IEEE Learning Object Metadata

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IEEE Learning Object Metadata

• Implications for Preservation and Digital Curation

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(Very) Brief History of IEEE LOM

• International standard produced by IEEE Learning
  Technology Standards Committee.
• Built on work undertaken by
• US IMS Project (now IMS Global Learning
  Consortium).
• EU ARIADNE Project (now ARIADNE Initiative).
• Dublin Core Metadata Initiative.

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IEEE LOM

• Multipart standard composed of
• 1484.12.1-2002 IEEE Standard for Learning Object
  Metadata.
• 1484.12.3-2005 IEEE Learning Technology Standard
  - Extensible Markup Language (XML) Schema
  Definition Language Binding for Learning Object
  Metadata.

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Purpose of the LOM

• to facilitate search, evaluation, acquisition
  and use of learning objects, for instance by
  learners or instructors or automated software
  processes. This multi-part standard also
  facilitates the sharing and exchange of learning
  objects , by enabling the development of catalogs
  and inventories while taking into account the
  diversity of cultural and lingual contexts in
  which the learning objects and their metadata are
  reused.

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A definition of a learning object

• For this standard, a learning object is defined
  as any entity - digital or non digital - that
  may be used for learning, education or training.

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A definition of a learning object

• For this standard, a learning object is defined
  as any entity - digital or non digital - that
  may be used for learning, education or training.

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A definition of a learning object

• For this standard, a learning object is defined
  as any entity - digital or non digital - that
  may be used for learning, education or training.
• Sidesteps discussion of what distinguishes an
  educational resource from other types of
  resources.

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Preservation issue 1

• LOM metadata may legitimately be applied to
  resources that are not designed specifically for
  use in an educational context.

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Preservation issue 2

• IEEE LOM may legitimately be used to describe
  many different characteristics of any kind of
  resource used in an educational context.

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LOM categories

• General
• Lifecycle
• Meta-metadata
• Technical
• Educational
• Rights
• Relation
• Annotation
• Classification

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Structure of the LOM data schema

• LOM conceptual data schema is hierarchical.
• Schema is a tree composed of categories,
  aggregate elements, simple elements, datatypes
  and value spaces.

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Structure and semantics

• Each simple data element derives its context and
  its semantics from the categories and aggregate
  elements its contained by.

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Preservation issue 3

• If a simple element is abstracted from the
  hierarchy of container elements that describe its
  semantics its impossible to know what
  characteristic is being described.
• Also very difficult to combine or cross walk LOM
  with flat Dublin Core metadata.

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Smallest permitted maximum

• LOM defines smallest permitted maximum values for
  aggregate elements and data elements with the
  datatype CharacterString or LangString.
• Refers to the minimum number of instances of an
  element or characters in a string that an
  application shall process.

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Preservation issue 4

• If a metadata instance includes more than the
  smallest permitted maximum number of occurrences
  of a particular element there is no guarantee
  that all these occurrences will be processed.
• As repeated occurrences of some elements are
  ordered and others are unordered it is difficult
  to predict what information may be lost.
• Same applies to CharacterStrings and LangStrings
  which may be cut short.

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Conformance

• LOM conceptual data schema defines conformance as
  follows
• A strictly conforming LOM metadata instance shall
  consist solely of LOM data elements.
• A conforming LOM metadata instance may contain
  extended data elements.
• A LOM instance that contains no value for any of
  the LOM data elements is a conforming instance.
• All data elements are optional. This means that
  a conforming LOM instance may include values for
  any data element defined in Clause 6.

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Preservation issue 5

• Applications have no way of knowing which
  elements a LOM instance may be composed of.
• The LOM has no minimum core element set.

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Extending the LOM

• LOM conceptual data schema may be extended by
• Adding new vocabularies to existing elements
• Adding new elements.
• Current recommended practice is to use Category 9
  Classification elements to accommodate
  extensions.
• By adding new terms to Classification. Purpose
  vocabulary and identifying classification schemes
  to describe these terms can accommodate
  characteristics not be covered elsewhere.

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Preservation issue 6

• All extensions have an impact on
  interoperability, curation and preservation.
• Community specific extensions may not be
  processed by applications outwith their immediate
  domain and this information may be lost.

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Preservation issue 7

• In the rapidly evolving domain of e-learning
  practitioners often feel the need to develop new
  vocabularies.
• These may lack the maintenance strategies that
  accompany more established classification
  schemes.
• Consequently these vocabularies may be difficult
  to preserve.

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Application profiles

• Implementations of the LOM are normally based on
  application profiles.
• The purpose of an application profile is to
  adapt or combine existing schemas into a package
  that is tailored to the functional requirements
  of a particular application, while retaining
  interoperability with the original base schemas.
  (Duval et al, 2002).

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LOM application profiles

• LOM profiles tend to be based on the LOM schema
  alone.
• They may
• Restrict element usage.
• Designate elements as being mandatory or
  optional.
• Specify vocabulary usage and classification
  schemes.
• Constrain data model by dictating how elements
  are used and repeated.

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Preservation issue 8

• Preservation of application profiles is likely to
  be problematic unless they are developed in some
  kind of standard format and recorded in a schema
  registry.
• Few registries exist that can accommodate
  hierarchical LOM application profiles.
• See JISC IEMSR for further details
• http//www.ukoln.ac.uk/projects/iemsr/

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IEEE LOM and IMS Content Packaging

• Learning objects and their metadata are
  frequently aggregated in IMS Content Packages.
• IMS CP is designed to handle complex objects with
  considerable flexibility.
• Metadata can be added to almost any component of
  the package.
• Metadata may be internal or referenced.

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Preservation issue 9

• Applications may fail to process packages
  depending on the placement of metadata within the
  package.
• Links to external metadata may break.
• IMS is revising CP spec to clarify known
  ambiguities and provide clearer guidelines on
  metadata location and handling.

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Support for LOM implementers

• CETIS Metadata and Digital Repositories Special
  Interest Group
• http//metadata.cetis.ac.uk/
• http//www.jiscmail.ac.uk/lists/cetis-metadata.htm
  l
• Facilitated by Phil Barker
• philb_at_icbl.hw.ac.uk