© Tefko Saracevic 1
All you wanted to know …
Advanced searching
© Tefko Saracevic 2
Principles of Searching
Definitions
Advanced (Encarta)
More highly developed …at a higher stage of development or
progress than other similar people or things
Advanced searchingthat about sums it up
it is searching at a higher level of complexity without which search goals cannot be achieved
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Principles of Searching
Definition
Heuristic (Encarta)
problem solving by trial and errora method of solving a problem for which no formula exists,
based on informal methods or experience, and employing a form of trial and error (iteration)
using or arrived at by a process of trial and error rather than set rules
a rule of thumbcommonsense rules indented to increase the probability of
solving some problem
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Principles of Searching
Advanced searching is a HEURISTIC process
• It means that searching is a trial & error process & an iterative process
• It means that searcher can modify a search in response to results or user
• It is a base for search progression toward more effective results
• And it is a behind advanced search strategy and tactics
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Principles of Searching
Goals of advanced searching
– achieve higher levels of effectiveness• getting more relevant, missing more irrelevant stuff
– and at higher level of efficiency• saving on overall time, cost, effort
– center search toward answers & resources most likely to be effective
• also: focus unfocused searches &• get ideas how to proceed
– use all available system features for goals– act as an professional (extreme) searcher
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Principles of Searching
In fact
• Any & all vendors & search engines have advanced search features– most studies show that users use them rarely, if at all
• In principle most are the same • But in application they differ from vendor to
vendor, engine to engine – sometimes greatly– need to be learned individually. What a bummer!– cannot be taken that what & how works in one works
elsewhere – even though similarities are there
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Principles of Searching
Levels of advanced searching
• Advanced searching possible at several levels– strategic
• using different approaches to fit circumstances or context independent of but adapted to a system used
– tactical• using system features to the hilt to achieve given objectives• but as said, features may & do differ from system to system
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Principles of Searching
Reminder
• Search strategy (big picture):– overall approach to searching of a question
• decisions on search resource(s), content & format• variations in these as a search progresses
• Search tactics (action choices) (small picture):– choices & variations in search statements, query
• terms, connectors, attributes …• using capabilities of a system to the hilt to achieve
desired results
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Principles of Searching
• The entire approach to a search – selection of– files and sources to use– approaches in proceeding to search & combining
• search terms• operators to use• fields to search
– formats for viewing results– alternative actions if search yields
• too much• too little
– problem-solving heuristics
A search strategy is
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Principles of Searching
• A query - command line entered into a system in order to retrieve relevant information– terms, operators & attributes as allowed by a given
system– vocabulary & syntax used in conjunction with
connectors &/or limiters to search a system
• Again: depends on a system how it is done– for example, a search statement in DIALOG might
be: b 47; ss (garbanzo? or chickpeas) and (hum?us or humus)
– how would you do that in ?
Search tactics is
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Principles of Searching
Some major strategies
• Briefsearch – also sometimes called
meatball search or quick & dirty search
• Building block search • Citation pearl growing
search
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Principles of Searching
• Takes little planning & is fast– searcher gets on to the system quickly, & enters terms
using default (or simple Boolean) operators – only a few terms are used– there is no or little reiteration & limited interaction
between searcher & system
• Can also be used for verification purposes• Results can be examined for relevance feedback• Not recommended for comprehensive searches• Widely used by users generally
Briefsearch
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Principles of Searching
• Commonly used search strategy– start small & then build upon results
• identification: each important concept or facet of a search is identified
• elaboration: for each facet terms are identified • combination: search starts with one or just a few facets;
as it progresses additional facets are connected using appropriate Boolean operators &/or attributes
• iteration: as a search proceeds terms to facets may be added, new facets, even subfacets, created & combined
• You build heuristically & modify the query as you go long adding, changing facets
Building block strategy
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Principles of Searching
Going about building blocks
Facet 1REGULATION
FCC
regulation
market structures
regulated industries
Facet 2TECHNOLOGY
technology
technical impact innovation technological change
Facet 3TELECOMMU-NICATION
communicationsatellitemicrowave
telephone
cellular phonemobile radio
AND
OR
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Principles of Searching
Getting higher recall
Building block (or multiple facet) searching assume movement from lower to higher recall – getting more stuff that is relevant, but precision may be lowered
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Principles of Searching
• Another common strategy• It means what the name
implies: you start with a nugget & grow upon it
• Starts with a few records of high relevance
• Aims for more recall
Citation pearl growing
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Principles of Searching
How to…citation pearl growing
• Bibliographic & other information is obtained for a relevant (model) document(s) after a Briefsearch– user is often the source of the model document(s)
• Terms (pearls) are selected from the documents to build facets
• Search proceeds iteratively with examination of new relevant documents to enlarge or modify facets– use synonyms and Boolean ‘or’ to create more facets– preserve sets for additional interaction
• This strategy works best if user is present or frequently consulted about results
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Principles of Searching
When is citation pearl growing good to use?
• When word lists or thesauri are not available• When there isn’t a large recall after doing a briefsearch• When a client has one or two good articles and wants to
find more like them• When a topic is new and no descriptors are established
to represent the concept
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Principles of Searching
Advanced searching on the web
• Needs to be adapted to differences – coverage not specified; vastly different from one
source, engine to another– no controlled vocabulary– output ranked by unknown methods & criteria for
“relevance”– building blocks may be indicated by “similar pages” or
“more from this site” or some such– some provide clusters to narrow searches– features, capabilities, specifics differ
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Principles of Searching
A few web search guides of many
• Advanced web searching Greg Notes
• Finding information on the web U of California, Berkeley
• Googleguide advanced operators Nancy Blachman
• Four NETS for better searching Bernie Dodge
• Web search tutorial Searchenginez
• How to choose a search engine or directory SUNY at Albany
• Search the web more efficiently Web Design in New York
• Finding information: search engines Phil Bradley
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Principles of Searching
Beware: search engines are not only about search
• Yes, search is (still) their core, but they are in many other businesses built upon search & these affect what & how of searching for us– they are corporations, commercial entities
• have to make money, mostly by ads & placements
– but provide many other services• selling, licensing software• email, messenger • add-on utilities – like your desktop search functions, toolbars
– many of the additional stuff is provided free, but there is no such thing as free lunch
• basically they are about how search engines can get us to continue to use their product
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Principles of Searching
In other words
• Buyers beware!
• Searchers be aware!
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Principles of Searching
A few search sources for the fun of it
• Shakespeare & Internet Search Tools & Resources
• Picsearch picture searching
• US government official web portal “Whatever you want or need from the U.S. government”
• Special Search Engines Leiden U, Netherlands, probably the longest page on the web – a bit out of date
• Yahooligans! the web guide for kids
and a study: Bilal, D. (2000). Children's use of the Yahooligans! Web search engine. Journal of the American Society for Information Science, 51 (7), 646-665 [available at RUL]
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Principles of Searching
Role & importance of interaction in searching
“At a fundamental level, information retrieval is inherently interactive.”
“This becomes apparent as one considers that the process revolves around a series of activities that an information searcher engages in with an information environment.”
Savage-Knepshield, P. A. & Belkin, N. J. (1999).
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Principles of Searching
Interaction: key to effective searching
• Interaction between – user and searcher – searcher & information system– user & searcher with information objects– searcher with support materials (thesauri, codes, etc.)– user & searcher with environment– user & searcher with valuation of results
• All play a part in retrieving satisfying results• Iteration is a result of interaction
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Principles of Searching
Interactive process
User task question useContext
User task question useContext
Query
Search
Sources
IterationEvaluation
Searcher
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Principles of Searching
Ask yourself some questions
• What strategies & tactics have I developed for effective searching?
• What heuristics?
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Principles of Searching
For a questionask yourself more questions
• What do I do first?• What files/systems should I use?• Should I start broad or narrow?• What will my search statement be?• How much material do I or user need?• What format do I or user want for results?• How will I modify & adjust results?
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Principles of Searching
Happy advanced