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Semantics for Biodiversity. Barry Smith http://ontology.buffalo.edu/smith. A brief history of the Semantic Web. html demonstrated the power of the Web to allow sharing of information - PowerPoint PPT Presentation
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A brief history of the Semantic Web
• html demonstrated the power of the Web to allow sharing of information
• can we use semantic technology to create a Web 2.0 which would allow algorithmic reasoning with online information based on XLM, RDF and above all OWL (Web Ontology Language)?
• can we use RDF and OWL to break down silos, and create useful integration of on-line data and information
2/24
people tried, but the more they were successful, they more they failed
OWL breaks down data silos via controlled vocabularies for the description of data dictionaries
Unfortunately the very success of this approach led to the creation of multiple, new, semantic silos – because multiple ontologies are being created in ad hoc ways
3/24
Ontology success stories, and some reasons for failure
•
A fragment of the “Linked Open Data” in the biomedical domain
4
What you get with ‘mappings’
HPO: all phenotypes (excess hair loss, duck feet ...)
NCIT: all organisms
What you get with ‘mappings’
all phenotypes (excess hair loss, duck feet)
all organisms
allose (a form of sugar)
7
What you get with ‘mappings’
all phenotypes (excess hair loss, duck feet)
all organisms
allose (a form of sugar)
Acute Lymphoblastic Leukemia (A.L.L.)
8
Mappings are hard
They are fragile, and expensive to maintainNeed a new authority to maintain, yielding new
risk of forkingThe goal should be to minimize the need for
mappingsInvest resources in disjoint ontology modules
which work well together – reduce need for mappings to minimum possible
9
Why should you care?
• you need to create systems for data mining and text processing which will yield useful digitally coded output
• if the codes you use are constantly in need of ad hoc repair huge resources will be wasted
• relevant data will not be found• serious reasoning will be defeated from the
start
10/24
How to do it right?
• how create an incremental, evolutionary process, where what is good survives, and what is bad fails
• where the number of ontologies needing to be linked is small
• where links are stable• create a scenario in which people will find it
profitable to reuse ontologies, terminologies and coding systems which have been tried and tested
11/24
GO provides a controlled system of terms for use in annotating (describing, tagging) data
• multi-species, multi-disciplinary, open source
• contributing to the cumulativity of scientific results obtained by distinct research communities
• compare use of kilograms, meters, seconds in formulating experimental results
14
Pleural Cavity
Pleural Cavity
Interlobar recess
Interlobar recess
Mesothelium of Pleura
Mesothelium of Pleura
Pleura(Wall of Sac)
Pleura(Wall of Sac)
VisceralPleura
VisceralPleura
Pleural SacPleural Sac
Parietal Pleura
Parietal Pleura
Anatomical SpaceAnatomical Space
OrganCavityOrganCavity
Serous SacCavity
Serous SacCavity
AnatomicalStructure
AnatomicalStructure
OrganOrgan
Serous SacSerous Sac
MediastinalPleura
MediastinalPleura
TissueTissue
Organ PartOrgan Part
Organ Subdivision
Organ Subdivision
Organ Component
Organ Component
Organ CavitySubdivision
Organ CavitySubdivision
Serous SacCavity
Subdivision
Serous SacCavity
Subdivision
part
_of
is_a
17
Reasons why GO has been successful
It is a system for prospective standardization built with coherent top level but with content contributed and monitored by domain specialists
Based on community consensusUpdated every nightClear versioning principles ensure backwards
compatibility; prior annotations do not lose their value
Initially low-tech to encourage users, with movement to more powerful formal approaches (including OWL-DL – though GO community still recommending caution)
18
GO has learned the lessons of successful cooperation
• Clear documentation• Fully open source (allows thorough testing in
manifold combinations with other ontologies)• Subjected to considerable third-party critique• Rapid turnaround tracker and help desk• Usable also for education • The terms chosen are already familiar
GO has been amazingly successful in overcoming the data balkanization
problembut it covers only generic biological entities of three sorts:
– cellular components– molecular functions– biological processes
and it does not provide representations of diseases, symptoms, …
20
RELATION TO TIME
GRANULARITY
CONTINUANT OCCURRENT
INDEPENDENT DEPENDENT
ORGAN ANDORGANISM
Organism(NCBI
Taxonomy)
Anatomical Entity(FMA, CARO)
OrganFunction
(FMP, CPRO) Phenotypic
Quality(PaTO)
Biological Process
(GO)CELL AND CELLULAR
COMPONENT
Cell(CL)
Cellular Compone
nt(FMA, GO)
Cellular Function
(GO)
MOLECULEMolecule
(ChEBI, SO,RnaO, PrO)
Molecular Function(GO)
Molecular Process
(GO)
Original OBO Foundry ontologies (Gene Ontology in yellow) 21
22
RELATION TO TIME
GRANULARITY
CONTINUANT OCCURRENT
INDEPENDENT DEPENDENT
ORGAN ANDORGANISM
Organism(NCBI
Taxonomy)
Anatomical Entity(FMA, CARO)
OrganFunction
(FMP, CPRO) Phenotypic
Quality(PaTO)
Biological Process
(GO)CELL AND CELLULAR
COMPONENT
Cell(CL)
Cellular Compone
nt(FMA, GO)
Cellular Function
(GO)
MOLECULEMolecule
(ChEBI, SO,RnaO, PrO)
Molecular Function(GO)
Molecular Process
(GO)
Environment Ontology
envi
ron
men
ts
are
her
e
23
RELATION TO TIME
GRANULARITY
CONTINUANT OCCURRENT
INDEPENDENT DEPENDENT
COMPLEX OFORGANISMS
Population and Community
Ontology (PCO) OrganFunction
(FMP, CPRO)
Population Phenotype
PopulationProcess
ORGAN ANDORGANISM
Organism(NCBI
Taxonomy)
Anatomical Entity(FMA, CARO) Phenotypic
Quality(PaTO)
Biological Process
(GO)CELL AND CELLULAR
COMPONENT
Cell(CL)
Cellular Componen
t(FMA, GO)
Cellular Function
(GO)
MOLECULEMolecule
(ChEBI, SO,RnaO, PrO)
Molecular Function(GO)
Molecular Process
(GO)http://obofoundry.org
24
RELATION TO TIME
GRANULARITY
CONTINUANT OCCURRENT
INDEPENDENT DEPENDENT
COMPLEX OFORGANISMS
Family, Community, Deme, Population
OrganFunction
(FMP, CPRO)
Population Phenotype
PopulationProcess
ORGAN ANDORGANISM
Organism(NCBI
Taxonomy)
Anatomical Entity(FMA, CARO) Phenotypic
Quality(PaTO)
Biological Process
(GO)CELL AND CELLULAR
COMPONENT
Cell(CL)
Cellular Componen
t(FMA, GO)
Cellular Function
(GO)
MOLECULEMolecule
(ChEBI, SO,RnaO, PrO)
Molecular Function(GO)
Molecular Process
(GO)
http://obofoundry.org
Developers commit to working to ensure that, for each domain, there is community convergence on a single ontology
and agree in advance to collaborate with developers of ontologies in adjacent domains.
http://obofoundry.org
The OBO Foundry: a step-by-step, evidence-based approach to expand
the GO
25
OBO Foundry Principles
Common governance (coordinating editors)
Common training
Common architecture
• simple shared top level ontology (Basic Formal Ontology)
• shared Relation Ontology: www.obofoundry.org/ro
26
Open Biomedical Ontologies Foundry
Seeks to create high quality, validated terminology modules across all of the life sciences which will be
• close to language use of experts
• evidence-based
• incorporate a strategy for motivating potential developers and users
• revisable as science advances
• modularity: one ontology for each domain
27
28
Modularity
ensures • annotations can be additive• no need for mappings• division of labor amongst domain experts• high value of training in any given module• lessons learned in one module can benefit
work on other modules• incentivization of those responsible for
individual modules
The Modular Approach• Create a small set of plug-and-play ontologies as
stable monohierarchies with a high likelihood of being reused
• Create ontologies incrementally• Reuse existing ontology resources• Use these ontologies incrementally in annotating
heterogeneous data• Annotating = arms length approach; the data and
data-models themselves remain as they are
29
Logical standards can be only part of the solution
OWL … bring benefits primarily on the side of syntax (language)
What we need are standards on the semantics (content) side (via top-level ontologies), including standards for•top-level ontologies•common relations (part_of …)•relation of lower-level ontologies to each other and to the higher levels
120+ ontology projects using BFO
http://www.ifomis.org/bfo/
• Open Biomedical Ontologies Foundry • Ontology for General Medical Science• eagle-I, VIVO, CTSAconnect• AstraZeneca • Elsevier
How a common upper level ontology can help resist ontology chaos
• something to teach• training (expertise) is portable• each new ontology you confront will be more easily
understood at the level of content– and more easily criticized, error-checked
• provides starting-point for domain-ontology development
• provides platform for tool-building and innovations• lessons learned in building and using one ontology
can potentially benefit other ontologies• promote shareability of data across discilinary and
other boundaries
Anatomy Ontology(FMA*, CARO)
Environment
Ontology(EnvO)
Infectious Disease
Ontology(IDO*)
Biological Process
Ontology (GO*)
Cell Ontology
(CL)
CellularComponentOntology
(FMA*, GO*) Phenotypic Quality
Ontology(PaTO)
Subcellular Anatomy Ontology (SAO)Sequence Ontology
(SO*) Molecular Function
(GO*)Protein Ontology(PRO*) OBO Foundry Modular Organization
top level
mid-level
domain level
Information Artifact Ontology
(IAO)
Ontology for Biomedical Investigations
(OBI)
Ontology of General Medical Science
(OGMS)
Basic Formal Ontology (BFO)
38
BFO
A simple top-level ontology to support information integration in scientific research
•No overlap with domain ontologies (organism, person, society, information, …)
•Based on realism
•No abstracta
•Tested in many natural science domains
39
Basic Formal Ontology
Continuant Occurrent
process, eventIndependentContinuant
entity
DependentContinuant
property
property dependson bearer
40
depends_on
Continuant Occurrent
process, eventIndependentContinuant
thing
DependentContinuant
property event dependson participant
41
Basic Formal Ontology
continuant occurrent
biological processes
independentcontinuant
cellular component
dependentcontinuant
molecular function
roles, qualities
Continuant Occurrent
process, eventIndependentContinuant
DependentContinuant
43
Quality Disposition
instance_of
Continuant Occurrent
process, eventIndependentContinuant
thing
DependentContinuant
property
.... ..... .......
types
instances 44
CONTINUANT OCCURRENT
INDEPENDENT DEPENDENT
ORGAN ANDORGANISM
Organism(NCBI
Taxonomy)
Anatomical Entity
(FMA, CARO)
OrganFunction
(FMP, CPRO) Phenotypic
Quality(PaTO)
Organism-Level Process
(GO)
CELL AND CELLULAR
COMPONENT
Cell(CL)
Cellular Compone
nt(FMA, GO)
Cellular Function
(GO)
Cellular Process
(GO)
MOLECULEMolecule
(ChEBI, SO,RNAO, PRO)
Molecular Function(GO)
Molecular Process
(GO)
rationale of OBO Foundry coverage
GRANULARITY
RELATION TO TIME
45
coronary heart disease
John’s coronary heart disease
50
CHD in phase of asymptomatic
(‘silent’) infarction
CHD in phase of early lesions
and small fibrous plaques
stable angina
CHD in phase of surface
disruption of plaque
unstable angina
instantiates at t1
instantiates at t2
instantiates at t3
instantiates at t4
instantiates at t5
in nature, no sharp boundaries here
human
John
51
embryo fetus adultneonate infant child
instantiates at t1
instantiates at t2
instantiates at t3
instantiates at t4
instantiates at t5
instantiates at t6
in nature, no sharp boundaries here
A disease is a disposition
etiological process
produces
disorder
bears
disposition
realized_in
pathological process
produces
abnormal bodily features
recognized_as
signs & symptomsinterpretive process
produces
diagnosis
used_in52
Cirrhosis - environmental exposure Etiological process - phenobarbitol-
induced hepatic cell death produces
Disorder - necrotic liver bears
Disposition (disease) - cirrhosis realized_in
Pathological process - abnormal tissue repair with cell proliferation and fibrosis that exceed a certain threshold; hypoxia-induced cell death produces
Abnormal bodily features recognized_as
Symptoms - fatigue, anorexia Signs - jaundice, splenomegaly
Symptoms & Signs used_in
Interpretive process produces
Hypothesis - rule out cirrhosis suggests
Laboratory tests produces
Test results - elevated liver enzymes in serum used_in
Interpretive process produces
Result - diagnosis that patient X has a disorder that bears the disease cirrhosis
53
HNPCC - genetic pre-disposition
Etiological process - inheritance of a mutant mismatch repair gene produces
Disorder - chromosome 3 with abnormal hMLH1 bears
Disposition (disease) - Lynch syndrome realized_in
Pathological process - abnormal repair of DNA mismatches produces
Disorder - mutations in proto-oncogenes and tumor suppressor genes with microsatellite repeats (e.g. TGF-beta R2) bears
Disposition (disease) - non-polyposis colon cancer realized in
Symptoms (including pain)
55
Ontology modules extending of OGMS
Sleep Domain Ontology (SDO)
Ontology of Medically Relevant Social Entities (OMRSE)
Vital Sign Ontology (VSO)
Mental Disease Ontology (MD)
Neurological Disease Ontology (ND)
Infectious Disease Ontology (IDO)
56
Infectious Disease Ontology (IDO)
– IDO Core: • General terms in the ID domain. • A hub for all IDO extensions.
– IDO Extensions: • Disease specific. • Developed by subject matter experts.
• Provides:– Clear, precise, and consistent natural language
definitions– Computable logical representations (OWL, OBO)
How IDO evolvesIDOCore
IDOSa
IDOHumanSa
IDORatSa
IDOStrep
IDORatStrep
IDOHumanStrep
IDOMRSa
IDOHumanBacterial
IDOAntibioticResistant
IDOMAL IDOHIVCORE and SPOKES:Domain ontologies
SEMI-LATTICE:By subject matter experts in different communities of interest.
IDOFLU
IDO Core
• Contains general terms in the ID domain:– E.g., ‘colonization’, ‘pathogen’, ‘infection’
• A contract between IDO extension ontologies and the datasets that use them.
• Intended to represent information along several dimensions:– biological scale (gene, cell, organ, organism, population)– discipline (clinical, immunological, microbiological) – organisms involved (host, pathogen, and vector types)
Sample IDO Definitions
• Host of Infectious Agent (BFO Role): A role borne by an organism in virtue of the fact that its extended organism contains an infectious agent.
• Extended Organism (OGMS): An object aggregate consisting of an organism and all material entities located within the organism, overlapping the organism, or occupying sites formed in part by the organism.
• Infectious Agent: A pathogen whose pathogenic disposition is an infectious disposition.
Staphylococcus aureus (Sa)
MSSa MRSa
HA-MRSa CA-MRSa
UK CA-MRSa Australian CA-MRSa
Specific Strains
{Antibiotic Resistance
{Pathogenesis Location Type
{Geographic Region
{Various Differentia
Differentiated by:
Sample Application: A lattice of infectious disease application ontologies from NARSA isolate data
Network on Antimicrobial Resistance in Staphylococcus aureus–http://www.narsa.net/content/staphLinks.jsp
True personalized medicine – YourDiseaseOntology
Ways of differentiating Staphylococcus aureus infectious diseases
• Infectious Disease– By host type– By (sub-)species of pathogen– By antibiotic resistance– By anatomical site of infection
• Bacterial Infectious Disease– By PFGE (Strain)– By MLST (Sequence Type)– By BURST (Clonal Complex)
• Sa Infectious Disease– By SCCmec type
• By ccr type• By mec class
– spa type
International Working Group on the Staphylococcal Cassette Chromosome elements
BFO: The Very Top
continuant
independentcontinuant
dependentcontinuant
qualityfunctionroledisposition
occurrent
Basic Formal Ontology
Continuant Occurrent
process, eventIndependentContinuant
thing
DependentContinuant
quality
.... ..... .......
types
instances
Basis of BFO in GO
Continuant Occurrent
biological processIndependent
Continuant
cellular component
DependentContinuant
molecular function
..... ..... ........
How a common upper level ontology can help resist ontology chaos
something to teachtraining (expertise) is portableeach new ontology you confront will be more easily
understood at the level of contentand more easily criticized, error-checked
provides starting-point for domain-ontology development
provides platform for tool-building and innovations• lessons learned in building and using one
ontology can potentially benefit other ontologies• promote shareability of data across discilinary
and other boundaries
71
Entity =def
anything which exists, including things and processes, functions and qualities, beliefs and actions, documents and software
(entities on levels 1, 2 and 3)
72
First basic distinction among entities
type vs. instance
(science text vs. diary)
(human being vs. Tom Cruise)
74
A 515287 DC3300 Dust Collector Fan
B 521683 Gilmer Belt
C 521682 Motor Drive Belt
Catalog vs. inventory
80
An ontology is a representation of types
We learn about types in reality from looking at the results of scientific experiments in the form of scientific theories
experiments relate to what is particular science describes what is general
82
Pleural Cavity
Pleural Cavity
Interlobar recess
Interlobar recess
Mesothelium of Pleura
Mesothelium of Pleura
Pleura(Wall of Sac)
Pleura(Wall of Sac)
VisceralPleura
VisceralPleura
Pleural SacPleural Sac
Parietal Pleura
Parietal Pleura
Anatomical SpaceAnatomical Space
OrganCavityOrganCavity
Serous SacCavity
Serous SacCavity
AnatomicalStructure
AnatomicalStructure
OrganOrgan
Serous SacSerous Sac
MediastinalPleura
MediastinalPleura
TissueTissue
Organ PartOrgan Part
Organ Subdivision
Organ Subdivision
Organ Component
Organ Component
Organ CavitySubdivision
Organ CavitySubdivision
Serous SacCavity
Subdivision
Serous SacCavity
Subdivision
part
_of
is_a
3 kinds of (binary) relations
Between types
• human is_a mammal
• human heart part_of human
Between an instance and a type
• this human instance_of the type human
• this human allergic_to the type tamiflu
Between instances
• Mary’s heart part_of Mary
• Mary’s aorta connected_to Mary’s heart83
Type-level relations presuppose the underlying instance-level relations
A is_a B =def. A and B are types and all instances of A are instances of B
A part_of B =def. All instances of A are instance-level-parts-of some instance of B
84
The assertions linking terms in ontologies must hold universally
Hence all type-level relations in RO are provided with
All-Some definitions
If you know A part_of B, and B part_of C then whichever A you
choose, the instance of B of which it is a part will be included in
some C, which will include as part also the A with which you
began
85
86
part_offor continuant classes is
time-indexed
A part_of B =def.given any particular a and any time t, if a is an instance of A at t,then there is some instance b of B such that a is an instance-level part_of b at t
89
transformation_of
C2 transformation_of C1 =def. any instance
of C2 was at some earlier time an instance
of C1
92
The Granularity Gulf
most existing data-sources are of fixed, single granularity
many (all?) clinical phenomena cross granularities
94
universality
Often, order will matter:
We can assert
adult transformation_of child
but not
child transforms_into adult
95
Representation =def
an image, idea, map, picture, name or description ... of some entity or entities.
Ontologies are structured representations of the types in a certain domain of reality
102
Inventory vs. Catalog:Two kinds of representational
artifact
Databases represent instances
Ontologies represent types
103
How do we know which general terms designate types?
Types are repeatables:
cell, electron, weapon, mouse ...
Instances are one-off: Bill Clinton, this mouse …
104
Problem
The same general term can be used to refer both to types and to collections of particulars. Consider:
HIV is an infectious retrovirus
HIV is spreading very rapidly through Asia
105
Class =def
a maximal collection of particulars determined by a general term (‘cell’, ‘electron’ but also: ‘ ‘restaurant in Palo Alto’, ‘Italian’)
the class A = the collection of all particulars x for which ‘x is A’ is true
110
types vs. classes
types
populations, ...
the class of all diabetic patients in Leipzig on 4 June 1952
111
OWL is a good representation of classes
• F16s
• sibling of Finnish spy
• member of Abba aged > 50 years
113
types < classes < ‘concepts’
Cases of ‘concepts’ which do not correspond to classes:
‘Cancelled manoeuvre’‘Planned manoeuvre’‘Fake terrorist’
Such terms do not represent anythingSee Information Artifact Ontology (IAO)
114
Ontology =def.
a representational artifact whose representational units (which may be drawn from a natural or from some formalized language) are intended to represent
1. types in reality
2. those relations between these types which obtain universally (= for all instances)
lung is_a anatomical structure
lobe of lung part_of lung
115
BFO Top-Level Ontology
ContinuantOccurrent
(always dependent on one or more
independent continuants)
IndependentContinuant
DependentContinuant
116
Two kinds of entities
occurrents (processes, events, happenings)
continuants (objects, qualities, states...)
117
Continuants (aka endurants)have continuous existence in timepreserve their identity through changeexist in toto whenever they exist at all
Occurrents (aka processes)have temporal partsunfold themselves in successive phasesexist only in their phases
119
Dependent entities
require independent continuants as their bearers
There is no run without a runner
There is no grin without a cat
120
Dependent vs. independent continuants
Independent continuants (organisms, buildings, environments)
Dependent continuants (quality, shape, role, propensity, function, status, power, right)
121
All occurrents are dependent entities
They are dependent on those independent continuants which are their participants (agents, patients, media ...)
122
BFO Top-Level Ontology
ContinuantOccurrent
(always dependent on one or more
independent continuants)
IndependentContinuant
DependentContinuant
OBO Foundry organized in terms of Basic Formal Ontology
Each Foundry ontology can be seen as an extension of a single upper level ontology (BFO)
either post hoc, as in the case of the GO
or in virtue of creation ab initio via downward population from BFO
123
124
How to build an ontologyimport BFO into ontology editor
work with domain experts to create an initial mid-level classification
find ~50 most commonly used terms corresponding to types in reality
arrange these terms into an informal is_a hierarchy according to this universality principle
A is_a B every instance of A is an instance of B
fill in missing terms to give a complete hierarchy
(leave it to domain experts to populate the lower levels of the hierarchy)
quality: John’s blood glucose level
participates_inOBI process:
this specific assay
inheres_in
John
deviceparticipates_in
part_of screen
has_specified_output
quality: ‘120 mg/dL’-shaped
pattern
IAO:measurement datum
is_about concretized_by
inheres_inportion of blood
derived_from
Numerical Value Example
Quality of portion of blood
elements of an ontological analysis: 1.the portion of blood (material entity)2.the blood sugar level (quality) referred to by means of 3.an expression (information artifact, thus a BFO:generically dependent continuant) ‘100 mg/dL’.
process: John’s heart beating
has_participantOBI process:
this specific assay
has_participant
John
device
has_participant
has_part screen
has_specified_output quality: ‘120
bpm’-shaped pattern
IAO:measurement datum
is_about concretized_by
inheres_in
Beat Measurement
Process measurement
heart beating at constant rate, elements of an ontological analysis: 1.the heart (object)2.the process of beating3.the temporal region occupied by this process4.the spatiotemporal region that is occupied by this process (trajectory of the beating process)5.the rate, referred to by means of 6.an expression (information artifact, thus a BFO:generically dependent continuant) such as ‘63 beats/minute’.
process: John’s heart beating
has_participant
measurement process:
this specific assay
has_participant
John
device
has_participant
has_partscreen
has_specified_output quality: ‘120
bpm’-shaped pattern
IAO:measurement datum
is_about concretized_by
inheres_in
Beat Measurement
The Information Artifact Ontology
credit card numbers are not integers
names are not strings
serial numbers are not strings
Rather, they are artifacts, human creations.
If my Social Security Number is the same integer as your Credit Card Number, they are still different Numbers
If my name is the same string as your name, they are still different names
134
Information Entity (labeling)
serial numberbatch numbergrant numberperson numbernameaddressemail addressURL...
136
What is a datum?
Continuant Occurrent
processIndependentContinuant
laptop, book
DependentContinuant
quality
.... ..... .......datum: a pattern in some medium with a certain kind of provenance
138
type or instance
ContinuantOccurrent(Process)
IndependentContinuant
human being,protocol document
DependentContinuant
pattern of ink marks
Applying the protocol
Side-Effect …
...... ..... .... .....139
Continuant Occurrent
IndependentContinuant
DependentContinuant
.... ..... .......
InformationEntity
Action
creating a datum
140
Type: human beingInstance: Leon Tolstoy
Type: novelInstance: War and Peace
Type: bookInstance: this copy of War and Peace
types and instances
141
Is War and Peace a type or an instance?If War and Peace were a type, and the copies of War and Peace in my library and in your library were instances, then
• there would be many War(s) and Peaces.
Hence War and Peace is an instance.
What is a work of literature?
142
There can be two copies of the Declaration of Independence
There cannot be two Declarations of Independence
There are not two Declarations of Independence
143
Syntactic rule of thumb for types
Their names are pluralizable
There can be three peopleThere cannot be three Condoleezza Rices
Information Entities = entities which can exist in many perfect copiesYour genome is an information entity, but not an information artifact
144
Specific dependence
Continuant Occurrent
process
IndependentContinuant
thing
DependentContinuant
quality
.... ..... .......headache dependson human being
145
Generically Dependent Continuants
GenericallyDependentContinuant
Information Entity
Sequence
if one bearer ceases to exist, then the entity can survive, because there are other bearers (copyability)
the pdf file on my laptop
the DNA (sequence) in this chromosome
146
are realized through being concretized in specifically dependent continuants(the plan in your head, the protocol being realized by your research team)
Generically dependent continuants
147
Types vs. generically dependent continuants
types have subtypes (kinds): if you can have a kind of something, then it’s a type
you can’t have a kind of Bill Clinton
you can’t have a kind of The Constitution of the United States
148
Generically Dependent Continuants
GenericallyDependentContinuant
Information Entity
Sequence
.pdf file .doc file
instances 149
are concretized in specifically dependent continuants
Beethoven’s 9th Symphony is concretized in the pattern of ink marks which make up this score in my hand
Generically dependent continuants
150
Realizable Dependent Continuants
SpecificallyDependentContinuant
Quality, PatternRealizable Dependent Continuant
inert ert
Occurrent
152
Examplesperformance of a symphonyprojection of a filmutterance of a sentenceapplication of a therapycourse of a diseaseincrease of temperature
OccurrentRealizable Dependent Continuant
153
154
Information Content Entity
Geospatial Entity
Entity
Road Intersecti
on
Property
Physical Propert
y
Geospatial Reference
Point
Designative Information
Content Entity
Physical
Location
Key:
Ontology Elements
Relations
Data Elements
is_a
is_a
is_a
is_a
is_a
is_a
is_a
String: Amazai and
Nawagai Sura Road
Intersection
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WPT: EZ497
Lat: 34.40393540678018
Long: 72.50272750854492
MGRS: TF 4679 5792
is_a
denotes
denotes
denotes denote
sdenote
s
Ontology
Data Model Elements
has_rolehas_propert
y
BFO: role• a realizable dependent continuant that is not the
consequence of the nature of the independent continuant entity which bears the role (contrast: disposition)
• the role is optional (someone else assigns it, the entity acquires it by moving it into a specific context)
• roles often come in pairs (husband/wife)
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ContinuantOccurrent
IndependentContinuant
Specifically DependentContinuant
Quality Disposition
Realization
Role
Realizable DependentContinuant
GenericallyDependentContinuant
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• standard examples: nurse, student, patient; • in each case something holds (that a person plays
a role) because of some socially vehiculated decision. Functions never exist purely because people decide that they exist; this is because functions rest in each case on some underlying physical structure with relevant causal powers.
Roles
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Principle of Low Hanging Fruit
Include even absolutely trivial assertions (assertions you know to be universally true)
pneumococcal bacterium is_a bacterium
Computers need to be led by the hand
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Principle of singular nouns
Terms in ontologies represent types
Goal: Each term in an ontology should represent exactly one type
Thus every term should be a singular noun
Principle: Avoid mass nouns
Brenda Tissue Ontology
blood is_a hematopoietic system
hematopoietic system is_a whole body
whole_body is_a animal
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Principle of definitions
Supply definitions for every term
1.human-understandable natural language definition
2.an equivalent formal definition
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Principle: definitions must be unique
Each term should have exactly one definition
it may have both natural-language and formal versions
(issue with ontologies which exist with different levels of expressivity)
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The Problem of Circularity
A Person =def. A person with an identity document
Hemolysis =def. The causes of hemolysis
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Principle of increase in understandability
A definition should use only terms which are easier to understand than the term defined
Definitions should not make simple things more difficult than they are
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Principle of acknowledging primitives
In every ontology some terms and some relations are primitive = they cannot be defined (on pain of infinite regress)
Examples of primitive relations:
identity
instance_of
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Principle of Aristotelian definitions
Use two-part definitions
An A is a B which C’s.
A human being is an animal which is rational
Here A is the child term, B is its immediate parent in the ontology is_a hierarchy
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Rules for formulating terms
Avoid abbreviations even when it is clear in context what they mean (‘breast’ for ‘breast tumor’)
Avoid acronymsAvoid mass terms (‘tissue’, ‘brain mapping’,
‘clinical research’ ...)Treat each term ‘A’ in an ontology is
shorthand for a term of the form ‘the type A’
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universality
Often, order will matter:
We can assert
adult transformation_of child
but not
child transforms_into adult
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universality
viral pneumonia caused by virus
but not
virus causes pneumonia
pneumococcal virus causes pneumonia
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Principle of Universality
results analysis later_than protocol-design
but not
protocol-design earlier_than results analysis
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Principle of positivityComplements of types are not themselves types.
Terms such as
non-mammal non-membrane other metalworker in New Zealand
do not designate types in reality
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Generalized Anti-Boolean Principle
There are no conjunctive and disjunctive types:
anatomic structure, system, or substance
musculoskeletal and connective tissue disorder
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Objectivity
Which types exist in reality is not a function of our knowledge.
Terms such as
unknown
unclassified
unlocalized
arthropathies not otherwise specified
do not designate types in reality.
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Keep Epistemology Separate from Ontology
If you want to say that
We do not know where A’s are located
do not invent a new class of
A’s with unknown locations
(A well-constructed ontology should grow linearly; it should not need to delete classes or relations because of increases in knowledge)
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If you want to say
I surmise that this is a case of pneumonia
do not invent a new class of surmised pneumonias
Confusion of ‘findings’ in medical terminologies
Keep Sentences Separate from Terms
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Principle: do not commit the use-mention confusion
mouse =def. common name for the species mus musculus
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Principle: do not commit the use-mention confusion
Avoid confusing between words and things
Avoid confusing between concepts in our minds and entities in reality
Recommendation: avoid the word ‘concept’ entirely
Species
species = reproductively isolated units that persist as continuants over time.
(one problem area: bacteria, noclear "reproductive isolation" and horizontal gene transfer.)
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