A Case-based Approach to Knowledge Sharing and Learning Massoud Moussavi Visiting Scientist Schlumberger Cambridge Research Mmoussavi@cambridge. scr. slb. com
Outline • • Knowledge Representation Learning Case-based Reasoning Applications: World Bank, Schlumberger, Knowledge-Based Institutions • Summary MM 3/17/2018
Problems to Solve • Excessive production down time due to water problems • Facilities can not handle water • Costs for water treating excessive • Can not meet water discharge regulations MM 3/17/2018
Information to Represent In India in the 1950 s, milk production could not keep pace with growing demand. Some milk vendors watered down the milk. Because there were many vendors, and brand names were not clearly established, vendors who did not dilute their milk could not command a premium and were squeezed out of the market. The result was an overall drop in milk quality. Enter the National Dairy Development Board that encouraged creation of dairy cooperatives … MM 3/17/2018
Knowledge Sharing • • Lessons Learned and Best Practices Can best practices be replicated? How general is a best practice? Contrary to popular wisdom, there are times when it pays to reinvent the wheel! • Local adaptation of a best practice amounts to reinventing the best practice in the new context. MM 3/17/2018
Learning • Two paradigms of learning: direct (passive) and indirect (active). • In the direct method the teacher transmits knowledge to the passive student. • In the indirect method, the student takes the active role of discovering knowledge. MM 3/17/2018
Active Learning • Education is not an affair of “telling” and being told, but an active constructive process. • Socratic teacher: a midwife to student’s learning experience • Transformation of the student into an active constructor and appropriator of knowledge. • Giving a man a fish only feeds him for a day while teaching him how to fish feeds him for a lifetime. MM 3/17/2018
Active Learning • Learning by doing is difficult to implement • How do you teach history by doing? • What does it mean to teach literature by doing? MM 3/17/2018
Main Issues How to represent and access information? How to share and transfer knowledge? MM 3/17/2018
Representation & Reasoning • The object of Knowledge Representation is to express knowledge in computer-tractable form. • A knowledge base (KB) is a set of representations of facts about the world. Each individual representation is called a sentence. • Facts: Socrates is a man. Man is mortal. Most birds fly. Oil companies produce more water than oil. MM 3/17/2018
Representation & Reasoning • Determining what follows from the KB, is the job of an Inference mechanism. • Entailment: An inference procedure can do one of two things: given a KB, it can generate new sentences that are entailed by KB. Or, given a KB and a sentence p, it can report if p is entailed by KB; KB |= p • The power of formal inference is that it can be used to derive valid conclusions even when the computer does not know the interpretations we are using. MM 3/17/2018
Knowledge and Action • Knowledge helps in taking actions. • If you want to go for a walk, knowing if it might rain is helpful in deciding to take an umbrella. • Actions have knowledge preconditions and knowledge effects. • The action of taking an umbrella has the precondition of knowing the weather condition and listening to the weather report sometimes has the effect of knowing if it might rain. MM 3/17/2018
Case-based Reasoning • In many “weak theory” domains such as medicine, law, and economics tasks are not algorithmic. • Knowledge about problems are inherently casebased and prior experience is essential. • Reasoning is not always based on a set of first principles. • One deals with a new situation by applying, remembering, and modifying prior experience. MM 3/17/2018
Case-based Reasoning (CBR) • Reasoning is not modelled as a process that draws conclusions by chaining together generalized rules. • Rather, new solutions are generated by retrieving the most relevant cases from a memory of specific prior episodes and adapting them to fit new situations. • Reasoning is based on remembering. MM 3/17/2018
Learning and CBR • A learner is interested in acquiring cases that helps him/her to compare and contrast various experiences. • To do this the learner needs to label different experiences. • This labelling process is referred to as indexing. MM 3/17/2018
What is a case? • A case typically consists of: The problem that describes the state of the world The solution to the problem The outcome when the solution was carried out. MM 3/17/2018
Case-based Reasoning • Once cases are identified and classified, the task is to select the right case that applies to the current situation. • The CBR approach is based on two principles: (a) similar problems have similar solutions; and (b) problems tend to recur. • A CBR system finds the most similar case for a particular situation. MM 3/17/2018
Case-based Reasoning • Two major functional parts to a case: its content and its context described by its indexes. • A case’s indexes are combinations of its important descriptors. • Indexes are used for retrieval. MM 3/17/2018
An Example • Situation: You want to rent a video. How do you go about finding a film? • Films represented as cases. • Indexes: director, actors, cinematographer, theme, genera, script writer, music score, special effects, release date, awards, etc. • Knowledge navigation by using the absolute features. MM 3/17/2018
Search and Navigation by example • Alternatively you may want something like The English Patient that you last saw and liked. • Some alternatives: • The Talented Mr. Ripley, Shakespeare in Love • Life is Beautiful , The Sheltering Sky • The Unbearable Lightness of Being • Four Weddings and a Funeral, Angels and Insects MM 3/17/2018
The Example • Knowledge navigation through examples allows search even when the user is not familiar with the vocabulary of features. • The search criteria can be modified: “Life is Beautiful sounds good but don’t want another war story. ” • This applies to other domains as well: • The CV looks good but give me someone with more management experience. MM 3/17/2018
Case-based problem solving • Situation assessment maps an input problem to a set of indices describing the problem. • Retrieval searches for the case with the most similar problem description. • Adaptation transforms the solution of the most similar problem into one that fits new circumstances. MM 3/17/2018
Applications of CBR • World Bank as a knowledge-based Institution • Development assistance via knowledge sharing • A case-based prototype system for the World Bank MM 3/17/2018
What does the World Bank do? r r MM 3/17/2018 Invests in Economic and Social Development Projects to reduce poverty and improve living standards. Offers advice and an array of customized resources to developing countries.
Development Knowledge in terms of Cases o Knowledge about economic and social development is inherently case-based. o The experience of development projects can be related via cases. MM 3/17/2018
An Example: India’s Milk Market Problem Description In India in the 1950 s, milk production could not keep pace with growing demand. Some milk vendors watered down the milk. Because there were many vendors, and brand names were not clearly established, vendors who did not dilute their milk could not command a premium and were squeezed out of the market. The result was an overall drop in milk quality. MM 3/17/2018
An Example: India’s Milk Market Solution The National Dairy Development Board in the early 1970’s launched a multifaceted program that achieved the following: MM 3/17/2018 · encouraged the creation of dairy cooperatives. · rewarded quality through a pricing scheme. · established brand names. · created incentives for producing quality milk.
An Example: India’s Milk Market Outcome · By 1979 the incomes of a million milk producers had doubled. · India became the world’s third-largest producer of milk. · Quality of milk was improved. MM 3/17/2018
Indexing q In information retrieval systems the indexing is tied to the words of the text. q In case-based systems indexing is focused on the meaning of the text -- conceptual indexing. MM 3/17/2018
India’s Milk Market Feature-Value Based Indexes Sector = Agriculture Country = India Dealing with fraud State Intervention State subsidy Product: Milk (dairy) Village and small farmers Defining standards/regulation Monitoring/verifying quality Actors: State, Consumers, Vendors, Farmers, Distributors, Cooperatives Other features: brand names, etc. MM 3/17/2018
Questions-Based Indexing / How did India become one of the World’s largest producer of milk ? / What are the best ways to deal with fraud? / How do modern economies deal with verification and enforcement problem? / How do brand names provide quality assurance? / What are other top milk producing countries? / Why did the state intervene in the case of milk production in India? /What kinds of problems does government regulation MM create? 3/17/2018
Categories of Questions Research (ASK systems) on developing question templates: q Topic Elaboration: specifics and context q Explanation: causes and results Comparison: analogies and alternatives Application: opportunities and alternatives q q MM 3/17/2018
A Conversational System User Input Case Library Situation Assessment User Interface Knowledge Base MM 3/17/2018 Retrieved Case
Ordering and Selection of Cases for Learning purposes • • Some maxims (due to Roger Schank): No case before its time Cases should relate to actions Case should have the potential to change behaviour • Each case must address some expectation raised in a prior case. MM 3/17/2018
Problems & Challenges • • Indexing a difficult and laborious task. Selection of the right content and cases Semi-automated indexing Document summarization MM 3/17/2018
Summary • Representation of knowledge in terms of cases • Better user interfaces • Improved quality of learning MM 3/17/2018
How do modern economies deal with verification and enforcement problem? As economies develop, they find various ways of verifying quality. In many markets a variety of forms of certification evolve, from guild membership to membership in stock exchanges. As a complement to these private develop, they find various ways of reducing the problems of verifying efforts, government action is often required. For example, brand names may be an important way of producing quality assurance. They may also impose disclosure requirements—for example, requiring manufacturer of food products to disclose their ingredients. MM 3/17/2018
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