Step 4.6: Hierarchy
MARS 2.0 staff recommends matching authority records for all levels of hierarchy to improve patron access to the collection. Library of Congress often provides cross-references only in the authority record for the highest level of a hierarchal heading:
bib record with full heading: Puppies - Diseases
see also from 5XX xref necessary to generate proper display: Dogs See also Puppies
An authority record matching the higher-level heading Puppies would not be distributed to you if you chose full headings only.
Full headings only
Some libraries choose full heading strings only because their ILS will not index an authority heading that doesn’t appear in its entirety in a bib record.
MARS 2.0 continues to match the higher level headings and update the bib headings with any flips or other changes that occur.
If you choose full heading strings only, MARS 2.0 only pulls authority records for those headings that are full matches:
United States. Congress. House. Committee on Appropriations: United States United States - Congress United States - Congress - House United States - Congress - House - Committee on Appropriations
The above example generates 4 authority record matches that are returned to the library if all levels of hierarchy is selected.
If full heading strings only is selected, MARS 2.0 distributes the one full authority: United States - Congress - House - Committee on Appropriations
Name/title compound heading
An additional example of the importance of receiving authority records for all levels of hierarchy is a name/title compound heading:
original bib heading: $a James, Henry, $d 1843-1916. $t Short stories. $k Selections MARS 2.0 distributes both authority records below, only if all levels of hierarchy is selected: $a James, Henry, $d 1843-1916. $a James, Henry, $d 1843-1916. $t Short stories. $k Selections
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