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Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

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Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation
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Page 1: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Knowledge Acquisition and modelling

Introduction to Knowledge Acquisition and Elicitation

Page 2: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

DIKW (Data, Information, Knowledge, Wisdom) Pyramid Hierarchy Framework Continuum

Page 3: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Data, Information, Knowledge, Wisdom Data...

is raw. simply exists and has no significance beyond its

existence (in and of itself). It is raining

Information data that has been given meaning by way of

relational connection. "meaning" can be useful, but does not have to be.

The temperature dropped 15 degrees and then it started raining.

Page 4: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Data, Information, Knowledge, Wisdom Knowledge

the appropriate collection of information, such that it's intent is to be useful. If the humidity is very high and the temperature drops

substantially the atmospheres is often unlikely to be able to hold the moisture so it rains.

“Knowledge is a fluid mix of framed experience, values, contextual information, expert insight and grounded intuition that provides an environment and framework for evaluating and incorporating new experiences and information. It originates and is applied in the minds of knowers. In organizations it often becomes embedded not only in documents and repositories but also in organizational routines, processes, practices and norm”  Wallace, Danny P. (2007).Knowledge Management: Historical

and Cross-Disciplinary Themes.

Page 5: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Data, Information, Knowledge, Wisdom Understanding...

Cognitive and analytical. Way you can take knowledge and synthesize new

knowledge from the previously held knowledge. Wisdom...

calls upon all the previous experience previous levels of consciousness upon special types of human programming (moral,

ethical codes, etc.). It rains because it rains.

Page 6: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Transition

Page 7: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Example I have a box. The box is 3' wide, 3' deep, and 6' high. The box is very heavy. The box has a door on the front of it. When I open the box it has food in it. It is colder inside the box than it is outside. You usually find the box in the kitchen. There is a smaller compartment inside the box with ice in

it. When you open the door the light comes on. When you move this box you usually find lots of dirt

underneath it. Junk has a real habit of collecting on top of this box. What is it?

Page 8: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Types of Knowledge Procedural

How to E.g. I Know How To Drive A Car Processes, Tasks, Activities And conditions under which tasks are performed And sequence of tasks

Conceptual I know that … About ways in which things (concepts) are related to

each other and their properties

Page 9: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Types of Knowledge Explicit

Knowledge at the forefront of a person’s brain Thought about in a deliberate, conscious way Concerned with basic tasks, basic relationships

between concepts, basic properties of concepts Not difficult to explain

Tacit Deep, embedded knowledge At the back of a person’s brain Built from experience rather than being taught Gain when practice Leads to activities which seem to require no

conscious thought at all

Page 10: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Types of Knowledge

How to Boil An Egg Simple task easily explained

How to tie a shoelace Requires demonstration with commentary

E=mc2 Simply relates concepts

The position of keys on a keyboard Most people know this sub-conciously but few conciously

Basic, Explicit Knowledge

Deep, Tacit Knowledge

Conceptual Knowledge

Procedural Knowledge How to boil an

egg

E=mc2

How to interview an

expert

The properties of knowledge

The position of keys on a keyboard

How to tie a shoelace

Taken from Knowledge Acquisition in Practice A Step By Step Guide, Millton, Springer-Verlag

Page 11: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Exercise Working in groups for 10 mins

Create a version of the previous slide with examples of your own

Page 12: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Knowledge Acquisition First need to determine what that knowledge

is the process of Knowledge Acquisition and Elicitation non-trivial process

The information is often locked away in the heads of people - domain experts

The experts themselves may not be aware of the implicit conceptual models that they use

Have to draw out and make explicit all the known knowns, unknown knowns, etc….

Page 13: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Example “There are known knowns.

These are things we know that we know. There are known unknowns. That is to say, there are things that we know we don't know. But there are also unknown unknowns. There are things we don't know we don't know.”

Donald Rumsfeld 2002 (US Secretary of Defense

2001 to 2006)

Page 14: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Knowledge Acquisition Capturing knowledge about a subject domain

From people And other sources Using this to create a store of knowledge Usable by many different applications, users and

benefits Does not have to be a database

Can be a knowledge web, ontology, knowledge document etc

Page 15: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Eliciting Knowledge Most knowledge is in the heads of people People have vast amounts of knowledge People have a lot of tacit knowledge They don't know all that they know and use Tacit knowledge is hard (impossible) to

describe People with knowledge in organisations are

usually very busy and valuable people Each person doesn't know everything

Page 16: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Difficulties of knowledge acquisition People find it difficult to

Express their knowledge in a manner fully comprehensible to the person who wishes to acquire it

Know exactly what the person wants Give the right level of detail Present ideas in a clear and logical order Explain all the jargon and terminology of the

subject domain Recall everything relevant to the project/topic at

hand Avoid drifting into talking about irrelevant things

Page 17: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Difficulties of knowledge acquisition Person attempting to acquire knowledge from

someone find it difficult to: Understand everything the person says Note down everything the person says Keep the person talking about relevant issues Maintain high level of concentration needed Check they have fully understood what has been

said

Page 18: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Difficulties of Knowledge Acquisition Arise due to human cognition and

communication Humans are good at communication and

performing complex activities Not good at communicating complex activities

to those not from the same subject areas

Page 19: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Knowledge Acquisition Bottleneck Nothing happens until knowledge is acquired Sources of knowledge are unreliable

Domain experts provide incomplete, even incorrect knowledge

Domain experts may not be able to articulate their knowledge

Knowledge bases are hard to build Computational knowledge representations are

complex Techniques

Limited range Ignorance

Page 20: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Knowledge Acquisition Bottleneck Narrow bandwidth.

Available channels convert organizational knowledge from its source (either experts, documents, or transactions) are relatively narrow.

Acquisition latency. Slow speed of acquisition is

frequently accompanied by a delay between the time when knowledge (or the underlying data) is created and when the acquired knowledge becomes available to be shared.

Knowledge inaccuracy. Experts make mistakes and

so do tools used to mine data and information.

Maintenance can introduce inaccuracies or inconsistencies into previously correct knowledge bases.

Maintenance trap. As knowledge base grows,

so does the requirement for maintenance.

Previous updates that were made with insufficient care and foresight accumulate and render future maintenance more difficult .

As summarised by Christian Wagner in his paper titled Breaking the Knowledge Acquisition Bottleneck Through Conversational Knowledge Management., 2006

Page 21: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Terminology - Knowledge Acquisition A Method of Learning

Aristole For our purposes

Elicitation Collection Analysis Modelling Validation

Of Knowledge for use in a project

Process of obtaining all data, information and knowledge to get a consistent view of a person solving a problem Identifying sources, vetting for quality, combining findings

Page 22: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Terminology - Knowledge Elicitation Sub-set of Acquisition Focuses on retrieving knowledge from humans

(usually experts) Lots of tacit

Page 23: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Terminology - Knowledge Codification Representing knowledge in some form

Model Rules Ontology Video Presentation etc

Page 24: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Terminology - Knowledge Capture Can be used instead of Acquisition or

Codification Generic term covering aspects of all three

previous terms

Page 25: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Terminology – Knowledge Engineering Feignbaum and McCorduck 1983 Integrating knowledge into a computer

system To solve problems that require extensive

human expertise Typically building a knowledge based system Shares a lot with software engineering

Feigenbaum, Edward A.; McCorduck, Pamela (1983), The fifth generation (1st

ed.), Reading, MA: Addison-Wesley

Page 26: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

© 2005 Prentice Hall, Decision Support Systems and Intelligent Systems, 7th Edition, Turban, Aronson, and Liang

Page 27: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

© 2005 Prentice Hall, Decision Support Systems and Intelligent Systems, 7th Edition, Turban, Aronson, and Liang

Knowledge Sources

Documented Written, viewed, sensory, behavior

Undocumented Memory

Acquired from Human senses Machines

Page 28: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

© 2005 Prentice Hall, Decision Support Systems and Intelligent Systems, 7th Edition, Turban, Aronson, and Liang

Knowledge Levels

Shallow Surface level Input-output

Deep Problem solving Difficult to collect, validate Interactions betwixt system components

Page 29: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

© 2005 Prentice Hall, Decision Support Systems and Intelligent Systems, 7th Edition, Turban, Aronson, and Liang

Knowledge Categories

Declarative Descriptive representation

Procedural How things work under different circumstances How to use declarative knowledge

Problem solving Metaknowledge

Knowledge about knowledge

Page 30: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

© 2005 Prentice Hall, Decision Support Systems and Intelligent Systems, 7th Edition, Turban, Aronson, and Liang

Knowledge Engineers Professionals who elicit knowledge from

experts Empathetic, patient Broad range of understanding, capabilities

Integrate knowledge from various sources Creates and edits code Operates tools

Build knowledge base Validates information Trains users

Page 31: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

© 2005 Prentice Hall, Decision Support Systems and Intelligent Systems, 7th Edition, Turban, Aronson, and Liang

Page 32: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Problem type Description

Diagnosis Inferring malfunctions of an object from its behaviour andrecommending solutions.

Selection Recommending the best option from a list of possiblealternatives.

Prediction Predicting the future behaviour of an object from itsbehaviour in the past.

Classification Assigning an object to one of the defined classes.

Clustering Dividing a heterogeneous group of objects intohomogeneous subgroups.

Optimisation Improving the quality of solutions until an optimal one isfound.

Control Governing the behaviour of an object to meet specifiedrequirements in real-time.

Typical problems addressed

Page 33: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Example Algorithm - a strategy, consisting of a series of

steps, guaranteed to find the solution to a problem, if there is a solution.

Example: How do you find the area of a triangular board,

standing up vertically with one edge on the ground? Measure the length of the edge on the ground,

multiply it by the vertical height, and divide by two. The answer will be exactly right, every time. Which makes it an algorithm

Page 34: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Example Heuristic - a strategy to find the solution to a

problem which is not guaranteed to work. One sort of heuristic usually gives you the right

answer but sometimes gives you the wrong answer Another sort gives you an answer which isn’t 100%

accurate. Example:

How old are you? Subtract the year you were born in from 2012. The answer will either be exactly right, or one year

short. Which makes it a heuristic.

Page 35: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Knowledge Systems Analysis and Design Davis’ law: “For every tool there is a task perfectly suited

to it”.

But…

It would be too optimistic to assume that for every task there is a tool perfectly suited to it.

Page 36: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Knowledge Acquisition – Why a Collaborative Process ?

Knowledge engineer Domain expert

Logic Try to identify global

solutions, which are appropriate and can be made legitimate for all possible contexts.

Aim at obtaining knowledge models which are transparent, objective, and which consider a finite number of factors.

Logic Usually oriented towards

the individual case of their daily working processes, e.g. the individual patients.

Knowledge optimized for solutions that are appropriate for the given situation.

Try to consider as many factors as possible and are tolerant against inconsistencies.

KEY DIFFERENCE between knowledge-based systems and other types of software

Page 37: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Knowledge Acquisition – Why a Collaborative Process ? Complex and highly

specialized domains E.g. medicine

Characterized by a distribution of knowledge between domain experts.

Different experts – even from one and the same discipline – will have their own personal preferences and mental models.

E.g. Specialists for anesthesiology will rarely presume to build knowledge models for cardiac surgery.

Different perspectives improve the quality of the

resulting systems, so ensure that the systems will

meet the requirements from different user groups, especially from both the technical and the application domain.

Domain experts must ensure that the system will be accepted and trusted by their peers. E.g will a conservative user

group of medical doctors reject a clinical decision-support system which is solely designed from an engineer’s perspective?

Page 38: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Knowledge Acquisition – Why a Collaborative Process? “Knowledge is commonly socially constructed,

through collaborative efforts toward shared objectives or by dialogues and challenges brought about by differences in persons’ perspectives.”

Gavriel Salomon, Distributed Cognitions: Psychologicaland Educational Considerations. Cambridge University Press,

1993 Knowledge modeling must be heavily based on

communication and will usually require compromises. Models are “negotiated in a social relationship”

Rammert, Relations that constitute technology And media that make a difference: Toward a social pragmatic theory,

1999 Of technicizatio negotiation is often difficult

KEY POINTExperience shows that the bottleneck of building knowledge systems lies more in the social process than in the technology.

Page 39: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Human Cognition- Bernd Schmidt Human cognition and scientific theory construction -

iterative processes Cognition

based on the construction of theoretical models exposed to experimental data from real or simulated worlds.

=> Human cognition is driven by feedback. Theories must be validated or updated if new observations

are made. Experimental acquisition of case data is essential in

many scientific disciplines choice of experiments and the construction of simulation

models has an impact on the resulting theoretical models.

Page 40: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Knowledge Acquisition – Why an Evolutionary Process? Acquisition as a kind of theory construction Human experts have to construct formal theories about

the domain Backed by knowledge

either resides informally in their heads or can be acquired from some other knowledge source.

Resulting knowledge model is part of a knowledge-based system which can operate in real or simulated worlds.

Tests in both worlds produce feedback which allows the domain expert to revise the knowledge models.

When installed in the real application scenario, the system even changes the real world and thus produces new requirements, which recursively suggest changes to the knowledge model.

Page 41: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Knowledge Acquisition – Why an Evolutionary Process? We do not understand how humans carry out

reasoning tasks Makes it difficult to set out a detailed specification for

artefact to imitate humans Potential users are often unable to assess the

benefits or usage scenarios of the new system especially when they are inexperienced computer users.

Artefact modifies the work processes in which it is installed. Users modify their environment and their use of the

system New working culture emerges. Changes requirements => knowledge models must be

updated.

Page 42: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Knowledge Acquisition – Why an Evolutionary Process? Process cannot be completely planned

Different and unknown cognitive and social perspectives.

Hard to predict Often based on incorrect assumptions.

Domain experts required to transparently expose their daily practice but this “practice necessarily operates with deception”

Every artefact resulting is only an approximation of reality and the actors involved in the process speak different “languages”.

Page 43: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Knowledge Acquisition – Why an Evolutionary Process ? Knowledge is inherently complex and vague.

especially in non-deterministic domains e.g. medicine

Computers require formal data structures, which can be evaluared e.g. threshold values of patient observables. Experts tend to use trial-and-error methods to

determine such thresholds, until the system exposes the expected behavior.

Cannot predict progress which may change beliefs in KB

Page 44: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Knowledge Acquisition – Why an Evolutionary Process ? Knowledge modeling process itself produces

new knowledge. Self-observation performed during analysis of the

existing work processes can lead to new insights Knowledge is being translated and reorganized =>

evolves in the process of being encoded and formatted for the system

Existing work processes are challenged when analyzed – can lead to redesign during acquisition

Installation of knowledge-based systems may require “digitization” of the data flow in the process. E.g. installing a neural network, addition of a database,

creation of a data warehouse

Page 45: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Knowledge Acquisition – Why an Evolutionary Process ? Knowledge can not be mined and

processed like a raw material, but rather comes into existence during the communication

Communication will influence the resulting artefacts.

Process is characterized by reciprocities between engineers and experts

Information provided by the expert depends on the context.

As a domain expert gets more and more used to the formal view of the knowledge engineer, he/she will adjust her style, and vice-versa.

Page 46: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Personal Construct Theory (George Kelly) Theory that gives an account of how people experience

the world and make sense of that experience. ‘Person as a scientist’ Emphasises human  capacity for meaning making,

agency, and ongoing revision of personal systems of knowing across time

Individuals are seen as creatively formulating hypotheses about the areas of their lives, in an attempt to make them understandable or predictable.

Predictability is sought as a guide to practical action in concrete contexts and relationships.

People engage in continuous extension, refinement, and revision of their systems of meaning Moving systems towards increased meaning

Page 47: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Personal Construct Theory (PCT) Key Idea

the world is 'perceived' by a person in terms of whatever 'meaning' that person applies to it

and the person has the freedom to choose a different 'meaning' of whatever he or she wants.

i.e. the person has the 'freedom to choose' the meaning that one prefers or likes.

Alternative constructivism the person is capable of applying alternative

constructions (meanings) to any events in the past, present or future.

Page 48: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

PCT – Alternative Constructivism We assume that all of our present interpretations of

the universe are subject to revision or replacement... There are always some alternative constructions available to choose among in dealing with the world. => reality does not reveal itself to us directly, but can be

construed in a variety of ways. Constructs are the way in which things or people are

either similar or different. =>simultaneously differentiates and integrates.

To construe is both to abstract from past events, and provide a reference axis for anticipating future events based on that abstraction.

Kelly's notion of a personal scientist assumes that all people actively seek to predict and control events by forming relevant hypotheses, and then testing them against their experience.

Page 49: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

PCT Within man-the-scientist model,

the individual creates his or her own ways of seeing the world in which (s)he lives;

the world does not create them for him; (s)he builds constructs and tries them on for size; the constructs are sometimes organized into systems

groups of constructs which embody subordinate and superordinate relationships;

the same events can often be viewed in the light of two or more systems, yet the events do not belong to any system; and

the individual's practical systems have particular foci and limited ranges of convenience.

Page 50: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

PCT Assumes a contrast between individual reality,

social reality and shared reality: Individuality: "persons differ from each other in their

construction of events." Communality: "to the extent one person employs a

construction of experience which is similar to that employed by another, his psychological processes are similar to those of the other person."

Socialty: "to the extent that one person construes the construction processes of another, he may play a role in a social process involving the other person."

Over the last 50 years, the theory has found its home in the areas of artificial intelligence, education, human computer interaction, and human learning.

Page 51: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Newell and Simon’s Human Problem Solving Problem space

A person’s internal (mental) representation of a problem, and the place where problem-solving activity takes place.

Model known as performance model

Represents the problem solving behavior of one person who is performing a specific task, but are not adequate for system development since they are constrained to a single performer on a single task.

Seen as consisting of knowledge states, and problem solving proceeds by a selective search within the problem space, according to Newell and Simon using rules of thumb (heuristics) to guide the search.

Task environment The physical and social

environment in which problem solving takes place.

Situations which do not influence individual behavior can be studied by only analyzing the task environment.

Model known as the task model

Page 52: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Newell and Simon’s Human Problem Solving Both task and performance models are

required to enable problem solving behavior to be adequately modeled within a specific domain.

Unstructured environments are open for individual behavior, well-structured environments encourage common behavior.

Page 53: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Bias What is bias?

All views of reality are filtered. Bias only exists in relation to some reference point.

Types of bias: Motivational bias

expert makes accommodations to please the interviewer or some other audience

Observational bias Limitations on our ability to accurately observe the world

Cognitive bias Mistakes in use of statistics, estimation, memory, etc.

Notational bias Terms used to describe a problem may affect our

understanding of it

Page 54: Knowledge Acquisition and modelling Introduction to Knowledge Acquisition and Elicitation.

Examples Social pressure

response to verbal and non-verbal cues from interviewer

Group think response to reactions of

other experts Impression management

response to imagined reactions of managers, clients,…

Wishful thinking response to hopes or

possible gains Appropriation

selective interpretation to support current beliefs

Misrepresentation expert cannot accurately fit

a response into the requested response mode

Anchoring contradictory data ignored

once initial solution is available

Inconsistency assumptions made earlier

are forgotten Availability

some data are easier to recall than others

Underestimation of uncertainty tendency to underestimate

by a factor of 2 or 3


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