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1 Advanced searching a variety tricks of the trade Tefko Saracevic

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1 1 Advanced searching a variety tricks of the trade Tefko Saracevic tefkos@rutgers.edutefkos@rutgers.edu; http://comminfo.rutgers.edu/~tefko/http://comminfo.rutgers.edu/~tefko/

2 Searching is still much more an art than a science Main object of searching is to be effective Effectiveness is primarily considered in terms of retrieval that is relevant But there is no such thing as a perfect search This leads to various tactics to achieve certain effectiveness goals & levels Central ideas Tefko Saracevic 2

3 1.Definitions, approaches 2.Search tactics 3.Advanced features 1: Using fields 4.Advanced features 2: Using proximity 5.Case study ToC Tefko Saracevic 3

4 Advanced searches as heuristics 1. Definitions, approaches Tefko Saracevic 4

5 Advanced (Encarta) More highly developed … at a higher stage of development or progress than other similar people or things Advanced searching that about sums it up it is searching at a higher level of complexity without which search goals of increased effectiveness cannot be achieved Definitions Tefko Saracevic 5

6 Heuristic (Encarta) problem solving by trial and error a 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 thumb commonsense rules indented to increase the probability of solving some problem Definitions … Tefko Saracevic 6

7 It means that searching is a trial & error process & an iterative process It means that searcher modify a search in response to results or to user rection It is a base for search progression toward more effective results And it is a behind advanced search strategy and tactics Advanced searching is a HEURISTIC process Tefko Saracevic 7

8 Goals of advanced searching Tefko Saracevic 8 – 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

9 Reminder A search strategy is The entire approach to a search – selection of – files and sources to use – approaches in proceeding to search – formats for viewing results – alternative actions if search yields too much too little – problem-solving heuristics Search tactics are A query - command line entered into a system in order to retrieve relevant information & variations in – terms, operators, fields, delimiters & attributes as allowed by a given system – vocabulary & syntax used in conjunction with connectors &/or limiters to search a system Tefko Saracevic 9

10 Advanced searching possible at several levels Strategic using different approaches to fit circumstances or context independent of but adapted to a system used 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 Tactical using system features to the hilt to achieve given objectives – but as said, features may & do differ from system to system Reminder: Search tactics (action choices): – choices & variations in search statements, query – terms, connectors, attributes … – using capabilities of a system to the hilt to achieve desired results Tefko Saracevic 10

11 Various ways of approaching an advanced search 2. Search tactics Tefko Saracevic 11

12 NameMostly used for 1. Speed search (also called Briefsearch, meatball search, quick & dirty search) Questions: usually simple Requirement for answers: brief, not comprehensive Effort: not willing to spend much. Little preparation required Extension: possibly also used as a starting point for ill defined questions or more complex searches to see what works, what is there, & for relevance feedback to proceed with other tactics 2. Building block search Questions: usually complex & fairly well defined Requirement for answers: more comprehensive Effort: willing to spend quite a bit, particularly in preparation Extension: excellent to proceed with relevance feedback to citation pearl growing or refinements 3. Citation pearl growing search Questions: usually complex & not that well defined Requirement for answers: comprehensive Effort: willing to spend a lot, particularly in examination of answers & following & evaluating citation trails Extension: good to proceed with building block tactics Some major tactics Tefko Saracevic 12

13 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 & most prefered by users generally Speed search Tefko Saracevic 13

14 Speed search is not a be all and end all But it could be a very effective beginning – to do initial exploring and getting ides about sources, contents, type of documents, magnitude … – to find some relevant documents and proceed from there – and then to proceed with refining searches using other tactics You do a speed search, examine results, maybe do more & examine again and on that basis refine succeeding searches & tactics However …for a complex search Tefko Saracevic 14 Use it as a classic form of feedback

15 Commonly used search tactic – start small & then build upon results identification: each important concept a search is identified; also facets, such as fields to be searched are identified elaboration: for each concept further terms are identified combination: search starts with one or just a few concepts & associated; as it progresses additional concepts & facets are connected using appropriate Boolean operators &/or attributes iteration: as a search proceeds terms to concepts may be added, new concepts, created & combined; fields added or dropped You build heuristically & modify the query as you go along adding, changing concepts, their elaborations, and facets/fields Building block search Tefko Saracevic 15

16 Concept A Term A 1 Term A 2 Term A n … Building block search - illustration Tefko Saracevic 16 Concept B Term B 1 Term B 2 Term B n … Concept C Term C 1 Term C 2 Term C n … Facets/fields Field/limit F 1 Field/limit F 2 Field/limit F n … 1.From a question concepts A, B, C... are identified – terms that could be further analyzed 2.For each concept search terms are added – narrower, broader, related, synonyms, near synonyms - all these are connected with OR 3.Concepts together with their terms are connected with AND 4.Fields and limits may be added to any or all concepts or terms AND OROR

17 Dialog worksheet helps in planning Tefko Saracevic 17 Enter question Select databases Elaborate terms Reflect goals Specify commands

18 Concepts in building block searches can also be identified not only from a question but from resulting documents from a speed search – thus concepts C, D … could be specified after a previous speed search, elaborated, & then added to a subsequent building block set of concepts – same with facets & fields Connecting tactics Tefko Saracevic 18

19 A search can start with using one of the concepts and its elaborations & then adding others – this way it proceeds from broad (one concept) to narrower by adding other concepts – and reviewing – facets and fields can be added still more narrowing – evaluated as one receives answers – limits/fields can be added at any search, narrowing it further – used to increase precision & focus Same can be done in reverse from narrow to broad to by subtracting concepts from a comprehensive search – used to increase recall & focus Narrowing tactics Tefko Saracevic 19

20 Narrowing schematic Tefko Saracevic 20 Concept A Term A 1 Term A 2 Term A n … Concept A Term A 1 Term A 2 Term A n … Concept A Term A 1 Term A 2 Term A n … Concept B Term B 1 Term B 2 Term B n … Concept C Term C 1 Term C 2 Term C n … Concept B Term B 1 Term B 2 Term B n … + + + add to any Facets/fields Field/limit F 1 Field/limit F 2 Field/limit F n … + 1 st search 3 rd search 2 nd search 4 th, 5 th … search + = AND

21 Citation pearl growing search What? aims It means what the name implies: you start with a nugget & grow upon it Starts with a few records of high relevance Looks at references or who cites it to find more Aims for more recall Avoids subject terms, indexing & language When to use it When word lists or thesauri are not available When there isn’t a large recall after doing some searching When a user has one or two good articles and wants to find more like them When a topic is hot with a breakthrough paper Tefko Saracevic 21

22 It depends on citations over time Backward chaining (back in time) Following up references in articles of interest – moving backward in successive leaps through reference lists Could be linked to co- citation – authors cited together Popular in social sciences, humanities Citation tracking (forward chaining in time) Who has cited a given document, author, journal, institution – moving forward in time from the publication of the item Used also to indicate impact – higher citation rate assumed higher impact Popular in sciences Tefko Saracevic 22

23 Tools giving citation links particularly Web of Science, Scopus & Google Scholar Invaluable for citation pearl growing – Citation indexes in various subjects (law, science …) provided that for a long time even before computers – But it exploded with automation Now some search databases provide support for that search tactics – integrated with subject searching e.g Scopus, even Google Scholar – easy to jump from subject searches to references to citation tracking to sources to authros Citation indexes Tefko Saracevic 23

24 Using fields 3. Advanced features 1 Tefko Saracevic 24

25 Any & all vendors & search engines have advanced search features – none are without them In principle most are the same in that they cover similar fields in records 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 but once you know them well in a few you generalize & adapt to others In fact Tefko Saracevic 25

26 Fields & advanced features Common fields beyond subjects – author, source, year, institution, type of publication, country, etc Some are used to search on another dimension – e.g. authors, sources Others to limit subject & other searches – e.g. dates, language Everybody has fields – & they are critical for advanced searching – it starts with fields How displayed for searching differs greatly – now mostly in menus added automatically – but also available as commands Tefko Saracevic 26 examples

27 Advanced features for Library Literature & Information Science in Wilson Web Tefko Saracevic 27 fields

28 Advanced features for Web of Science Tefko Saracevic 28 fields

29 Advanced features for Scopus Tefko Saracevic 29 fields example

30 Detailed description in: Google Guide Google Guide, particularly in Query Input by Nancy BlachmanQuery Input “ I developed Google Guide because I wanted more information about Google's capabilties, features, and services than I found on Google's website. Google Guide is neither affiliated with nor endorsed by Google.” Advanced features for Google Tefko Saracevic 30 Here is what Google says:

31 Advanced features for Google … Tefko Saracevic 31 fields

32 Many studies show that users (when searching for themselves as end users) use them rarely, if at all, – they do not use Boolean capabilities, availability of searching by given fields, restricting of searching by available delimiters etc. But professional searchers use them a lot Use of advanced features Tefko Saracevic 32 Use of advanced features is one of the hallmarks of professional competencies

33 Using proximity of terms 4. Advanced features 2 Tefko Saracevic 33

34 Proximity Searching for – terms x words apart one after the other or in any order – terms in same sentence, paragraph, field Improves precision – zeros in on specific names, expressions Important for searching – particularly for users in fields with set terminology Connected with phrase searching Simple idea but handled very differently in different databases – to find how handled must go to Help Tefko Saracevic 34 examples

35 Phrase and string searching (similar to proximity) from Help Tefko Saracevic 35

36 Proximity & phrase operators (from Help) Tefko Saracevic 36

37 from Help Tefko Saracevic 37

38 Stop words Words that databases and search engines choose to ignore – for searching – they will note their position but not include in the index – some of them also for indexing – they will not index them to start with Different databases use very different lists of stop words – and handle them differently Dialog has 9 stop words: – AN, AND, BY, FOR, FROM, OF, THE, TO, WITH How about others? – lets see Tefko Saracevic 38 examples

39 Stop words important to know what they do NOT search automatically [from their Help pages] Tefko Saracevic 39

40 Stop words – handled very differently Tefko Saracevic 40 WoK has some 200 stop words that are ignored while searching even for phrases Watch out!

41 Stop words – again handled differently Tefko Saracevic 41

42 My own question & search – reality show 5. A case study Tefko Saracevic 42

43 Question & context this is a real question & reason I had Question Search engines offer a number of features for searching. They also retrieve a large number of answers. How much are these advanced features used? How many pages do people look at? Context I am interested in studies that have actual data. To be used for update of bibliography in this course and for discussion in a lecture book on relevance in information science that I am currently writing – support for broader conclusion Tefko Saracevic 43

44 Databases used I used first Library Literature and Information Science – available at RUL – did not get anywhere really so I lost patience & switched Then I used Scopus – not available at RUL any more, but have class access All results are from Scopus Tefko Saracevic 44

45 First I did a speed search that led me to making building blocks Tactics Selected a basic concept from the question Results I enlarged the search concepts & terms from index terms found in a few examined documents that seemed relevant Tefko Saracevic 45 Search search engines advanced search Web Web searches Online searching Web queries Web sessions Methods Transaction log analysis Search log analysis

46 This resulted in Quite a broad search and a lot of results, so I went to limit to certain fields and dates Selected to add to search as limitation: Tefko Saracevic 46 Facets/fields social sciences only last two years and later to articles with a lot of citations – shows impact

47 One of the searches Tefko Saracevic 47 Limit years Limit area Choose fields

48 Examined about six pages of results, here are three major selections Tefko Saracevic 48 These two did not have any results, but were useful for the class, so I included them in the bibliography This was toward the end but it turned to be a mother lode, not only for having statistical results but for citations

49 Here is the mother lode abstract with a number of features for further searching Tefko Saracevic 49 for entry in bibliography looked at references looked at citations clicked on authors

50 Leads to further things: references, index terms, cited by, related works Tefko Saracevic 50 ideas for index terms cited by related works

51 Articles that cited it start of the list, newest ones first - with a number of features to explore further Tefko Saracevic 51 to examine

52 Multiple use of tactics & results Search tactics used: Speed search Building block search Citation pearl search references (backward chaining) cited by (forward chaining) Relevance feedback Results used for: Got a few references to include in class bibliography Got data to include in lectures and in the future book And example to illustrate topic for this lecture Tefko Saracevic 52 It was what Marcia Bates calls berry-picking search

53 Conclusion: searching is both Tefko Saracevic 53


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