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anatés 2004 © Björn Nilsson anatés 2004 On modelling When it works and when it doesn't Why this talk..and why me? The Cartwright detector The canvas of.

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Presentation on theme: "anatés 2004 © Björn Nilsson anatés 2004 On modelling When it works and when it doesn't Why this talk..and why me? The Cartwright detector The canvas of."— Presentation transcript:

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2 anatés 2004 © Björn Nilsson anatés 2004 On modelling When it works and when it doesn't Why this talk..and why me? The Cartwright detector The canvas of modelling Cultures in collision ? Problem areas Academic focus Practitioners focus What works Some loose ends I have promised not to sing a bad rap text this time 1

3 anatés 2004 © Björn Nilsson anatés 2004 On usage of the material in this set of slides: The slides may be freely used in non-commercial education if reference is made to the author and CAiSE 2004 on each slide used and if no alterations are made. If slides or parts thereof are to be used in publications, please contact the author before publication as copyright problems may occur with respect to third parties. 2

4 anatés 2004 © Björn Nilsson anatés 2004 The Cartwright UFO detector According to a large number of reported incidents, the drive mechanism of some UFOs generate strong magnetic fields – strong enough to saturate the electric systems of a car and rattle nearby metal objects. …for some reason, this reminds me of a specific research area …. producing a lot of doctors …not reality based problems …elaborate hypotheses …simple verification …no validation 3

5 anatés 2004 © Björn Nilsson anatés 2004 The effect of modelling instruments A very rough value chain A scientifically based, reasonably efficient platform for modelling in terms of concepts, formalisms, working procedures etc. haven't already the consultancy comp. taken over PA Academia your output is here modelling analysis design change process ”business” process S PM P your value is here we want... 4

6 anatés 2004 © Björn Nilsson anatés 2004 The flower of modelling some important impact areas 40 60...a critical resource... 20 80 20 5

7 anatés 2004 © Björn Nilsson anatés 2004 The environment The customer The business operation The information system The infra structure demands sets the scenario value and cost demands value and cost demands value and cost The territory of modelling...x-axis seamless requirement propagation major levels of concern (simplified) …looks nice, but this is only one dimension 6 Key to success 1: Mirror the business and customer processes

8 anatés 2004 © Björn Nilsson anatés 2004 Analyse diagnosis Design solution Implement dev / strategy Environment Market / Customer Business op:s Info system (IT) Establish deploy / scrap Infrastructure (IT) Start configuration template Operate control The territory of modelling x+y+z axis Vision evolution / goals Action (use verb-phrase) Target if you are clever...the same model architecture may be used everywhere several frameworks on the market in this architecture, classes of services link the levels 7

9 anatés 2004 © Björn Nilsson anatés 2004 Problem areas Academia Reality Problem Workables What I experience as problems in practice tried approaches or research topics Bias in viewpoints (disregarding variety and etiquette) Within the ”Modelling community” 8

10 anatés 2004 © Björn Nilsson anatés 2004 Interpretation guidelines The assertions on are made in a very generalising way, sometimes a bit provocative The assertions are to be interpreted as the – not allways conscious – bias or undercurrent that effects our thoughts and behaviour. No corrections are made for the enormous personal and institutional variety out there The assertions are not deeply analysed – that would require a weeks discussion or so... 9

11 anatés 2004 © Björn Nilsson anatés 2004 observations on Value system Ego General culture Basic world-view Scientific approach Scale of problems Communication culture Communication theories Development process Design drivers (micro) Blind spots Model assesment Group dynamics Formalismic emphasis Preferred graphics Gestalt of graphical results Model LCM / interoperability System views Methods deployment AcademiaPractice

12 anatés 2004 © Björn Nilsson anatés 2004 Value system Efficiency and other criteria are lacking Instruments to handle large scale model evolution are not adequate Consistency Logic Quality driven Trend driven Unresponsible Completeness AcademiaPractice Workables Usefulness Effect driven ROI Trend driven Long time responsibility ”Completeness” has destroyed many projects 11

13 anatés 2004 © Björn Nilsson anatés 2004 Ego hmmmm…. looks like a simple The lone hero My result / part of the result Personal contribution as the basis for academic career Personal recogition AcademiaPractice Workables The team The result If you scratch beneath the surface: Lurking ”Messiah” complex Power (external business culture) 12

14 anatés 2004 © Björn Nilsson anatés 2004 General culture Most useful (business level) analysis methods are to be found in other disciplines Syntax culture Analysis culture Model of something Single perspective (getting one view right) AcademiaPractice Workables Semantics culture Design culture Model for something Architecture (getting many perspectives into phase) Often ”model for the reason of modelling” or to illustrate principles Many practitioners also confuse analysis with making a picture of Too little diagnosis 13

15 anatés 2004 © Björn Nilsson anatés 2004 Basic world-view Often, social constructivism is a critical success factor: The question to ask in modelling is: What is the most practical way of looking at this phenomenon? How things really are, leads to disaster Naive realism Yes, yes, I understand that you are much more sophisticated AcademiaPractice Workables Social constructivism 14

16 anatés 2004 © Björn Nilsson anatés 2004 Scientific approach Practice has, to some extent, been myth driven, lacking sound instruments and verified methods IS-tool driven approaches with bad side effects Positivistic... Grounded theory.... Axiomatic Validation rare Complex theory Academia Practice Workables Commercial methods Folklore Politics Validation normal Oversimplification A scientifically based, reasonably efficient platform for modelling in terms of concepts, formalisms, working procedures etc. PA Academia analysis design change process enterprise process S PM P Clean, nice, toy problems – often tailored to suit the solution. Hairy, ugly, money related problems – often with no ”right” solution...this may make the value added rather limited.. 15

17 anatés 2004 © Björn Nilsson anatés 2004 Scale of problems Non scaleable solutions The quantitative differences are so big that they become a qualitative matter 7 + 3 classes 7 + 3 processes One + author over a couple of months ”Consistency” with previous work AcademiaPractice Workables 450 classes 200 processes 5 groups à 10 persons 2 days every 2 weeks for 18 months Legacy horrors with complex system interaction – the value is in the information, not the ”systems” _ _ 16

18 anatés 2004 © Björn Nilsson anatés 2004 Communication culture We pray and hope that model based development will change this However, this needs architectures, method coalisions over traditional professional boundaries Closed Necessary synergy between disciplines is not achieved AcademiaPractice Workables Closed Management/business development and IT- development do not communicate well 17

19 anatés 2004 © Björn Nilsson anatés 2004 Communication theories Theories are not well known Much useful material from linguistics, semiotics, philosophy Sophisticated AcademiaPractice Workables MMI-standards In three cases, with myself involved, scientifically constructed interfaces have had to be replaced Think about MS standards in time critical applications… 18

20 anatés 2004 © Björn Nilsson anatés 2004 intention observation description concept world 19 respons action information model deviation information distorsion data distorsion representation model deviation Human communication via IT-systems data base domain information domain data domain “mental model” deviation concept world description effect domain

21 anatés 2004 © Björn Nilsson anatés 2004...a brittish soldier may formulate it as... ”I see a shabby T74 closing in on our house” Moving fast for the anti tank missile launcher, his companion might reply ”We just might help him out with some of our surplus olive green paint” The natural language has a surface and a deep structure....and we may ask for clarification.... In IT-based systems, the information model is the basis for interpretation of received sentences. 20

22 anatés 2004 © Björn Nilsson anatés 2004 Development process As the output of the academic society is open, the learning process is fast. This is not the case for the practitioner. Networks are quickly growing in the modelling community. Iterative Incremental Formalizeable problem first Trend-oriented problem first AcademiaPractice Workables Iterative Incremental Toughest problem first (feasibility) Scientific paradigms vary a lot Methods vary a lot but converge towards UP...with positive and negative effects. Market: International. 21

23 anatés 2004 © Björn Nilsson anatés 2004 Design driver (micro) In a complex environment, the effects are very similar to what happens when you give a saw to a seven year old boy and let him loose in your house Object class AcademiaPractice Workables Use case –volume –unknown coverage Use cases sometimes work in controlled simple cases like banking, flight reservation and Coke- machines. 22

24 anatés 2004 © Björn Nilsson anatés 2004 Management by objectives Management by procedure Management by resources Management by rules Humanistically based multiple design drivers …management perspectives same as model perspectives resources will constraints 23

25 anatés 2004 © Björn Nilsson anatés 2004 …what about the IS... Business processes Business goals Business rules Business resources (objects ) Business interaction Modelling perspectives of the business operation …expressed in simplified model types... 24

26 anatés 2004 © Björn Nilsson anatés 2004 …so…structurally, the use case fits Modelling perspectives of the business operation Modelling perspectives of the info- system Business processes Business rules Business resources objects Info system processes Business interaction req:ts. System services Info system rules Info system objects Business goals proc. / control objects manipulation / view objects narrow sense business objects transform 25 …aha... levels of classes of services …aha... In terms of business services

27 anatés 2004 © Björn Nilsson anatés 2004 processes rulesobjects processes goals rulesobjects requirements services interface Value transfer 26 its all a question about requirements meeting services – over (more or less) well defined interfaces. 26 …but why does not the use case work on the business level...

28 anatés 2004 © Björn Nilsson anatés 2004 Example: I have just been asked to assist a small project 120 use cases on the business level no control of if this covers the whole problem 20 pages per unfinished use case no referential control Use use-cases when they are useful Assembly Line Diagram i UML Business Extensions Process LA Process LB Object class (information) modelling classical system service types use cases are often OK …it all hangs together via the classes 27

29 anatés 2004 © Björn Nilsson anatés 2004 By the way.... Even if use-cases are fairly unsuitable for complex analysis of requirements, especially on the business level - especially, if they are seen as THE instrument, they are excellent as test material, when using the sequences (sequence diagrams / user stories) for partial verification 28

30 anatés 2004 © Björn Nilsson anatés 2004 PnPn P n-1 Service interface Social Action Pragmatical Semantical Syntactical Empirical Physical Detection economy Value economy Culture economy Communication economy Information economy Storage / transport economy Encoding economy Björn Nilsson 1996 / 1998 / 2000 Satisfaction Effect economy …do not forget that communication puts demands on all semiotic levels.....is the kernel of business the interface ?? YES! 29

31 anatés 2004 © Björn Nilsson anatés 2004 Analysis of the environment Analysis of customers, mkt Analysis of the business Analysis of the business operation Bus proc Cust proc The business: Our total interaction with the market. The transactions and the effects thereof. In those terms, goals are expressed. Control: Our total interaction between processes. The message flow and its effects The means for controlling the activities achieving the goals Customer needs How we meet customer needs How we act to meet those needs A business definition English is a very weak language in this case as business proper and business operations (processes) go under the same word Scenario 30 IS proc How we control the action Björn Nilsson 1996 / 1998

32 anatés 2004 © Björn Nilsson anatés 2004 Blind spots Goal analysis, one of the most fundamental tasks we perform has virtually no methods support Requires high skill > 5 iterations to get good formulations Standard patterns and topologies help Goal analysis and design AcademiaPractice Workables Rule analysis and design Serious goal- / objective- analysis and design OK OK...some methods as morphological analysis.....but no real workable method Normally, a skilled analyst/designer has to make a lot of structural work and validation 31

33 anatés 2004 © Björn Nilsson anatés 2004 Model assesment Instruments for diagnosing models are lacking Very few skilled individuals on the market Case grammars quite useful for completeness control Logic AcademiaPractice Workables Built into the process Linguistic tools Parallell model walk throughs 32

34 anatés 2004 © Björn Nilsson anatés 2004 Group dynamics Methods are imported from other disciplines. Modelling is very special as, for instance, the graphics is an important control instrument for group activity Architectures and methods give direction Patterns for solutions give stability Neglected AcademiaPractice Workables Critical success factor 40% of advanced modelling coach education is about group handling and composition 33

35 anatés 2004 © Björn Nilsson anatés 2004 Formalismic emphasis We pay after how well the consultants deviate from the methods Hyper critical Semantics (meaning) in illustrations is often extremely vague AcademiaPractice Workables Fairly important During analysis, you will have to walk outside the boundaries and invent new forms Often ”model for the reason of modelling” or to illustrate principles Many practitioners confuse analysis with making a picture of Too little diagnosis 34

36 anatés 2004 © Björn Nilsson anatés 2004 Preferred graphics The OMG-published extensions marks a step forward Tools do not mix graph- types…. UML AcademiaPractice Workables UML UML business extension 35 Business extensions: –Goal analysis –Process with information usage –Desynchronisation

37 anatés 2004 © Björn Nilsson anatés 2004 Gestalt of graphical results Combine model types in one diagram.... Packageing Utterly simplistic Structural content Poor formalisms AcademiaPractice Workables Fairly complex Methaphorical content –50% cannot read the graphs Cognitive impact unknown Rich formalisms Mainly to illustrate principles Semantics unaffected by geometrical transformations The customer can not read the diagrams... The customer has not the stamina to read the text.... 36

38 anatés 2004 © Björn Nilsson anatés 2004..a walkthrough in a middle sized project... anatés Gestaltung 37

39 anatés 2004 © Björn Nilsson anatés 2004 Model LCM / interoperability Ex post facto model integration costs around 10 times as much as concurrent modelling with integration. Mechanisms to avoid it: –Core models –Continuous integration Yes, yes..... All modelling is model integration Model integration Big insight problem A lot of not very useful theory AcademiaPractice Workables Model integration Insight problem Core models (HUB) as instrument for continuous integration Was trendy once upon a time 400 + 50 200 + 200 38

40 anatés 2004 © Björn Nilsson anatés 2004...integration mainly by specialisation … …untranslated... 39

41 anatés 2004 © Björn Nilsson anatés 2004 A1 Data- model (Internal schema) Information model (Konceptual schema) Data exch. (MMI) model (External Schema) A2..the game is actually interoperability.... A3 Data exch. model (External Schema) 40 Data exch. model (External Schema) Information model (Konceptual schema) Data- model (Internal schema) Data exch. (MMI) model (External Schema) Semantic interoperability Syntactic interoperability A7 A6 A5 A6 A4

42 anatés 2004 © Björn Nilsson anatés 2004 Information- perspective (Meaning, content) Data- perspective (Representation, form) Information exchange model Concept model Information model Data model Storage model IE Data Model Message perspective (Meaning and form) …which require some info related models 41

43 anatés 2004 © Björn Nilsson anatés 2004 System view The situation is horrifying. The simple mechanisms to model are not known. Horror example: a Subsystem is a System The remedy is elem. education...often the general solution is cheaper to implement. Classic system theory with variants AcademiaPractice Workables Defined levels of systems Patents on four levels in telecom..... Software with: Process, Subprocess, Activity 42

44 anatés 2004 © Björn Nilsson anatés 2004 A fractal approach saves money 43 Vilka syften styr vårt arbete med modellering Vilka spel- regler har modellering Vad analyserar och utformar vi Hur genomförs modelleringarna 43

45 anatés 2004 © Björn Nilsson anatés 2004 Methods deployment Component based aproach Package as required by ”customer” Articles Conferences Education Much to do AcademiaPractice Workables Marketing Tools Education To correct what is done here 44

46 anatés 2004 © Björn Nilsson anatés 2004 What do we actually mean when we define cardinality / functionality ? One over time? One at any moment but many over time? Specific point in object life cycle? Over the whole life cycle (in the basic state transition model)? How things are? Our knowledge state? Small problems (trivialities) ???? …cost in an ongoing project. around 100 000 euro.. 45

47 anatés 2004 © Björn Nilsson anatés 2004 Queer semantics Actual expression: – Activitytype a produces Resourcetype b –(Very ugly!) Wanted meaning –an Activity of Activitytype a produces Resourses of Resourcetype b Loose ends 46

48 anatés 2004 © Björn Nilsson anatés 2004 Here, we broke the session! Thanks for your attention! I hope to have given you some seeds for thought.

49 anatés 2004 © Björn Nilsson anatés 2004 Warning to see interfaces as a transfer of requirements to the next phase of a project or to a new kind of competence. An interface is a mutual contract implying a shared responsibility to work it out …try to enforce seamless development... …transfer models have never worked, are not working and will never work... 48 Business competence in a wide sense IT competence in a wide sense Business The information system interface

50 anatés 2004 © Björn Nilsson anatés 2004 The company name anatés is based on two Swedish words ana lys (gr. analusis, decomposition) Study aiming at, from a whole discern its parts and explain existing relationships syn tés (gr. sunthesis, recomposition) Intellectual operation by which, within a domain, separate known elements are composed into a coherent, structured and homogenous whole the kernel of analysis is synthesis the kernel of synthesis is analysis 49


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