A GRAPHICAL SCHEME FOR COMPLEX
KNOWLEDGE REPRESENTATION
Chandra S. Amaravadi
Western Illinois University
Macomb, IL
ATSIR, Taipei, Taiwan
November 22-24, 2013
1
Overview
Introduction
Relevant literature
Characteristics of complex knowledge
Knowledge engineering for complex knowledge
CKR-1
Conclusions
2
3
Introduction
Knowledge representation a key issue in AI/KB systems
knowledge is a discrete component
Modelling of complex knowledge a standing problem
Defined as deep inter-related knowledge concerning a
complex object, idea, process, behavior or system.
Example tax code, EPA regulations, investment knowledge..
Useful in knowledge-based systems, KM
4
Some classical problems in KR
primitive selection and granularity
choice of primitives
primitive relationships
network partitioning
selective inheritance
non-monotonic reasoning & belief revision
closed world assumption
probabilistic & temporal reasoning
quantification (some persons are mortal)
5
6
Relevant Literature
Seminal work in the ‘70’s & 80’s
Generalized representation languages
e.g. KL-One [Brachman & Schmolze ‘85], Loom
[MacGregor ‘99],
….Classic [Patel-schneider ‘91], KRS [Marcke et al. ‘87]
Specialized schemes adapted to a particular domain
e.g. geometric fig. [Lee ’88], IR [Gomez ’98; Zarri ‘01]
.. internet [Heflin et al. ‘99], NL [Sowa ‘94]
Recent emphasis on procedural, ontological, multi-paradigm schemes
plus text processing
procedural – e.g. CBR [Zeng et al. 06], neural nets [Kurfess ‘99]
ontological – e.g. TOB [Zhang et al. 08], BPM [Hepp 06]
multi-paradigm schemes – e.g. KROL [Shaalan et al. ‘99]
text processing & IR schemes – e.g. [Zhao et al. ’12]
7
KL-ONE [Brachman & Schmolze ‘85]
red
thing
blue
person
John
Ferrari
Mary
car
Grand Prix
Nexus 1
Context 1
Modelling concepts with KL-One
8
LOOM [MacGregor ‘99]
(defconcept Person)
(defrelation has-child :domain Person :range Person)
(defconcept Male)
(defconcept Person-with-Sons
:is (:and Person (:at-least 1 has-child Male)))
(defconcept Person-with-Two-Sons
:is (and Person (:exactly 2 has-child Male)))
(tell (Person Fred))
(tell (has-child Fred Sandy))
(tell (Male Sandy))
9
Conceptual Graphs [Sowa ‘94]
Van leaves BSS at 11:00 am and goes to Elnet
BSS
origin
Leaves
dest.
Elnet
Subj.
Van
Consider: rate making is the process by which insurers determine
the rates for each category or classification, of similar, but
independent insureds.
10
DOGMA-MESS [Christeans and Moor ‘06]
uses
material
uses
tool
results-in
product
done-by
actor
Process
11
MULTI-NETS [Helbig ‘05]
On July 8, 1497, Vasco De Gama led a
fleet of four ships with a crew of 170
men from Lisbon and sailed 6,000 miles
to reach the shores of India
12
KR Features of Selected KR Schemes
13
Limitations of Existing Approaches
Lack of continuity in KR 1̴ 995
Literature sparse for generalized schemes
business knowledge, complex knowledge, graphical schemes
No formal studies of domain characteristics
Conceptual and epistemic levels still problematic
Lack of emphasis on relationships and knowledge structuring
primitives
Multi-nets recent and comprehensive
14
Limitations of Ontologies
Usually in very structured domains
welding [Kitamura and Mizoguchi 2003]
BPM [Hepp and Roman 2007]
TOB [Zhang 2008]
Relationships are rigid and pre-visioned
e.g. PROCESS uses TOOL [Christaens and Moor 2006]
e.g. PROCESS results-in PRODUCT [ibid]
Ontology visualization [Hepp 2008]
very simple notation
use UML
Tend not to be interchangeable
15
16
Examples of complex knowledge
[Luthardt et al. 2005]
“Property includes real property and personal property. Real property is lands,
buildings and other property attached to it.” §1.6
“A liability loss exposure is any condition or situation that presents the
possibility of a claim alleging legal responsibility of a person or business for
injury or damage suffered by another party.” § 1.6
“Types of insurers include stock insuers, mutual insurers and reciprocal
exchanges” § 1.11
“Depreciation is allowance for physical wear and tear or technological or
economic obsolescence” § 6.14
“A contract of good faith is an obligation to act in an honest manner and to
disclose all relevant facts.” § 7.7
17
Characteristics of complex knowledge
describe objects, events, actions, situations & concepts
objects generally concrete
concepts generally abstract
concepts involve other concepts
mathematical
structural
axiomatic
logical
concepts may involve undefined concepts
alternatively, elaboration on concepts
conditions and restrictions may be imposed
CK – complex knowledge
18
19
Knowledge Engineering for CK
committed to graphical notation
representational adequacy an ideal
support:
concept definition, reuse
multiple definitions
modularity (network partitioning)
simple and complex relationships
pre-defined relationships (structural, logical etc.)
as well as arbitrary
20
21
CKR-1 Constructs
Simple/atomic concept, object/ instance or variable
E/S
Simple event/situation
A
Simple activity
Complex Concept, object
E/A
Complex Event or Activity
Name
Derived Concept ( Complex)
Connector for 2 or more concepts/ objects/ events
Multiple Arguments (and)
Multiple Arguments (and/or)
22
CKR-1 Logical Operators
Adapted from [Schubert 1976]
True
if
False
Negation
Then part of an if
Quantification
=
Equivalence
23
CKR-1 Relationships
Type
Format
Examples
Comments
Structural (s:)
s: <relationship>
is_a, p_sp, has_a, cmp_of,
sm_as, ag_of
Amaravadi [2005]
Descriptive (d:)
d-bus: <relationship>
d-cause: <relationship>
d-log: <relationship>
d-math: <relationship>
d-perm: <relationship>
d- prob: <relationship>
d-proc: <relationship>
d-qual: <relationship>
d-quant: <relationship>
d-state: <relationship>
d-temp: <relationship>
d-case: <relationship>
-ACTS, APL..
-CAU, RSLTS, ANS, QUES.
- GT, LT, LE, EQ, NOT..
- SUM, AVG..
-GRNT, RVK, LIC, PMT..
-PR, EX, NX..
-LP, NXT, PRV, INP
-GOOD, BAD, ACCU, ERR
-VOL, AREA, WGHT..
-ST, BT, WT
-BFR, AFR, DUR, AT, ALWY
-OBJ, INST, AGNT, SUB
Experience
Schank and Abelson
[1977], Axelrod
[1976], Schubert et
al. [1979], Prescott
et al. [2010], Riddle
[1996].
p: <property name>
p: number of members
rp: <property name>
rp: minimum number of
members.
from experience
and traditional KR
work.
property
relationships (p:)
Allen [1983],
Fillmore [1967],
e: <label> or <relationship>
24
Representing simple knowledge
An unnatural event is an earthquake, fire, flood, storm..
E
Unnatural event
s: is - a
E
Fire
E
Flood
25
Simple Knowledge is not Always
Simple
Board of
directors
s:cmp-of
s:cmp-of
person
Elected
officials
s:is-a
position
rp: method of
appointment
voting
“The BOD consists of elected officials”
[Luthardt et al. 2005]
26
Derived Concepts and Descriptive
Relationships
DAMAGE
d-temp: AFTR
Damaged Entity
Damaged Entity
rp: ST
rp: ST
d-state:WT
X
c
damage
Y
Damage is defined as worsening of the state of an entity
27
Complex Knowledge with Elaboration,
Relationships & Variables
E
Unnatural event
e:CAU
DAMAGE
d-temp: AFTR
Damaged Entity
Damaged Entity
rp: ST
rp: ST
d-state:WT
X
c
damage
Y
Worsening of state is caused by an unatural event
28
More Relationship Types and
Multiplicity
LOSS1
d-cause: CAU
E
Unnatural
event
A
damage
Damage
d-case: OBJ.
c
Damaged
damage
entity
Loss is damage to an entity as a result of an unnatural
event. Note that damaged entity can be a person, livestock etc.
[Luthardt et al. 2005]
29
Another way to represent loss:
Multiplicity
E
Unnatural event
LOSS2
e:CAU
Damaged entity
value
d-log:GT
Damaged entity
value
p: time
p: time
c
T1
T2
d-temp: AFTR
Loss can be a decrease in value of a damaged entity
30
User Defined Concepts and
Variables
COVERAGE1
d-case: SUBJ
Insured
E
damage
Loss
rp: loss amount
c
LAMOUNT
damage
Insurance coverage is the legal obligation of underwriter to compensate
insured in the event of a loss – here insured suffers loss
31
User Defined Concepts..
COVERAGE2
d-bus PP
Underwriter
Insured
damage
e: loss amount
damage
LAMOUNT
c
Underwriter compensates insured for loss amount
32
Propositions with User Defined
Concepts
COVERAGE
Coverage1
Coverage2
damage
Coverage = Coverage1 and Coverage2
33
Concept Definition & Extension
insurancepolicy
d-bus: COCO
insurer
insured
rights
d-bus: LERQ
d-bus: LERQ
duties
An insurance policy defines in detail the rights and
duties of both parties to the contract: the insured and
insurer.
34
Adding to Concept Definition..
insurancepolicy+
s:has-a
coverage
insured
rp:DUR
Time period
An insurance policy provides coverage for a specified
time period.
35
More complex knowledge..
“many states require
insurers to file their
policy forms with the
state department in a
manner similar to the
method used for rate
filing.
USA
law
s:ag-of
s:sm-as
s:has-a
requirement
States
many
s:has-a
d-bus:APL
d-proc: FILE
State insurance
department
insurer
A
e-method
s:is-a
Rate filing
d-cause:OBJ
d-log: SIM
s:is-a
X
Y
Policy form
36
Can we represent this?
“Indemnify means to restore a party who has suffered loss to the
same financial position that the party held before the loss.”
“Liability insurance covers liability loss exposures. It provides for
payment on behalf of the insured for injury to others or damage to
other’s property for which the insured is legally responsible.”
“Replacement cost is the cost to repair or replace property using
new materials of like kind and quality with no deduction for
depreciation.”
“Salvage rights are the insurer’s rights to recover and sell or
otherwise dispose of insured property on which the insurer has
paid a total loss or a constructive total loss.”
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EVALUATION AND CONCLUSIONS
38
Quantitative Evaluation
Evaluation of Expressivity in CKR-1
Result (n = 50)
Number of cases
%
Percentage successful
39
78%
Partially successful
1
2%
Could not represent
10
20%
39
Qualitative Evaluation
Criteria
Comments
selective inheritance
no
reasoning with defaults
no
probabilistic knowledge
yes – encoded as ‘dprob’relationship.
beliefs
no
prepositions
yes
negation
yes
quantification
yes quantification operator;
conjunctions, disjunctions, and/or
yes
temporal reasoning
some temporality included
incomplete knowledge
yes
40
Conclusions
graphical method designed for abstract, complex,
specialized domains
abstractions/partitioning
multiple methods of definition
some integration of ideas; elements of:
logical & partitioned networks
case frames & concept graphs
designed also for usability and re-usability
graphical
can be used in multiple domains (FR)
modularization
very flexible -- arbitrary concepts & relationships
some limitations (FR)
Note: FR – Future Research
41
Questions?
42