The neighbouring entities are grouped
according to their relation type (described in
Definition 1). We have also added an option to
include keywords that typically represent the
ontology as a whole. Larger ontologies tend to
include several minor domains. E.g., the Wine
ontology used in the experiments includes the
Food ontology. A user, using this ontology and
searching using the 'Lobster' entity, would expect
to get lobster in relation to wine results since
'Lobster' is part of the Wine domain (ontology).
Therefore, using keywords will create FVs that are
more homogeneous and hence can be beneficial
when creating FVs that are more true to the
domain defined by the ontology as a whole
(Gligorov et al., 2007). Omitting keywords would
create FVs that are more unique and hence truer to
the local variances in the ontology and not
necessarily to the ontology as a whole.