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LIS618 lecture 8 Credo and Gale Thomas Krichel 2011-11-01.

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1 LIS618 lecture 8 Credo and Gale Thomas Krichel 2011-11-01

2 Credo and Gale Credo and Gale are both reference tools. They have number of digital sources. The precise coverage of the tools is a topic for LIS511. Here we are interested in the search capabilities.

3 credo A reference tool. The documentation of its search interface leaves much to be desired. A formal grammar would help.

4 phrase expression " a b " Phrase Surround two or more words a and b with double quotes to search that phrase. Word order in the retrieved entries is the same as word order in the phrase. (doc) The terms can be words, without truncation and soundex. The phrase expression can then be used with (non) occurrence operators.

5 occurrence operators “+” Must occur. All retrieved entries must contain this word or phrase. If a term or phrase has no prefix operator, + is implied. It is necessary to put the + if a noise word is searched. “^” Should occur. Retrieved entries with this word should rank higher than those without this word or phrase.

6 non-occurrence operators “!” Should not occur. Retrieved entries with this word should rank lower than those without this word or phrase. “-” Must not occur Retrieved entries must not contain this word or phrase.

7 truncation (doc) “*” Truncation Search word variations allowing any number of letters to occur where the * is located. Can be used in front of the word, inside the word or at the end of the word. “?” Wildcard Search word variations allowing any single letter to occur where the ? is located. Can be used in front of the word, inside the word or at the end of the word.

8 truncation The truncation in front of the word does not work. Compare search for “*aarbrücken” with “Saarbrücken”

9 sounds like “~” Sounds like Retrieve entries with words that sound like this word. Useful when the exact spelling of a term is unknown. I have not found a documentation of how this is achieved. This is likely to be language-specific. “Saarbrü~en” does not work. Presumably this can not be used inside a word.

10 example Search for “Saarbrücken” gets you snippet “It was the capital of the counts of Nassau- Saarbrücken...” “Nassau-Saarbrück*” no hits “"Nassau Saarbrück*"” no hits “Nassau and Saarbrück*” no hits

11 Boolean operators The interface allows to enter ‘or’, ‘and’ and ‘not’. Not is “also recognized as” (doc) ‘and not’. “?aarbrücken and NOT Saarbrücken” no hits. “Saarbrücken NOT Saarbrücken” a lot of bizarre hits.

12 fielded searches By default terms are searched in all fields. Fielded searches are possible but there are three fields only – “h:” Entry Heading – “s:” Entry Section Heading – “b:” Entry Body The indicator

13 noise words The noise words a..z (all the individual letters) about also an and are as at be but by from for how in is it of or that the this to was who what where which with why. The default of “must occur” is changed to “should occur” for those words. Three of them are actually reserved words.

14 facetted search When results appear in the browser, a panel to the left shows facets. The facets allow a limitation to the search. Once you restrict to a facet, the facet box appears on top of the results. A click on a facet box x disables the facet restriction.

15 direct facet entry Credo publishes a list of facet tags at http://he lp.credoreference.com/Wiki.jsp?page=Facet% 20tags. When you know the facet tag, you can enter it directly into the search expression. You can use the special f: field

16 the f: field “h:"karl marx" and f:subject_geography” no hits “Laser and f:subject_genref_dict” is the example given in the documentation. It produces no hit. This system fails to impress.

17 Gale This is also a virtual reference system, at http:/ /go.galegroup.com/ps/start.do?prodId=GVRL At the start we are given an advanced search screen. This looks more tuned to the “reference geek”.

18 triple-field start screen We are invited to enter fielded queries for title, keywords and document. As a test, in the title “Saarland” gets no hits, in the keyword 13 hits and in the body of the documents 42 hits. The contents suggests that the documents focus on business.

19 multi-index Gale supports fielded queries. This what they call “multi-index”. These are prominently displayed in the interface. There are also some Boolean selectors displayed that we don’t need to discuss further.

20 multi-index fields KeywordKey fields, including authors, titles and introductory text Document TitleTitles of documents Image Caption Entire DocumentThe full text of documents..

21 multi-index SubjectIndexed LoC subject headings. Publication TitleTitles of eBooks. ISBN AuthorNames of authors, including variants PublisherNames of publishers Edition(cardinal) edition number a Volume Number (cardinal) volume number

22 multi-index Start Page (cardinal) start page. Hyphen can be used to provide a range value. Document NumberThe unique identifier Gale assigns to each document. If given all others are dropped. Title CodeAll editions of a publication as represented by its title code (such as 0HNY or 0BAR)

23 example At id.loc.gov, if you enter “square dance” you will find the subject heading “square dancing”. For “international business enterprises” in the subject index, I only found one document.

24 stop words The documentation states “Stop words are small words that are not indexed. Stop words include such words as a, and, etc., in, of, on and to; the actual list varies depending on how you're searching. Basically, you don't have to think about stop words at all. The system recognizes stop words and knows how to search as if they weren't there.” This can not be true.

25 likely treatment If the query contains a stop-word, the stopword is replaced by a distance connector. Search for “to be or not to be” results in an error “Illegal Query Expression - Boolean operators must be used between terms.” Search for “I have a dream” and “I have an dream” gets different results numbers.

26 punctuation The first thing the documentation considers is the hyphen. The documentation says: “A hyphen (-) used between two words is ignored. However, if you are searching for a word or phrase that normally contains a hyphen, you may include it. “e-mail” “dot-com”

27 email vs e-mail “email” gives 4 results, one is a duplicate. “e-mail” gives 14 results. The formerly duplicated entry is now appears in triplicate. The result sets appear to be non-overlapping otherwise. The duplicate entries have different Gale numbers but appear to have identical citation data.

28 author names In author names, Gale does not search for abbrivaitions Compare – “Marx” – “Paul Marx” – “P Marx” in the author name field.

29 wildcards Gale uses the following truncation operators – “*” for one or more characters – “?” for exactly one character – “!” for zero or one character If only these systems could standardize. We are not told about where they can occur, but we are told to add more letters if they

30 proximity operators These can be used to connect expressions. They are like in Dialog – Wnumber where direction is required – Nnumber where direction need not to be respected Quotes are equivalent to W1. The default connector is N4.

31 Booleans Boolean operators “or” “not” “and” connect expressions composed out of query terms, connectors and wildcards. The parenthesis can be used to enforce an evaluation order.

32 http://openlib.org/home/krichel Please shutdown the computers when you are done. Thank you for your attention!


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