This is of no surprise to me as the social media companies are interested in currency not the past. Neither do their business models encourage archiving of user content no matter how trivial it would seem to be to implement (according to some of those commenting on this article).
They found that the older the social media, the more likely its content was to be missing. In fact, they found an almost linear relationship between time and the percentage lost.
The numbers are startling. They say that 11 per cent of the social media content had disappeared within a year and 27 per cent within 2 years. Beyond that, SalahEldeen and Nelson say the world loses 0.02 per cent of its culturally significant social media material every day.
The study is here:
Losing My Revolution: How Many Resources Shared on Social Media Have Been Lost?
Library of Congress to develop Medium of Performance Thesaurus for Music in cooperation with the Music Library Association
The Library of Congress, in cooperation with the Music Library Association, has begun to develop a new thesaurus of terms representing vocabulary for the medium of performance of musical works. The vocabulary is intended to be used, at least initially, for two bibliographic purposes:
- to retrieve music by its medium of performance in library catalogs, as is now done by the controlled vocabulary, Library of Congress Subject Headings (LCSH);
- to record the element “medium of performance” of musical works, as represented in individual music resources cataloged according to RDA: Resource Description and Access (RDA).
Medium of Performance for Music: Working List of Terminology
An update of the list, Medium of Performance for Music: Working List of Terminology [PDF, 934 KB], has been posted, including new and modified relevant headings from the weekly or monthly additions and changes to Library of Congress Subject Headings (LCSH).
One of seven types of items for which the MARC 21 format for bibliographic description establishes content designators for data elements. The category includesprinted, manuscript, and microform music, as well as musical and nonmusical sound recordings. Music materials may be monographic or serial. The code MU is often used in written MARC documentation to designate this material type.
– from Online Dictionary for Library and Information Science (ODLIS) by Joan M. Reitz http://www.abc-clio.com/ODLIS/odlis_m.aspx#music