Following up on the previous post about the ISO/IEC 19788-1:2011, I will be discussing some parts of the document at hand, simplifying some definitions. I hope that this will provide a handy overview of the standard and that it will also help people that are looking to get a quick overview before going into more technical details. For those, I encourage you to get your hands on the actual standard and look for more information. To refresh your memory a bit, I will paste here a concept map of my own, on the basic “concepts” of MLR.
Going back to the framework (it is available for download), in page 7, we read that a Data Element Specification (DES) defines the attributes and values of the Data Element and also the rules that govern those values. So in a Data Element Specification we will find the following attributes (refer to the document for more detailed presentation of the following):
- Identifier: This is a unique reference tag used to identify the DES across systems and platforms. They are language independent, technology-independent and as self-explanatory as possible.
- Property name: This is the data element name that has to be unique within the ISO/IEC 19788 standard and that can also have multiple equivalent names in different languages (translations).
- Definition: This is actually the description of a data element. Multiple descriptions (definitions) in various languages may apply here.
- Linguistic Indicator: This attribute specifies whether or not the content value of the data elements described by the specification is linguistically neutral.
- Domain: Indicates the resources that this data element specification can be used to describe. The value of this attribute is an identifier that links to the specific resource class (it can be all the learning objects for example, or just a subset).
- Range: It specifies the range of data elements that obey this specification. The value can either be a resource class or specific strings representing values (literals).
- Content value rules: When the range (above) of a data element is represented by a literal, this attribute gets a rule set as a value.
- Refines: With the use of this attribute we can indicate if the data element described by this specification is a refinement of another data element described by a different specification.
- Example(s): This attribute is used to provide examples of conformant data elements. It’s meant to provide examples of use so that the user can understand what kind of values are expected in this data element.
- Note(s): This attribute is used simply to provide comments, explanatory information or remarks about a data element.
The information above may be a bit confusing especially for some attributes, so it would be best to look for the specific example in page 12 of the standard. Looking at the specific data elements within the data elements specification, are entities of 3 or 4 parts, following on of the two formats:
<dataElementSpecificationID, subject, contentValue>
<dataElementSpecificationID, subject, contentValue, languageCode>
- dataElementSpecificationID = Identifier of a data element specification
- subject = the resource being described (denoted by an Identifier)
- contentValue = the actual information recorded as the content of the data element (belongs to its range)
- languageCode = represents the language used in the contentValue
The document continues by defining the syntax for the description of a Resource Class. A Resource Class has (a) an identifier, (b) a name, (c) a definition, (d) a relation (SubclassOf) and (e) a Note. The interesting thing here is that also people can be defined as a Resource Class, which is quite different from the IEEE LOM approach of a vCard. In the next section, the representation of rule sets is explained, providing simple examples of how Duration, Date and Date & Time are expressed.
To continue, it’s interesting to look at how a Metadata Learning Resource (MLR) record is structured. An MLR record is a specified set of data elements that are used to describe a learning resource and resources related to it. An MLR record can include data elements from any part of ISO/IEC 19788 but also data elements defined by other authorities or communities. Each MLR record contains (a) an identifier for the record itself, (b) an identifier pointing the learning resource being described and (c) a set of data elements that describe the learning resource and associated resources.
As far as data element groups are concerned, they can be used to group some elements as a logical entity. Despite the fact that data elements may be a part of one or more specifications, sometimes it’s easier and useful to group them through data element groups. Each Data Element Group Specification has the following attributes: (a) identifier, (b) name and (c) description.
Approaching the specification of application profiles, it is made clear that within a specific application profile, someone can force normally optional data elements as mandatory and extend or restrict existing vocabularies. In this way, ISO/IEC 19788 allows for a variety of user extensions. The information that are needed to describe an application profile are (a) identifier of the application profile and underlying data element group specification, (b) name of the application profile and (c) description of the purpose of the application profile. The rules that govern the creation of application profiles seem really straightforward and the details offered about the possibility of limiting or extending vocabularies and the presence or repeatability of the data elements are also clear.
The concept maps in the end of the document provide a nice overview that is useful once you complete a couple of “passes” through the document. I am still trying to digest come concepts and the logic behind the standard. It seems to make perfect sense but in order to be able to utilize and implement it, you need to really ingest it. I am currently trying to get access to the other parts of the ISO/IEC 19788, with no luck so far, to check out how the other parts are structured. I would be more than obliged if you have any material you can share! 😉