Step 3.3: Partial Matches
Flip 2nd indicators
During the MARS 2.0 authority matching process, partial matches are found for subject headings in which not all of the subject heading has been authorized.
Frequently, enough of the subject heading has been validated to warrant changing the 2nd indicator to reflect the match found. Even though the rest of the subject heading may not match (likely due to LC not creating authority records for every possible subdivision on a subject heading), libraries can still have the 2nd indicators flipped:
bib subject heading: 650 4 $a English language $x Foreign elements $x Greek $v Textbooks. closest match sh 85043541: 150 $a English language $x Foreign elements 2nd indicator changed to 0 for partial match: 650 0 $a English language $x Foreign elements $x Greek $v Textbooks.
Note: Only subject headings (6XX) are candidates for having their 2nd indicator flipped when a partial match is found. Headings will also be updated when partially matched.
Assuming you have chosen to match a certain thesaurus against another and flip 2nd indicator to match results, this table will show how that matching will work. Common examples of this include matching Juvenile or Local headings against Library of Congress headings and updating.
|Change Indicator on Match Rules||Partial Subject Flip Rules|
|Match Result||Flip 2nd ind on match||No Flip 2nd ind on match||Allow Partial Subject Flips||Do not allow partial flips|
|Full Match||Will Flip||Will Not Flip||Will Flip||Will Flip|
|Partial Match||Depends on Partial Flip rule||Will Not Flip||Will Flip||Will Not Flip|
|Non Match||Will Not Flip||Will Not Flip||Will Not Flip||Will Not Flip|
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