ten words of
each other
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17. PHRASING
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18. PHRASING
• Searching words using the AND operator can give false drops eg one of
the documents found when searching “bicycle AND stand” describes
• an isocyanate compound .. bicycle (2.2.1) heptane … left to stand at
room temperature
• To avoid this, need to specify that bicycle and stand are near to each
other, so could use the proximity operator NEAR as in the previous
example
• But really we only want bicycle and stand next to each other
• So search the phrase “bicycle stand“ ie with the words of the phrase
enclosed in quotation marks
• Cautionary note phrases such as “electric car“ - will be searched as just
that, so won‘t pick up the phrase “electric or hybrid car“. So here need to
go back to proximity operators
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19. WILDCARD OPERATORS AND
TRUNCATION
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20. WILDCARD OPERATORS AND
TRUNCATION
• If searching in the area of electrical technology, you might wish
to include all the words electric, electrical, electricity, electronics,
electrostatic etc
• Could use the Boolean operator OR, ie search electric OR
electrical OR electricity OR electronics OR electrostatic
• Better to truncate - ie search “electr”, with a wildcard operator
to look for all words beginning with electr . This is called right
truncation
• Different search systems use different symbols as wildcard
operators – for instance * or ? or % or $
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21. CONCLUSION
• When searching Academic databases, it is essential
• to think carefully about what exactly you want to search
for
• and to express it accurately and unambiguously
• The computer will then do exactly as you ask it to;
nothing more and nothing less
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