©2009 John Mylopoulos ER’09 -- 1 Conceptual Modelling in the Time of the Revolution: Part II ER’09, Gramado, Brazil November 11, 2009
©2009 John Mylopoulos ER’09 -- 1
Conceptual Modelling in the Time of the
Revolution: Part II
ER’09, Gramado, Brazil November 11, 2009
©2009 John Mylopoulos ER’09 -- 2
Abstract Conceptual Modeling (CM) was a marginal research area at the very
fringes of Computer Science (CS) in the 60s and 70s, when the discipline was dominated by topics focusing on programs, systems and hardware architectures. Over the years, however, This has changed over the past three decades, with CM playing a central role in CS research and practice in diverse areas, such as Software Engineering (SE), Databases (DB), Information Systems (IS), the Semantic Web (SW), Business Process Management (BPM), Service-Oriented Computing, Knowledge Management (KM), and more. The transformation was greatly aided by the adoption of standards for modeling languages (e.g., UML), and model-based methodologies (e.g., Model-Driven Architectures) by the Object Management Group (OMG), W3C, and other standards organizations.
We briefly review the history of the field over the past 40 years, focusing on the evolution of key ideas. We then note some open challenges, covering topics such as modelling businesses, cultural objects and laws.
©2009 John Mylopoulos ER’09 -- 3
Acknowledgements I am grateful to my colleagues and students whose ideas
are represented (… modelled!) in these slides. I am particularly grateful to three long-time
collaborators and friends: Alex Borgida who showed me the way on a formal grounding for conceptual modelling languages; Nicola Guarino who taught me the basics of ontological analysis; and Joachim Schmidt, who pointed me to a future for Conceptual Modelling.
©2009 John Mylopoulos ER’09 -- 4
… Twelve Years ago …
©2009 John Mylopoulos ER’09 -- 5
Conceptual Models ➥ Use domain-oriented concepts (e.g., entity,
relationship, goal, actor, …) and are structured according to cognitive principles (e.g., generalization, aggregation, classification, …).
➥ Adopt an associationist viewpoint: models consist of nodes that represent concepts and associations/links that represent semantic/episodic/other relationships between concepts.
➥ Associationism has a long (and illustrious!) history in Philosophy and Psychology that goes back to Plato and Aristotle.
©2009 John Mylopoulos ER’09 -- 6
Origins in Computer Science
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Conceptual Models
eats
has
isa
isa
isa
isa isa
M 1
M
M
Buy Supplies
Cultivate
Extract Seeds
Seed & Vegie Prices
Plan & Budget Weather
Plan Budget
Fertilizer
Seeds Plants
Vegetables
Pick Produce Vegetables
Grow Vegetables
Money
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Defining Moment for Conceptual Modelling (CM)
"...The entity-relationship model adopts ... the natural view that the real world consists of
entities and relationships... (The entity-relationship model) incorporates some of the
important semantic information about the real world...”
[Chen75], VLDB’75
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1975-1997 – Exploring the Frontier ➥ Many applications
Design models for databases and software (DB, IS, SE) Knowledge-based systems (AI, IS) Knowledge management (AI, IS)
➥ Many modelling languages Dozens of proposals for semantic network-based languages, frame-based languages, description logics, … More dozens for semantic data models … Box-and-arrow notations in SE
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Basic Ontologies
[Mylopoulos97]
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Research Methodology I … The meaning triangle
Sign
Concept
Referent Tulips
1,2,3,4,5,6
Flower
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Research Methodology II New concepts for modelling applications; e.g.,
the use of the concept of goal to model software requirements in SE.
Formal semantics for modelling languages, and automated reasoning support for models.
Note: Throughout the ‘70s and ‘80s CM was a fringe research area in Computer Science.
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Pitfalls of Informal Models
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What Happened Next? The Semantic Web (Tim Berners-Lee et al) – web data
need to be encapsulated with their semantics, so that they can be processed automatically.
Model-Driven Software Engineering (OMG) – Software development consists of processes that create and manipulate chains of models ranging from problem-oriented, platform-independent ones to machine-oriented, platform-dependent ones.
Model Management (Phil Bernstein et al) – to cope with data complexity we need models (schemas, ontologies, …)
Ontological Analysis (Nicola Guarino et al) – “… content must be analyzed independently of the way it is represented …”
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The Semantic Web Use semantically rich ontologies to capture the semantics
of concepts and roles/relationships. This is accomplished by adopting Description Logics as
ontology modelling languages. Annotate web data with the concepts they instantiate, eg,
Some concerns: Capturing semantics through more expressive languages vs capturing semantics through a richer collection of primitive concepts [Borgida04].
More concerns: There is a lot more to making web data “machine processable” than semantic annotations, see data integration framework (DBs).
Even more concerns: Usability, scalability, …
<person> Paolo Buono <residence> lives in Trento </residence> and works at the <work> University of Trento </work> </person>
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“Far Side” take on the
Semantic Web
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Ontological Analysis (OA) Consider
2000 Presidential election: Is there a hole? 2001 World Trade Centre catastrophe: How many
events? Ontological analysis can answer these questions
Book by Roberto Casati and Achille C. Varzi (MIT Press):
• Holes and other superficialities
• Parts and places
[Guarino09]
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The Formal Tools of OA Theory of Essence and Identity Theory of Parts (Mereology) Theory of Unity and Plurality Theory of Dependence Theory of Composition and Constitution Theory of Properties and Qualities …
OA is to CM what Sub-atomic Physics is to Physics
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The State-of-the-Art in CM A large collection of modelling languages,
ranging from Description Logics, to the EER model and UML class diagrams (cum OCL).
Specialized languages for requirements, software architectures, various domains, …
Ontological Analysis. A growing number of relevant communities: ER,
KRR, FOIS, SemWeb, Models, CAiSE, RE, AAMAS, …
No longer a fringe research area within CS!
©2009 John Mylopoulos ER’09 -- 20
Looking Forward We understand very well static and dynamic
ontologies, pretty well intentional and social ones.
There are many applications out there that aren’t being served well with what we have so far … Business worlds Cultural worlds Legal worlds
©2009 John Mylopoulos ER’09 -- 21
Business Worlds There are many business modelling languages
(eg, UML extensions), business process modelling languages, business rule languages, …
We are interested in a language intended for governance -- i.e., a language that would allow a business to model its objectives, trends, threats, opportunities, etc., and monitor its daily activities to ensure compliance.
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An excellent Starting Point: A Business Ontology
There is an OMG standard (as of 2007) -- called the Business Motivation Model (BMM) -- intended precisely for business governance.
The standard includes a large number of concepts, ranging from {visions, objectives, goals} to {means strategies, plans}, to {metrics, indicators}, to {strengths, weaknesses, threats, vulnerabilities, opportunities).
But BMM is weak with respect the state-of-the-art on modelling languages (OA, DL-like definition of concepts, …)
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Example: Strategic Goals Largest
auto maker
Maintain status quo
Best auto maker
XOR Max customer
satisfaction
Happy customer
Quality product
Quality service
AND
Fuel prices
New technology
influences
influences
©2009 John Mylopoulos ER’09 -- 24
Governance according to BMM From control to governance
Means Ends
Influencers Assessments
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Cultural Worlds Art uses very rich
symbols, compared to those used in Science …
Science models rely on formalization for interpretation; art models depend on form & style for interpretation
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Art vs Science on Modelling “… In Kant’s expression, the natural sciences teach us to ‘spell out phenomena in order to read them off as experiences’; the science of culture teaches us to interpret symbols in order to decipher their hidden meaning, in order to make the life from which they originally emerged visible again …”
[Cassirer42, p.86]
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The Meaning Triangle Revisited
Flowers
Artist’s World Artifact
Intention
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The Meaning of Art Symbols Another excellent starting point: Artistic meaning has to
be understood at different levels of abstraction [Panofsky55] 0. Individual (existence level): plain media view (image,
text, speech, ...) 1. Characteristics (description level, pre-iconographic):
color, sizes, age,...; artists, periods, regions,…; content -- humans, animals, fruits, trees, ...
2. Iconography (meaning level): paradise, seducing Eve, curious Adam, tempting apple, sinful snake, ...
3. Iconology (effect level): Jewish and Christian ethics and legal systems, their origins and consequences, ...
[Schmidt09]
©2009 John Mylopoulos ER’09 -- 29
Legal Worlds Laws are notoriously difficult to understand
and use for purposes of law practice, as well as compliance.
Conceptual models of laws could be used to put on a more systematic footing software system & business process compliance.
Such models could also be used by lawyers and others who need to interpret and understand law.
For this domain too, there is an excellent starting point …
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Hohfeld’s Legal Ontology
Proposed almost a century ago [Hohfeld13]. Milestone in jurisprudence literature.
30
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Summary We are concerned with the design of conceptual
modelling languages and their use in building models for diverse domains.
Conceptual models are useful artifacts for purposes of understanding, communication, design, management, and more.
There has been much progress in spelling out the principles that underlie such languages …
…but much remains to be done.
©2009 John Mylopoulos ER’09 -- 32
“Move away from any narrow interpretation of databases and expand its focus to the hard problems faced by broad visions of data, information, and knowledge management”
Motto 12th International Joint Conference on Extending Database
Technology and Database Theory, Saint-Petersburg,
2009
©2009 John Mylopoulos ER’09 -- 33
[BMM07] Business Rules Group, “The Business Mo8va8on Model: BusinessGovernanceinaVola8leWorld”,Release1.3,September2007.[Borgida04]Borgida,A.,Mylopoulos,J.,“DataSeman8csRevisited”,VLDBWorkshopontheSeman8cWebandDatabases(SWDB’04),August2004,SpringerLNCS,9‐26.[Cassirer42],Cassirer,E., Zur Logik der Kulturwissenscha6en, Gšteborg, 1942;seealso:The Logic of the Cultural Sciences,YaleUniversityPress,2000.[Chen76]Chen,P.,“TheEn8ty‐Rela8onshipModel–TowardsaUnifiedViewofData”,ACM Transac@ons on Database Systems 1(1),1976.[Guarino09]Guarino,N. “Introduc8on toOntological Analysis”, Lecture notes for aPhDcoursegivenattheUniversityofTrento,May2009.[Hohfeld13] Hohfeld, N., “Fundamental Legal Concep8ons as Applied in JudicialReasoning”.Yale Law Journal 23(1),1913.[Mylopoulos97] Mylopoulos, J., “Informa8on Modeling in the Time of theRevolu8on”,Informa@on Systems 23(3‐4),June1998,127‐156.[Panofsky55] Panofsky, E., “Iconography and Iconology: An Introduc8on into theStudyofRenaissanceArt”,inMeaning in the Visual Arts.Doubleday,1955.[Schmidt09] Schmidt, J., “On Conceptual Content Management: InterdisciplinaryInsights beyond Computa8onal Data”, in Borgida, A., et al (eds.) Conceptual Modeling: Founda@ons and Applica@ons SpringerLNCSno.5600,June2009,153‐172.
References