DiscoverEd Metadata
Overview
This document outlines some of the metadata ccLearn is utilizing for the Universal Education Search project. This metadata is collected from syndicated feeds (RSS, Atom), OAI-PMH aggregations and crawls (embedded RDFa). While the metadata store may include additional information from resources, these fields are exposed by default in the search results.
ccLearn's Universal Education Search will be indexing RDFa when pages are crawled, making this our preferred way of encoding machine readable metadata. We believe this will have the broadest possible exposure for current and future software agents.
- Title (
DCT:title
): A brief descriptive title for the resource. - Summary (
DCT:description
): A relatively short summary or synopsis of the resource. - License (
DCT:license
,cc:license
,xhtml:license
): The URL of the work's license; e.g.,http://creativecommons.org/licenses/by/3.0/
. - Education level (
DCT:educationLevel
): What grade(s) or age-level(s) this material is suitable for. - Language (
xml:lang
,DCT:language
): The language(s) of the referenced resource (not of your site). - Subject (
DCT:subject
): The subject(s) of the resource; e.g., math.
Contents
Vocabulary
Specifying Subject
The subject refers to the actual content in the resource; i.e., what is this resource about? For many resources, more than one subject will be necessary; in this case, specify multiple subject elements. We ask that you try to limit the contents of the subject to only those subjects that are objectively reflective of the entire resource. Other types of categories (opinions, metrics, etc) may have other vocabularies available which are more appropriate.
Specifying Education level
The education level should indicate all levels (student ages) for which the resource is deemed appropriate. The education level should be labeled using the DCT:educationLevel term.
Though we will accept any descriptions that seem appropriate to you, please consider using one of the following schemas:
- primary, secondary, tertiary, adult;
- K,1,2,3,...,20 (where the number refers to the actual grade-level).
You may include equivalent terms as well by specifying more than one DCT:educationLevel
<category>. For example, you might include a DCT:educationLevel
for 9
, 10
, and secondary
.
Specifying Language
When specifying the language for a resource, the value should be specified as described by RFC-4646. For example, en
for English. To distinguish English (United States) from English (United Kindgom), the language would be specified as en-US
and en-GB
, respectively.
In an Atom 1.0 feed, the language is specified as the xml:lang
attribute of the content
element. Multiple languages in a single entry is not supported.
Embedding license data
Since the licensing of a resource is expected to be conveyed via URL, we can leverage the Atom <link> element. However we must markup the link element so as to identify it as a license URL. This is accomplished with adding the attribute rel="license" to the <link> element. For example:
<link rel="license" href="http://creativecommons.org/licenses/by/3.0/" />
See the complete CC with syndication formats documentation for more information.
Examples
Atom 1.0 Example
Here is a sample, one entry Atom 1.0 feed which implements the guidelines above.
<feed xmlns="http://www.w3.org/2005/Atom"> <id>http://oersite.org/cc/</id> <title>OER Aggregation Web Site</title> <updated>2008-01-16T12:00:00Z</updated> <link rel="self" href="http://oersite.org/cc/atom.xml" type="application/atom+xml" /> <author> <name>John Q. Public</name> <email>webmaster@oersite.org</email> </author> <entry> <id>tag:ocw.org,2007-10-15:/math/101</id> <updated>2007-10-15T12:00:00Z</updated> <link href="http://ocw.org/math/101" /> <title>Math 101</title> <summary>Basic mathematics for 5th graders</summary> <link rel="license" href="http://creativecommons.org/licenses/by/3.0/" /> <category term="cc:subject:Math" /> <category term="dc:educationLevel:5" /> <content type="xhtml" xml:lang="en">The content</content> </entry> </feed>