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LIS 663 Basic Database Searching 4. Menu-driven, command-driven and natural language searching Dr. Péter Jacsó Fall 2015.

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Presentation on theme: "LIS 663 Basic Database Searching 4. Menu-driven, command-driven and natural language searching Dr. Péter Jacsó Fall 2015."— Presentation transcript:

1 LIS 663 Basic Database Searching 4. Menu-driven, command-driven and natural language searching Dr. Péter Jacsó Fall 2015

2 Why discuss it in LIS 663?  Even professionals crave it  The ugly reality of "controlled" vocabularies  Content problems, Software problems  Google's enormous appeal  Generation Y = Convenience-generation  "Nurturing" attitude - did you mean?  What is NL ? How does it work? Jacsó

3 How does NL work?  Matching Query Terms (QTs) against Documents  Using statistical analysis not Boolean yes/no, not equal weight  Relevance ranking by  Frequency of QTs in source document (or surrogate!)  Frequency of QTs in database  Distance of words + position of QTs + font style of QTs (yes, I am not kidding)  What did Susan Feldman say about good relevance ranking? Jacsó

4 Feldman's aphorism  A search engine based on good relevance ranking finds what You asked for You almost asked for You didn't ask for but wish you had  The price is decreased relevance  What did Nick Tomaiuolo & Joan Packer test prove? Jacsó

5 Tomaiuolo & Packer test 100 test searches on Ebsco ASE in Boolean and NL mode First 10 hits examined Relevance: Boolean (9.3) NL (9.63) - so why bother? NL often 10 of 10, but range sometimes plummeted NL overestimates frequency of one of the QTs Little overlap or no overlap bw Boolean and NL The oil spill example – Boolean: 1,146 articles, NL: 250 articles, but …. Jacsó

6 Traditional Query Formulation  Breaking info need into concept groups  Looking up thesaurus for descriptor terms  Including some free-text terms  OR-ing terms within concept blocks  AND-ing sets created for concept blocks  Refining steps above  Living happily ever after Jacsó

7 Real Query Formulation Can I help you? I guess what I am looking for is something to read for writing my homework about the cultural differences in the perception of conjugal violence. I donno what this conjugal thing is but Google would know, wouldn't it? It probably would, but would you try some databases we have licensed to nurture our students? Are you interested in the legal, social, psychological, gender studies or diversity angle of the issue? Would you like some scholarly journal articles, or conference papers, or general interest magazine articles ? I am not interested in this at all, my […] instructor just wants me to turn in a paper to get my A+ grade. I can throw in an excuse coupon about something as I have not yet totally depleted my collection. I'll just Google it, bye now.

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11 The Traditional Professional Searcher (who learned basics of DIALOG in a LIS school) Jacsó

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13 Are You Crazy, restricting to the descriptor field and with an OR operator?

14 The smart information professional ( who took Advanced Database Searching in UH LIS and did not file a complaint for course distress) She throws at Knowledge Finder's MEDLINE a very vernacular query to see what it can endure Jacsó

15 Even the one with 47% is pretty relevant Jacsó

16 The top three records identified as the ones with highest relevance are very good at first sight Jacsó

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19 If you install the desktop version of the KF engine you'll have more fun Jacsó

20 The PubMed Approach (It is the free version - ironically, used MetaThesaurus behind the scenes) Jacsó

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24 But its Academic Live (now dead) version was low IQ in many regards Jacsó

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