LIS 663 Basic Database Searching

4. Menu-driven, command-driven and natural language searching

Dr. Péter Jacsó

Fall 2015

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

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

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

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

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

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.

 

Jacsó

Jacsó

Jacsó

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

Jacsó

Jacsó

Jacsó

Are You Crazy, restricting to the

descriptor field and with an OR operator?

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

Even the one with 47% is pretty relevant

Jacsó

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

Jacsó

Jacsó

Jacsó

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

Jacsó

The PubMed Approach

(It is the free version - ironically, used MetaThesaurus

behind the scenes)

Jacsó

Jacsó

Jacsó

Jacsó

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

Jacsó

Jacsó

Jacsó