The IMS Reusable Definition of Competencies or
Educational Objective (IMS RDCEO, 2002) and the
later IEEE Reusable Competency Definition (IEEE
RCD, 2005) (based on IMS RDCEO) focus on
reusable competency definitions. The primary idea is
to build central repositories which define competen-
cies for certain communities. These definitions can
be referenced by external data structures, encouraging
interoperability and reusability. However, IEEE RCD
lacks information on context and proficiencylevel and
does not allow relationships or recursive dependen-
cies among competencies.
HR-XML focuses on the modeling of a wide range
of information related to human resource tasks (like
contact data or aspects of the curriculum vitae). The
work performed in HR-XML Measurable Competen-
cies (HR-XML, 2004) tries to define profiles in order
to use such competency definitions. It specifies data
sets like job requirement profiles (which describe the
competencies that a person is required to have) or per-
sonal competency profiles (which describe the com-
petencies a person has). Such profiles are composed
of evidences (either required or acquired) referring to
competency definitions (e.g., IEEE RCD). Unfortu-
nately, the proposed model does not clearly separate
required and acquired profiles. The consequence is
that an acquired competency could have mandatory
and optional elements according to the model. Fur-
thermore, it is unclear why a competencyis composed
of several evidences: since a competency is a reusable
object, evidences should rather represent a require-
ment or demonstrate the acquirance of a competency.
Hence, the evidences should refer to or contain com-
petency definitions and not vice versa.
The Simple Reusable Competency Map (SRCM,
2006) tries to model relationships between competen-
cies. A map can contain information about depen-
dencies/equivalences among competencies, including
the composition of complex competencies from sim-
pler ones. In SRCM, relationships are modeled us-
ing a directed acyclic graph. However, the semantics
of the model proposed in SRCM is confusing. Re-
lationships among different nodes may have different
meanings: composition, equivalence or order depen-
dency. This leads to confusion when modeling tasks
as well as when creating algorithms to use such in-
formation. Furthermore, combination and weighting
of competencies is not clearly defined, and external
references to the maps (e.g., from profiles) must point
to the root (and not to any node), therefore requiring
the traversal of the graph until the appropriate node
is found. Moreover, in this paper we argue that it is
not possible to model relationships among competen-
cies, because proficiency level and context have to be
considered. For example, statistics knowledge may
be a requisite for becoming a computer scientist or a
sociologist. However, the proficiency level required
and the context in which the competency is applied
are completely different, hence making impossible to
create relationships directly among competencies.
In OntoProPer (Sure et al., 2000), profiles are
described by flat vectors containing weighted skills
(where weights grow from 0 to 3), which are ex-
pressed as labels. Weights represent importance if ap-
plied to requirements or skill level if applied to ac-
quired skills. The system itself mainly focuses on
profile matching and introduces an automated way
of building and maintaining profiles based on ontolo-
gies. (Colucci et al., 2003) describes an ontology-
based semantic matchmaking(using Description Log-
ics) between skills demand and supply. In (Lefebvre
et al., 2005), which also defines a competence on-
tology for domain knowledge dissemination and re-
trieval, a competence is related to capabilities, skills
and expertise (measured by levels growing from 1 to
5). Although this approach is closer to our definition
of competence, still the context is not tackled, the re-
lationships are defined at the skill level and the profi-
ciency levels are not flexible enough.
4 MODELLING A COMPETENCE
In this section we introduce a model for representing a
competence with a broader and clearly defined view.
We base this model on the three dimensions that a
competence is composed of: competency, proficiency
level and context. We first describe each dimension
separately and finally present how they are combined
in order to build a competence and how competences
may be composed of sub-competences. Several issues
encountered during the modeling process, and possi-
ble solutions (eventually with a trade-off between ex-
pressiveness and complexity) are described. We also
discuss the decisions we have taken as well as their
features and the limitations derived from them.
4.1 Competency
The IEEE Reusable Competency Definitions (IEEE
RCD, 2005) provide a model for the representation of
competencies (figure 2). The model does not include
proficiency level or context information. In addition,
as stated in the specification, IEEE RCD is “intended
to meet the simple need of referencing and cataloging
a competency, not classifying it”, that is, it does not
provide any means to specify relationships between
competencies. We agree upon this view and believe
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