Search Strategy - I Dr. V. V. Subrahmanyam Associate Professor, - - PowerPoint PPT Presentation

Search Strategy - I

• Dr. V. V. Subrahmanyam

Associate Professor, SOCIS, IGNOU

Search and Search Strategy

• Search: A search is performed to obtain exact
• r related information about a topic / keyword

/ subject area etc., from a repository of information.

• Search Strategy: It is the systematic tactics /

technique to be followed in finding the relevant information on a topic.

Search Results

• Good search results based on :

– well organized information – Use of right search formulation

• A search in a database may be a combination
• f an interactive, iterative and heuristic
• process. Often it is a trial and error exercise.

Stages of Search Strategy

• The stages in database search may be

– Recognition of an information need – Communication of the information need to the information/database service centre – Recording of the search request – Specification of search request – Select the database resource – Formulate query in search language

Contd…

• Perform the search operation
• Modification of search
• Displaying information as per user preference
• Recording/logging the query

Recognition of Information Need

• Defining the need for information by the end-

user in terms of a specific subject, type

• f information / document desired.
• Example: One can specify a bibliographic

reference with or without abstract, or how soon the information is needed and other details.

Communication of the Information need to the service centre

• When search process cannot be done by

the end user and informing it through some media to the Information / Data Service Centre.

Recording of the search request

• Search request with details is recorded in a

search record form (online or printed).

Specification of search request

• End user may suggest some Aids such

as a scheme of classification or a thesaurus covering the subject of the query, subject map, known documents etc..

Select the database resource

• Selection of appropriate database(s) for

best results.

Formulate query in search language

• Formulation of query in the search

language of the database and / or the software used in the creation of the database.

• Appropriate structure and syntax need to

be used.

Perform the search operation

• Perform search on fast access files, involving

indexes to yield best and faster results.

• The end user can assist in the evaluation of

the initial / intermediate search results and provide feedback.

Modification of search

• If necessary depending on the feedback

modification of search strategy and refinement of the search expression can be done.

Displaying information as per user preference

• Selecting the most relevant

reference/abstracts and arranging the result as desired by end-user.

Recording / Logging the query

• The search procedure adopted and the

results obtained can be recorded for future use and analytical studies.

Search Procedure Flow chart (Guinchat and Menou, 1990, p.224)

Search Types

• There are 2 broad types of searches for an

information repository/database:

– Controlled Vocabulary or Index based search – Free text search

Controlled Vocabulary Or Index Based Search

• To search a database using controlled

predefined vocabulary.

• Controlled vocabulary is defined as the set
• f pre-defined terms that are used to

define certain concepts consistently.

• This type of search requires data to be

characterized into controlled vocabulary.

Search involves…

• Displaying the index and selecting the

appropriate terms.

• Entering the search terms

Example

• You can define a list of keywords for

various concepts and give listing of those controlled words as and when needed by the searcher.

Free Text Search

• This type of search is for non-keyword
• riented search.
• Almost all databases allow free text search.
• These are based on the terms as used by the

authors.

• This is relatively a longer process.

Combination of both types

• Combination of controlled vocabulary

search and freetext search is useful many at times.

• If the number of records retrieved by the

indexed based search is large and a further selection from the set may be made by freetext search.

Electronic Searching Techniques

• Using Boolean Operators (AND, OR, NOT)
• Keyword Vs Controlled Vocabulary
• Limiting (by date, publication type, full-text

availability etc..)

• Natural Language Searching
• Nesting (Ex: (Books or Series)AND 2002)

Contd…

• Proximity Searching (Ex: Windows AND

Operating W/I System)

• Thesaurus (connecting the term used by

him/her to the controlled vocabulary)

• Truncation (Wild Cards)

Search Operators

• Boolean Operators (AND, OR, NOT)
• Parentheses (Ex: POLLUTION AND (BIHAR OR

ODHISSA OR TAMILNADU)) to search for “Pollution in either Bihar, Orissa and Tamilnadu

• Truncation(Ex: FOREST$)
• Masking(Ex: Normali?ation) retrieves

Normalisation and Normalization