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Descriptions and modes of access for resource discovery-related metadata

Purpose of Guide

The Yale University Library (“the Library”) assigns structured metadata to describe our collections and make them discoverable through local catalogs and search engines such as Quicksearch, Archives at Yale, and Yale Digital Collections.
As much care as we put into our local discovery tools -- and we certainly encourage you to use them -- we recognize that the best uses of our data may come from those who remix and re-publish these data in novel and interesting ways. We therefore welcome efforts to devise new ways of exploring and accessing our collections and classification systems, including building one’s own discovery tools and services.
Toward this end, we release our metadata as openly and widely as possible. We avoid placing restrictions on reuse, except in cases of ethical, contractual or legal obligations, e.g., metadata received on condition that we not share them further, or metadata for which sharing might compromise user privacy. This service is in line with Yale’s broader support for open access, including the high resolution digital images made available through our cross-collection discovery portal, and open scholarly communication enabled through our EliScholar platform.
Most metadata generated by the Library will be open, by default, for sharing and reuse, and released with a public domain Creative Commons CCO license. Records derived from the shared OCLC WorldCat database are made available as Open Data Commons ODC-BY with a credit to OCLC. In all other cases, we will attempt to negotiate terms that allow maximal sharing and reuse, as we do with our locally produced records, and label them accordingly.


Modes of Access

The Library intends to make it as easy as possible to download or query our data, both by human agents and machines. Below, we provide brief descriptions and access options for currently available datasets. These are followed by datasets under current review, followed by datasets of possible interest for the future.

Datasets currently available   

Bibliographic datasets

  • Orbis (Yale catalog) bibliographic, holdings, items, and authority records  
    • Bulk MARC downloads.  Files are updated daily and refreshed every Sunday. The output includes bibliographic, holdings, and item data. 
      • Where appropriate, we embed sharing rights directly into the records themselves, e.g.:
        • "500  \\$aThis WorldCat-derived record is shareable under Open Data Commons ODC-BY, with attribution to OCLC.$5CTY"
        • "500  \\$aThis Yale-originated record is shareable under Creative Commons license CC0.$5CTY"
      • MARC authority records, included if they correspond to access points in the bibliographic files, are shared as public domain resource by the Library of Congress.
      • Note the following file-naming conventions, where 'type' is either 'aut' or 'bib', yyyymmdd is the run date, 'run' values can be 'full' or 'incr,' and 'nnn' is the file sequence number. Here are the standard file types:
        • bib_yyyymmdd_run.txt: bibliographic record identifier list  
        • type_yyyymmdd_run: directory containing output MARC record files, 
        • type_yyyymmdd_run_nnn.mrc: output MARC record files
        • mrc_yyyymmdd_run.tsv: output file and record inventory
        • type_yyyymmdd_del.txt: record identifiers to be deleted when running an update
    • Z39.50 protocol​ (MARC, XML, OAI-PMH; updated dynamically)
    • BIBFRAME XML bulk downloads. Sharing is permitted. (updated when new records sets are available via SHARE-VDE)

Archival datasets

Encoded Archival Description (EAD) files are shared according to the CC0 1.0 Universal license

Datasets under consideration or review 

  • Orbis bibliographic records 
  • Morris (Law Library catalog) 
    • MARC bulk downloads

Datasets of possible future interest

  • Archives at Yale (API access)
  • Audio-visual collections metadata (Avalon Media Systems)
  • ContentDM (e.g. Yale Daily News Archive)
  • EliScholar (local instance of BePress Digital Commons)
  • Digital Collections (FindIT)  
  • MORRIS (Law Library Catalog API access)
  • Yale University web archives

Modes of Access