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Learn DIALOG commands, search strategies, and connectors for comprehensive, scholarly, and technical searches online. Truncate terms, use Boolean operators, and unlock advanced search capabilities for efficient information retrieval.
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LIS618 lecture 1 Thomas Krichel 2003-09-20
Structure of talk • Recap on Boolean • Before online searching • Working with DIALOG • Overview • Search command • Bluesheets • Basic and additional index
before a search I • what is purpose • brief overview • comprehensive search • What perspective on the topic • scholarly • technical • business • popular
before search II • What type of information • Fulltext • Bibliographic • Directory • Numeric • Are there any known sources? • Authors • Journals • Papers • Conferences
before search III • What are the language restrictions? • What, if any, are the cost restrictions? • How current need the data to be? • How much of each record is required?
two steps in DIALOG • step one: select databases (aka files) to look at • step two: perform searches on the selected databases • You may wonder why one does not have one single step like in a search engine. Discuss. • today we concentrate on the second step
working on selected files • We assume that we have selected database that we know and we look at the search interface on the selected database. • The database selection process is a bit more complicated, covered next week. • First, let us login and look at the command prompt. • Then we select the first database (file) with the begin command
The begin command • As its name suggests, usually the first command. • begin number, number,… • selects files with numbers number • Once they are selected they can be searched. • Now select the ERIC "begin 1" • "Begin 1" can be abbreviated as "b 1"
Substeps in the second step • Identify search terms • Use Dialog basic commands to conduct a search • View records online or print the results
the 's' (select) command • Once issued the "begin" command to select a database, we issue the "s" command on the database. • "s query_terms" where query_terms are the query terms • This will search the index of selected database in full-text view for the query issued • It will not find any of the following: "an and by for from of the to with". They are stop words.
connectors • If you want to use several keywords there are three ways • you can truncate search terms • you can build an expression by putting several keywords together. This is achieved by DIALOG's connectors. • you can combine several expressions with the use of Boolean operators • we will cover this is in turn now
truncation of terms • Open Truncation • "select path?" retrieves all words that begin with path: paths, pathos, pathway, pathology • Controlled-Length Truncation • "select path??" retrieves the root and up to two additional characters: paths, pathos
truncation of terms II • Embedded Character truncation can be used for variant spellings: • "select organi?ation" -> organization organisation • "select fib??board" -> fiberboard fibreboard • This truncation feature is also useful for searching for unusual plural forms: • "select wom?n" -> woman women • You can also do prefixes by putting the ? in the beginning. • "?mobile" -> automobile metamobile
Use of connectors • Connectors are used to put several words together. • One instance where this is useful is when you have words that on their own mean different things. • For example "mate" is a herbal beverage consumed in South America. Looking for mate on the Internet retrieves a lot of singles' pages.
example: terms related to "mate" What other terms to be used? • matear (drink mate) • matero (mate drinker) • cebar (prepare mate) • cebador (mate preparer) • yerba (mate herb) • bombilla (mate straw)
connectors I • '(W)' requires terms to appear one after the other next to each other e.g. 'yerba(W)mate?' matches "yerba mate". • '(i W)' where i is an integer, means followed by at most i words, e.g. 'ceba?(3W)mate?' matches "cebar un maravilloso mate" but not "cebador guapo mirando un buen mate"
connectors II • '(N)' requires terms to be next to each other e.g. 'yerba(N)mate?' matches "yerba mate" or "mate yerba". • '(i N)' where i is an integer, means proximity by at most i words, e.g. 'ceba?(3N)mate?' matches "cebar mate" or "matear con la cebadora". • '(S)' searches for the occurrence of connected terms in the same paragraph.
using Boolean operators • In your query, you can combine several expressions with Boolean operators • Example: "S LIBRARY(W)SCHOOL? AND DISTANCE(W)EDUCATION" • But I usually do not issue such fancy queries.
executing several searches • there can be several searches done sequentially, and the results sets are saved by the system. • Each time the system assigns a set number, Si, • These can be combined in Boolean expressions, e.g. 's S1 or S2 and S3' • Remember that Boolean operations are set-theoretic!
Boolean operators on sets • when using Booleans, be aware that "and" has higher precedence than "or". • Thus: a or b and c is not the same as (a or b) and c but it is a or (b and c) • use parenthesis when in doubt
DS (display sets) • This command can be executed any time to review the sets that have been formed since the last B (begin) command. • This can be useful to review your search history.
the target command • "target set" where set is a search result set creates a subset of the "statistically most relevant results" in the original set. • I have not seen details about how this subset is computed. • new result set is being formed.
display: the type command type set/format/range • set is a result set • format is a format • range can be • start – end • start is a record number to start • end is a record number to end • all
standard delivery formats • 2 -- full record except abstract • 3 or medium – citation • 5 or long – full except full text • 6 or free – title and dialog number • 8 or short – title plus indexing terms • useful to find other indexing terms • 9 or full – everything • KWIC or K – keywords in context
options for delivery • I once tried to email results to me, to no avail • You can save the html of the search results in the browser. • You can print the results within the browser.
http://openlib.org/home/krichel Thank you for your attention!