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plp:title_variants [2010/03/17 18:30]
plp:title_variants [2013/04/27 09:09] (current)
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 +====== PLP: Title Variant options ======
 +
 +The page describes the second of the two special options that can be configured for the TITLE primary key. 
 +
 +{{:plp:titlevariants.jpg|}}
 +
 +__Title variants__
 +
 +This option is applied only if a title search retrieves no hits. Title searches often fail because of slight variations in the entry of the title. The options in the Variants section try to make it possible to compensate for these variations, by retrying the title search using slightly different 'versions' of the title. You can select as many of these options as you wish. 
 +
 +The default title query is composed from the 245 field in the MARC record, by extracting subfields $a $n $p $h $b in the order that they appear in the record.
 +
 +Title variants are composed after the default title query is created. For each selected variant option, in the order that they appear on this form, the MARC data is extracted (as described in the next section), normalized, and then compared to the default title, and any other variants that have been thus far created. If the resulting query is not in this list, it is added. If none of the variant options generate a query that is different from the default title query, then no variants will be searched for that record.
 +
 +===== Data Extraction =====
 +
 +__Each 246__--If there are any 246 fields in the record, this will generate an additional title query for each 246, up to a maximum of 9. 
 +
 +__Subfield $b removed__--If the 245 field contains a subfield $b, this will generate an additional title query with $b removed from the default list of subfields that are extracted from the 245.
 +
 +__Data in Square brackets removed__--this will generate an additional title query where any (and all) text that appears in square brackets, except in the subfield $h, is removed from the data extracted from the 245 field.
 +
 +__Subfields in AACR2 order__--this will generate an additional title query (if applicable) by extracting the default subfields from the 245 and arranging them in the following order: $a $n $p $h $b 
 +
 +__Hyphenated words as single words__--If any words in the title contain a hyphen, this will generate an additional title query where any these words are searched without the hyphen; for example, 'Folk-lore' becomes 'Folklore'.
 +
 +__Acronyms and initialisms contracted__--If the 245 contains any initialisms (defined as three or more uppercase letters followed by a period) this will generate an additional title query where the periods are removed from all of the initialisms; for example, 'U.N.E.S.C.O.' becomes 'UNESCO'.
 +
 +__Acronyms and initialisms expanded__--This option is the reverse of the previous one: If the 245 contains any acronyms (defined as two or more consecutive uppercase letters) this will generate an additional title query where periods are inserted between the uppercase letters; for example, 'UN' becomes 'U.N.' Note that after normalization, 'U.N.' becomes 'U N '.
 +
 +__Subfield $p as the title__--If the title field contains a subfield $p, this will generate an additional title query where the only data extracted from the 245 is the subfield $p.
 +
 +===== Matching =====
 +
 +Title variants are searched in the order in which they appear on this form. The order is based on the frequency with which a title variant retrieves hits. In the current version, this order may not be changed.
 +
 +Title variant searching stops as soon as one of the selected variant options retrieves a hit. For example, if all of the title variant options are selected, and the normal title search retrieves no hits, then PLP will perform a title query for the 246(s), and if that search fails, it will perform a title query with the $b removed, etc.
 +
 +===== Statistics =====
 +
 +In the PLP report for the run, statistics for variant title queries are displayed, giving: the number of variant title queries created, the number that were searched (because the default title query retrieved no hits), and the number of variant title queries that retrieved hits from the DB. The objective of reporting this amount of detail is to help you decide which variant queries are most useful.
 +
 +An example variant title report follows.
 +<code>
 +Variant Title Query stats
 +
 +Col 1=Queries created, Col 2=Queries sent to the DB, Col 3=Queries Succeeded
 +
 +Each 246 field as the title:              253 29 15
 +Subfield $b removed:                      250 29 7
 +Data in square brackets removed:          289 2 0
 +Subfields in AACR2 order:                 3 0 0
 +Hyphenated words as single words:         16 3 0
 +Acronyms and initialisms expanded:        35 1 0
 +Acronyms and initialisms contracted:      6 0 0
 +Subfield $p as the title:                 32 5 0
 +</code>
  
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