Slides for the 12th Extended Semantic Web Conference

1. FrameBase: Representing N-ary Relations
Using Semantic Frames
Jacobo Rouces
Aalborg University
jrg@es.aau.dk
Gerard de Melo
Tsinghua University
gdm@demelo.org
Katja Hose
Aalborg University
khose@cs.aau.dk

2. Jacobo Rouces, Gerard De Melo, Katja Hose
02/06/15 2
Ways to represent N-ary relations.
● Using Direct Binary Relations
– Used by “default” in most KBs. Dereified.
● RDF reification
– YAGO,YAGO2s
● Subproperties
– Proposed in [Nguyen et al, WWW 2014]
● Neo-davidsonian representations
– To an extent used in most Kbs that include events.
Freebase, Framebase

3. Jacobo Rouces, Gerard De Melo, Katja Hose
02/06/15 3
Ways to represent N-ary relations
Direct Binary Relations
● Pairwise properties around an event (unreified)
✗ From N up to N(N-1) triples:
person1 gotMarriedWith person2
person1 gotMarriedInPlace place
person2 gotMarriedInPlace place
person1 gotMarriedOnDate time
person2 gotMarriedOnDate time
person1 ceremonyType marriageCeremonyType
person2 ceremonyType marriageCeremonyType
place holdWeddingOnDate time
✗ Without events, connections are unknown:
Sarkozy gotMarriedWith Carla_Bruni
Sarkozy gotMarriedWith Cécilia_Attias
Sarkozy gotMarriedOnDate 2007
Sarkozy gotMarriedOnDate 1996
?

4. Jacobo Rouces, Gerard De Melo, Katja Hose
02/06/15 4
e1 e2
e3
Ways to represent N-ary relations.
Direct Binary Relations
e1 p e2 .
e2 q e3 .
e3 r e4 .

5. Jacobo Rouces, Gerard De Melo, Katja Hose
02/06/15 5
Ways to represent N-ary relations
RDF reification
e1
Statement
e2
● Original triple
e1 p e2
● Reified with additional triples. r signifies the triple:
r rdf:type rdf:Statement
r rdf:subject e1
r rdf:property p
r rdf:object e2
– RDF reification is different from (general) reification, where the new entity r
would signify, not a triple but the event or frame evoked by a property.
● This other kind is central to FrameBase, and will come later.

6. Jacobo Rouces, Gerard De Melo, Katja Hose
02/06/15 6
Ways to represent N-ary relations
RDF reification
e1 e2
e3

7. Jacobo Rouces, Gerard De Melo, Katja Hose
02/06/15 7
Ways to represent N-ary relations
RDF reification
e1
Statement
e2
e3
Statement
Statement

8. Jacobo Rouces, Gerard De Melo, Katja Hose
02/06/15 8
Ways to represent N-ary relations
RDF reification
● Possible third way: reifying a primary triple (YAGO). But:
✗ 4-fold overhead when using pure RDF, or need for quads.
Lower triplestore performance and cumbersome queries.
✗ The advantage (including also the direct binary relation) is only for the
primary pair. For the other direct binary relations, more reifications are
needed.
✗ Which one is the primary pair? Can the user replicate the choice?
✗ Mixing metadata with data leads to ambiguity and errors in LOD:
Something like “:factId :time 2013” would mean that Einstein won the
Nobel Prize in the 21st
century or that the triple was created at that time?
✗ Non-unique triple ids when several instances of the event share the
primary pair.

9. Jacobo Rouces, Gerard De Melo, Katja Hose
02/06/15 9
Ways to represent N-ary relations
Neo-Davidsonian representation
● Reified properties (connecting properties around an event).
✔ N+1 triples:
event type marriage
event partner Sarkozy
event partner Carla_Bruni
event time 2007
event location Paris
event manner civilCeremony
✔ Unlike the case with direct binary predicates, events can be
separated
event2 type Marriage
event2 partner1 Sarkozy
event2 partner2 Cécilia_Attias
event2 time 1996
A.k.a. Neo-Davidsonian representation

10. Jacobo Rouces, Gerard De Melo, Katja Hose
02/06/15 10
Ways to represent N-ary relations
Neo-Davidsonian representation
● Example from http://purl.org/vocab/bio/0.1/Marriage
_:e a bio:Marriage
; dc:date "1903"
; bio:partner dbpedia:Albert_Einstein
; bio:partner dbpedia:Mileva_Mari%C4%87
; bio:place dbpedia:Bern
.

11. Jacobo Rouces, Gerard De Melo, Katja Hose
02/06/15 11
Ways to represent N-ary relations
Neo-Davidsonian representation
e1
Event type
e2
e3

12. Jacobo Rouces, Gerard De Melo, Katja Hose
02/06/15 12
Ways to represent N-ary relations
● Using different representations is troublesome:
✗ Low recall when querying
● The user may use a different schema to model the query
✗ Alignment hindered
● Ontology alignment systems usually search direct
equivalences between classes, properties, etc.

13. Jacobo Rouces, Gerard De Melo, Katja Hose
02/06/15 13
FrameBase
● Core: RDFS schema to represent knowledge using neo-
Davidsonian approach with a wide and extensible vocabulary of
– frames (events, situations, frames, eventualities…)
– frame elements (outgoing properties representing frame-specific
semantic roles)
● Vocabulary based on NLP resources (FrameNet+WordNet)
– This provides connection with natural language and semantic role labeling
systems.
● Inference rules to provide direct binary predicates
?f a :frame-Separating-partition.v
?f :fe-Separating-Whole ?s ?s :isPartitionedIntoParts ?o
?f :fe-Separating-Parts ?o
We will explain these points now...

14. Jacobo Rouces, Gerard De Melo, Katja Hose
02/06/15 14
FrameBase:
Core schema
e1
Frame type
e2
e3
FRAME CLASS
FRAME ELEMENT
(FRAME-SPECIFIC
SEMANTIC ROLES)
FRAME INSTANCE

15. Jacobo Rouces, Gerard De Melo, Katja Hose
02/06/15 15
FrameBase:
Core schema
● Problems using FrameNet:
✗ Coverage is limited
✗ Some frames and FEs are too general
☞ Create micro-frames with LUs
✗ Too many near-equivalent frames now! Sparsity.
☞We must cluster near-equivalent senses
by aligning and extending with WordNet (algorithm in the paper)
● Using synsets and lexical-semantic pointers we group
● Synonyms
● Near-equivalent senses
● Morphosemantic variations. e.g nominalizations

16. Jacobo Rouces, Gerard De Melo, Katja Hose
02/06/15 16
FrameBase:
Core schema
..defect.v
..defection.n
..desert.v
..desertion.n
..desertion_n_00055315
..defect_v_02584097
..abandon_v_00614057
..deserter_n_10007109
..deserter_n_10006842
..retreat.v
..withdraw.v
..withdrawal.n
..receding_n_00057486
..pullback_n_00056688
..withdraw_v_01994442
..withdrawal_n_00053913
:frame-Quitting_a_place
deserter
turncoat
apostate
ratter
recreant
renegade
desertion
abandonment
defection
deserter
defector
defect
desert
abandon
desert
desolate
forsake
pullback
receding
recession
withdraw
retire
retreat
draw
back
pull
back
move
back
recede
pull
away
withdrawal

17. Jacobo Rouces, Gerard De Melo, Katja Hose
02/06/15 17
FrameBase:
Core schema
..defect.v
..defection.n
..desert.v
..desertion.n
..desertion_n_00055315
..defect_v_02584097
..abandon_v_00614057
..deserter_n_10007109
..deserter_n_10006842
..retreat.v
..withdraw.v
..withdrawal.n
..receding_n_00057486
..pullback_n_00056688
..withdraw_v_01994442
..withdrawal_n_00053913
:frame-Quitting_a_place
deserter
turncoat
apostate
ratter
recreant
renegade
desertion
abandonment
defection
deserter
defector
defect
desert
abandon
desert
desolate
forsake
pullback
receding
recession
withdraw
retire
retreat
draw
back
pull
back
move
back
recede
pull
away
withdrawal

18. Jacobo Rouces, Gerard De Melo, Katja Hose
02/06/15 18
FrameBase:
Reification-dereification rules
● Challenge using neo-davidsonian representation: The
reification provided by frames is necessary when more
than two slots/arguments are filled, but sometimes is not.
✗ Overhead querying and storing.

19. Jacobo Rouces, Gerard De Melo, Katja Hose
02/06/15 19
FrameBase:
Reification-dereification rules
☞ Solution in FrameBase: Two-layered structure.
– Create two levels of reification, and inference rules that
connect them.
● Reified knowledge using frames and frame elements
● Dereified knowledge using direct binary predicates
– Rules are definite clauses (easy for inference engines)
e1
Event type
e2
e3
?f a :frame-Separating-partition.v
AND
?f :fe-Separating-Whole ?s
AND
?f :fe-Separating-Parts ?o
IFF
?s ..-isPartitionedIntoParts ?o

20. Jacobo Rouces, Gerard De Melo, Katja Hose
02/06/15 20
Example: Win_prize frame
:frame-Win_prize-win.v
...-competitor
yago:A_Einsteinyago:Nobel_Prize
fe-Win_prize-competition
fe-Win_prize-prize
1921^xsd:date
...-time ...-explanation
BEYOND TIME
AND LOCATION!

21. Jacobo Rouces, Gerard De Melo, Katja Hose
02/06/15 21
Example: Win_prize frame
:frame-Win_prize-win.v
...-competitor
yago:A_Einsteinyago:Nobel_Prize
fe-Win_prize-competition
fe-Win_prize-prize
1921^xsd:date
...-time
yago:Photoelectric_effect
...-explanation
frame:Working_on-work.n
fe-Working_on-agent
...-domain
...-time
1905^xsd:date
BEYOND TIME
AND LOCATION!

22. Jacobo Rouces, Gerard De Melo, Katja Hose
02/06/15 22
Example: Win_prize frame
:frame-Win_prize-win.v
...-competitor
yago:A_Einsteinyago:Nobel_Prize
fe-Win_prize-competition
fe-Win_prize-prize
1921^xsd:date
...-time
?
?
?
yago:Photoelectric_effect
...-explanation
frame:Working_on-work.n
fe-Working_on-agent
...-domain
...-time
1905^xsd:date
?
BEYOND TIME
AND LOCATION!

23. Jacobo Rouces, Gerard De Melo, Katja Hose
02/06/15 23
Example: Win_prize frame
:frame-Win_prize-win.v
...-competitor
yago:A_Einsteinyago:Nobel_Prize
fe-Win_prize-competition
fe-Win_prize-prize
1921^xsd:date
...-time
winsByCompetitor
winsAtTime
isWonAtTime
yago:Photoelectric_effect
...-explanation
frame:Working_on-work.n
fe-Working_on-agent
...-domain
...-time
1905^xsd:date
worksAtTime
BEYOND TIME
AND LOCATION!

24. Jacobo Rouces, Gerard De Melo, Katja Hose
02/06/15 24
FrameBase:
Reification-dereification rules
● FrameBase: Two-layered structure:
☞Create two levels of reification, and inference rules that
connect them.
● Reified knowledge using frames and frame elements
● Dereified knowledge using direct binary predicates
– Rules are Horn clauses (good for inference engines)
– Around 15000 rules and
direct binary predicates are
created automatically.
– Different storage strategies
are possible.
?f a :frame-Separating-partition.v
AND
?f :fe-Separating-Whole ?s
AND
?f :fe-Separating-Parts ?o
IFF
?s ..-isPartitionedIntoParts ?o

25. Jacobo Rouces, Gerard De Melo, Katja Hose
02/06/15 25
FrameBase:
Integration rules
● Integration rules from source KBs can be created with
SPARQL CONSTRUCT queries (and optionally a RDFier)
CONSTRUCT {
_:e a framebase:frame-People_by_jurisdiction-citizen.n .
_:e framebase:fe-People_by_jurisdiction-Person ?person .
_:e framebase:fe-People_by_jurisdiction-Jurisdiction ?country .
} WHERE {
?person freebase:people.person.nationality ?country .
}
● More examples in the DeRiVE 2015 paper “Representing
Specialized Events with FrameBase”

26. Jacobo Rouces, Gerard De Melo, Katja Hose
02/06/15 26
Results
● RDFS schema of size 250,407 triples
– Using FrameNet-WordNet mapping with precision = 0.789
– It provides 19,376 frames with lexical labels
● A total of 18,357 microframes
– 11,939 LU-microframes
– 6,418 synset-microframes.
– Grouped into 8,145 logical clusters:
● sets of microframes whose elements are linked by a
logical near-equivalence relation.
● We generate automatically 14,930 reification–dereification
rules for the same number of direct binary predicates.
– Human-readable
– 86.59% ± 6.41% were correct.

27. Jacobo Rouces, Gerard De Melo, Katja Hose
02/06/15 27
Data
● More information: http://framebase.org
● Data is open-source.
– License: CC-BY 4.0 International
– Everybody is welcome to publish their
data using the FrameBase schema!
The research leading to these results has received funding from the European Union
Seventh Framework Programme (FP7/2007-2013) under grant agreement No. FP7-
SEC-2012-312651 (ePOOLICE project).
Additional funding was provided by National Basic Research Program of China Grants
2011CBA00300, 2011CBA00301, and NSFC Grants 61033001, 61361136003.

28. Jacobo Rouces, Gerard De Melo, Katja Hose
02/06/15 28
Conclusion
● FrameBase offers a reusable, wide-range, semantically
rich, natural-language-related and extensible schema for
representation of n-ary relations, events, situations,
processes, natural kinds, etc. (in general: frames).
● Two levels of representation: reified and dereified.
● Future work:
– Automatic integration of source KBs
– Interfacing with NL and QA (SEMAFOR).

29. Jacobo Rouces, Gerard De Melo, Katja Hose
02/06/15 29