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Knowledge Acquisition and Modelling. Introduction. House Keeping. Contact Details deirdre.lawless@dit.ie 01 402 2869 Office KE-5-002 (fifth floor main building, first staircase access from main entrance) Take lift to 4 th floor Take stairs up to 5 th Floor
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Knowledge Acquisition and Modelling Introduction
House Keeping • Contact Details • deirdre.lawless@dit.ie • 01 402 2869 • Office • KE-5-002 (fifth floor main building, first staircase access from main entrance) • Take lift to 4th floor • Take stairs up to 5th Floor • Office is at the top of the stairs on your left. • Class contact • 3 hours per week for 12 weeks plus 1 review week (3 hours)
House Keeping • Home Page • http://www.comp.dit.ie/dlawless/kam.html
Broad Summary of Module • Knowledge • What is it? • What forms can it take? • Examples? • Storage? • Relationship to humans? • Relationship to artefacts? • Reliability? • Certainty? • Its Elicitation and Acquisition • How to? • Challenges? • Approaches? • Its Representation • Conceptual? • Functional? • Schemes? • Certainty?
Module Aim • To develop a foundation in the • key tools and technologies used in • knowledge acquisition, • modelling and • representation • To provide an opportunity for students to • gain practical experience of using these.
Learning Outcomes – What will you be able to do ? • Assess the main methodological and conceptual issues of knowledge acquisition; • Design, justify and implement an appropriate acquisition and elicitation strategy for a knowledge based problem; • Develop a conceptual knowledge model for a knowledge based problem;
Learning Outcomes – What will you be able to do ? • Examine the difficulty and complexity of knowledge representation; • Assess the appropriateness of a range of knowledge representation techniques for a knowledge based problem; • Formalise and represent knowledge using an appropriate knowledge representation technique;
Learning Outcomes • Employ appropriate uncertainty management techniques in the representation of a knowledge based problem; • Analyse a problem and identify the most appropriate knowledge representation, uncertainty management and reasoning approach to employ in solving it; • Use various computational tools to formalize and represent knowledge using uncertainty management.
Basics • Assessment • 50% assessment • Assessment broken into three parts • Deadline Wednesday December 5th@ 10.00 • 50% examination • Two hour exam • Compulsory Q1 • + Any other question • Lecture notes • Supplement to attending lectures • Available via class website • Reading Material • All reading material will be indicated as part of lecture notes
What do we already know? • What is knowledge ? • What does it mean to know something ?
What is Knowledge? • ‘Trivial Pursuit Model’ • Accepted absolutes • Common Knowledge • Mediated Knowledge • Unmediated Knowledge • What do you want to happen when you read an ‘encyclopedia’ or use a similar source?
What is knowledge? • Reliability • Knowledge is a true belief that has been arrived at by a reliable process • How reliable? • Is it possible to ever create the perfect encyclopedia? • If there was a perfect encyclopedia, could you get knowledge by reading it, understanding and believing it? • Who should create the perfect encyclopedia? • What is the role of experts? Expertise?
What is knowledge ? • Does not exist in a social vacuum • Kuhn’s Paradigm • The transition from a Ptolemaic cosmology to a Copernican one. • The transition between the worldview of Newtonian physics and the Einsteinian Relativistic worldview. • The development of Quantum mechanics, which redefined Classical mechanics. • The acceptance of Charles Darwin's theory of natural selection replaced Lamarckism as the mechanism for evolution.
What is knowledge? • All knowledge is the answer to a question that someone has posed • All knowledge began in doubt
Knowledge By Description (Russell) • Public knowledge • Knowledge of facts • Knowledge of a discipline • Describes the world using statements or propositions • Language and form of expression are crucial • Statements about reality are usually a combination of facts and interpretation
Knowledge by Description • Example • There has been an accident. A single observer (you) experiences the reality of the situation and communicates back to an audience. • You state: • ‘There are 12 people involved.’ • There are several built in assumptions that will determine if I believe you • you can see things for what they are, • the conditions of seeing are adequate • that you can describe them accurately • that you are a truth-teller • and that I can understand you • Overall the statement is thought to be objective • i.e. • Another person in a similar situation would report the same thing • However, details of the condition of the people involved is subjective or interpretative • Your opinions, feelings, experience will shape your statements • Knowledge By Description has as its goal more objective propositions but we recognise that most statements are a combination of fact and interpretation
Exercise • Which statements are more objective than interpretive? • 1 There was murder in his eyes. • 2 Four cars crashed together at the stop light. • 3 The sun is coming in the window. • 4 He was drunk when he hit the car. • 5 There were eight puppies in the kennel today. • 6 The fire drill rang at ten o’clock. • 7 No one was prepared to leave the school in an orderly way
Knowledge by Acquaintance (Russell) • Private knowledge • A felt knowledge, how to do something • May not be easily expressed but sense of certainty may be strong • Must convey your knowledge by acquaintance by descriptive knowledge • Best shown not explained
Rationalism v Empiricism • Rationalism (Descartes) • Reason has precedence over all other ways of acquiring knowledge • Empiricism (Locke) • Senses are primary with respect to knowledge
Exercise • Look at each of the propositions below and decide whether it can be proven true or false or both or • neither. Imagine that someone is asserting each one as knowledge, not merely believed or held as • an opinion. • 1 I know it is raining. • 2 I know it is raining or it isn’t raining. • 3 I know 2 + 2 = 4. • 4 I know two apples and two apples make four apples. • 5 I know my brother is my sibling. • 6 I know how to speak French. • 7 I know I will pass the test. • 8 I know girls are better at theory of knowledge than boys. • 9 I know murder is wrong. • 10 I know my tooth hurts. • 11 I know she doesn’t like me. • 12 I know God exists.
Answers • 1 • is empirical and needs sense experience to prove it true or false. • 2 • True under all conditions • once you have understood the language, • What could prove it false? • 3 • true at all times within the mathematical framework of base 10. • what could prove it false? • 4 • There is surface similarity to 3 but • This is an empirical statement about the physical world not maths • 5 • a rational proposition true by definition. • if he is your brother, then he is your sibling. • 6 • a ‘knowing how’ statement, not ‘knowing that. • Requires performance to proof • 7 • either true or false but, as such, it is not verifiable. • can a statement about the future be claimed to be true or false in advance of its occurrence? • 8 • could be classified as empirical since, in principle, it could be established as true or false by looking at all the evidence.
Exercise • 9 • Is this more of a belief? • 10 • Only true for you • No one else can verify it • 11 • Opinion or belief. How would you know? • 12 • ?
Exercise • What do you make of these propositions? Are they more rational or empirical? • Every event has a cause. • All people are created equal. • Whatever has shape has size. • Every cube has twelve edges. • I see with my eyes. • There is life on Mars.
The Correspondence Truth Test A statement is made about a state of affairs (facts) which either matches or doesn’t to the facts (state of affairs)
Coherence Truth Test Statements pass through their rational agreement with others
Pragmatic Truth Test • Based on believing something to be true rather than actual truth • Becomes interesting with beliefs
Exercise Which truth tests would you apply to test the truth of the following: 1 coherence (logical truths) 2 correspondence (observational truths) _______ a Metals expand when heated. _______ b It is raining. _______ c It is raining or it is not raining. _______ d A triangle has three sides. (The sum of the interior angles of a triangle = 180 degrees.) _______ e All white cats are white. _______ f All white cats are deaf. _______ g The population of Tokyo is larger than that of Hong Kong. _______ h All wives have husbands. _______ i Mars has no moons. _______ j Mars is a planet. _______ k The best team will win the World Series. _______ l If Bert is a younger son, then he is a brother. _______ m If Bert is a younger son, then he is a sibling. _______ n It is now raining in Rio. _______ o The hydrogen atom has one electron. _______ p You are either here or somewhere else. _______ q There is an invisible elephant in this room.