PPLRE Research Topics - Ternary Relations

Synopsis: Recent research has focused on unary relationships and on binary relationships such as Composer(C) and OrgHeadquarterLocation(O,L). N-ary Relations however are commonplace, for example Event Relations typically unite two Concepts with a Temporal Relation. The PPLRE task also happens to be a ternary relation, OPL(). And although it can be divided into two binary relations, a unified approach would have access to more information. Ideas for identifying N-ary Relations in one step is to identify patterns in a Text Graph.

Evidence

Currently we ourselves have broken the task down into a search for the two binary relationships of OP() and PL().
There are examples (below) where one ternary pattern appears to be simpler to acquire than two binary patterns.

PPLRE Corpus 80.a.0: Cytochrome c3(PROTEIN), a small (14-kDa) soluble tetraheme protein was isolated from the periplasmic fraction(LOCATION) of Desulfovibrio desulfuricans(ORGANISM) strain Essex 6.

A ternary Dependency Grammar Pattern could be:
- PROTEIN <=(nsubjpass)<=isolated=>(prep_from) =>LOCATION=>prep_of=>ORGANISM.
- Notice that the path between the organism and the protein involves the location. Therefore this pattern could extract the ternary relation at once.