1 learning from data lecture ten (chapter 10, notes; chapter 11, textbook)
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Chapter 10: Learning From Data
OutlineOutline
The Concept of LearningThe Concept of Learning Data VisualizationData Visualization Neural NetworksNeural Networks
The BasicsThe BasicsSupervised and Unsupervised LearningSupervised and Unsupervised LearningBusiness ApplicationsBusiness Applications
Association RulesAssociation Rules Implications for Knowledge ManagementImplications for Knowledge Management
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Chapter 10: Learning From Data
The “Context” of The “Context” of LearningLearning
The “value added” The “value added” collaborative intelligence layer collaborative intelligence layer of of KM architectureKM architecture
Relevant technologies are:Relevant technologies are: Artificial IntelligenceArtificial Intelligence Experts SystemsExperts Systems Case-Based ReasoningCase-Based Reasoning Data WarehousingData Warehousing Intelligent agentsIntelligent agents Neural NetworksNeural Networks
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Chapter 10: Learning From Data
The “Process” of The “Process” of LearningLearning
A process of filtering and A process of filtering and transforming data into valid transforming data into valid and useful knowledge.and useful knowledge.
Automate via technology Automate via technology tools:tools: provide a collaborative provide a collaborative
learning environment for learning environment for participantsparticipants
enhance their ability to enhance their ability to understand the processes understand the processes / tasks they are dealing / tasks they are dealing withwith
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Chapter 10: Learning From Data
The “Goals” of LearningThe “Goals” of Learning
Final goal is to Final goal is to improve the improve the qualities of communication qualities of communication and decision makingand decision making
Ways to achieve these Ways to achieve these goals:goals: Verify hypotheses (formed Verify hypotheses (formed
from accumulated from accumulated knowledge)knowledge)
Discover new patterns in Discover new patterns in datadata
Predict future trends and Predict future trends and behaviourbehaviour
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Chapter 10: Learning From Data
Learning from DataLearning from Data
Build learning models that Build learning models that automatically improve with automatically improve with experience.experience.
Top-down approachTop-down approach Generate ideasGenerate ideas Develop modelsDevelop models Validate modelsValidate models
Bottom-up approachBottom-up approach Discover new (unknown) patternsDiscover new (unknown) patterns Find key relationships in dataFind key relationships in data
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Chapter 10: Learning From Data
Top-down approach Top-down approach (Example)(Example)
Start with a hypothesis Start with a hypothesis derived from observation or derived from observation or prior knowledgeprior knowledge
““Tourists visiting Egypt Tourists visiting Egypt earn an annual income of at earn an annual income of at least $50,000”least $50,000”
Hypothesis tested by Hypothesis tested by querying database followed querying database followed by analysisby analysis
If tests not supportive, If tests not supportive, hypothesis is revised and hypothesis is revised and test againtest again
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Chapter 10: Learning From Data
Bottom-up approach Bottom-up approach (Example)(Example)
No hypothesis to testNo hypothesis to test ““Find unknown buying Find unknown buying
patterns by analyzing patterns by analyzing the shopping basket”the shopping basket”
“ … “ … showed married showed married males, age 21 to 27, males, age 21 to 27, shopped for diapers shopped for diapers also brought beer.also brought beer.
““store decided to stack store decided to stack beer cases next to beer cases next to diaper shelf”diaper shelf”
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Chapter 10: Learning From Data
Data VisualizationData Visualization
Explore visually for trends Explore visually for trends in data useful for making in data useful for making decisiondecision
Exploring data includes:Exploring data includes: Identify key attributes Identify key attributes
and their distributionand their distribution Identify outliersIdentify outliers Extract interesting Extract interesting
grouping of data subsetsgrouping of data subsets Identify initial hypothesisIdentify initial hypothesis
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Chapter 10: Learning From Data
Example of Data Example of Data VisualizationVisualization
(John Snow and the Cholera outbreak in London, (John Snow and the Cholera outbreak in London, 1845)1845)
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Chapter 10: Learning From Data
Artificial Neural Artificial Neural Network as Learning Network as Learning
ModelModel Modeled after human Modeled after human
brain’s networkbrain’s network Simulate biological Simulate biological
information information processing via processing via networks of networks of interconnected interconnected neuronsneurons
Neural networks are Neural networks are analog and parallelanalog and parallel
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Chapter 10: Learning From Data
Neurons – The Basic Neurons – The Basic ElementsElements
The neuron receives The neuron receives inputsinputs, determines , determines their weights their weights (strengths), sums the (strengths), sums the combined inputs, and combined inputs, and compares the total to a compares the total to a thresholdthreshold ((transfer transfer functionfunction))
If total is greater than If total is greater than threshold, the neuron threshold, the neuron fires (sends an fires (sends an outputoutput) )
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Chapter 10: Learning From Data
Learning in Neural Learning in Neural NetworkNetwork
SupervisedSupervised The NN needs a The NN needs a
teacher with a teacher with a training set of training set of examples of input examples of input and outputand output
Unsupervised (or Unsupervised (or Self-Supervised)Self-Supervised) Does not need a Does not need a
teacherteacher
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Chapter 10: Learning From Data
Supervised LearningSupervised Learning
Each element in a Each element in a training set is paired training set is paired with an acceptable with an acceptable responseresponse
Network makes Network makes successive passes successive passes through the examples through the examples
The weights adjust The weights adjust toward the goal toward the goal state. state.
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Chapter 10: Learning From Data
A Supervised Neural A Supervised Neural Network (An Example)Network (An Example)
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Chapter 10: Learning From Data
Unsupervised LearningUnsupervised Learning
No external factors No external factors can influence can influence adjustment of input’s adjustment of input’s weightsweights
No advanced No advanced indication of correct indication of correct or incorrect answersor incorrect answers
Adjusts through Adjusts through direct confrontation direct confrontation with new experienceswith new experiences
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Chapter 10: Learning From Data
Business Applications Business Applications (1)(1)
Risk managementRisk management
Appraise commercial loan Appraise commercial loan applications applications
NN trained on thousands of NN trained on thousands of applications, half of which were applications, half of which were approved and the other half rejected approved and the other half rejected by the bank’s loan officersby the bank’s loan officers
Through supervised learning, NN Through supervised learning, NN learned to pick risks that constitute a learned to pick risks that constitute a bad loanbad loan
Identifies loan applicants who are Identifies loan applicants who are likely to default on their paymentslikely to default on their payments
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Chapter 10: Learning From Data
Business Applications (2)Business Applications (2)
Predicting Foreign Exchange Predicting Foreign Exchange Fluctuations:Fluctuations: A set of relevant indicators were A set of relevant indicators were
identified, used as inputs to NNidentified, used as inputs to NN NN was trained for exchange rates NN was trained for exchange rates
of US dollar against Swiss franc of US dollar against Swiss franc and Japanese yen, using data from and Japanese yen, using data from first 6 months of 1990. Then it was first 6 months of 1990. Then it was tested over an 8- to 11-week periodtested over an 8- to 11-week period
Results revealed return on capital Results revealed return on capital of about 20% of about 20%
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Chapter 10: Learning From Data
Business Applications (3)Business Applications (3)
Mortgage Appraisals:Mortgage Appraisals: Neural network uses the data in Neural network uses the data in
the mortgage loan application the mortgage loan application It estimates value of the property It estimates value of the property
based on the immediate based on the immediate neighborhood, the city, and the neighborhood, the city, and the countrycountry
The system comes up with a The system comes up with a valuation for the property and a valuation for the property and a risk analysis for the loan. risk analysis for the loan.
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Chapter 10: Learning From Data
Association RulesAssociation Rules
A KB tool that generates a A KB tool that generates a set of rules to help set of rules to help understanding understanding relationships that exist in relationships that exist in datadata
Types:Types: Boolean ruleBoolean rule Quantitative ruleQuantitative rule Multi-dimensional ruleMulti-dimensional rule Multi-level association Multi-level association
rulerule
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Chapter 10: Learning From Data
Boolean Rule (An Boolean Rule (An Example)Example)
A rule that examines the A rule that examines the presence or absence of presence or absence of itemsitems
For example, if a For example, if a customer buys a PC and a customer buys a PC and a 17” monitor, then he will 17” monitor, then he will buy a printer. Presence buy a printer. Presence of items (a PC and 17” of items (a PC and 17” monitor) implies presence monitor) implies presence of the printer in the of the printer in the customer’s buying listcustomer’s buying list
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Chapter 10: Learning From Data
Quantitative Rule (An Quantitative Rule (An Example)Example)
A rule that considers the A rule that considers the quantitative values of quantitative values of itemsitems
For example, if a For example, if a customer earns between customer earns between $30,000 and $50,000 $30,000 and $50,000 and owns an apartment and owns an apartment worth between $250,000 worth between $250,000 and $500,000, he will and $500,000, he will buy a 4-door automobilebuy a 4-door automobile
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Chapter 10: Learning From Data
Multi-dimensional RuleMulti-dimensional Rule
A rule that refers to a A rule that refers to a multitude of dimensionsmultitude of dimensions
If a customer lives in a If a customer lives in a big city and earns more big city and earns more than $35,000, then he than $35,000, then he will buy a cellular phonewill buy a cellular phone
This rule involves 3 This rule involves 3 attributes: attributes: living, living, earning, and buyingearning, and buying. . Therefore, it is a multi-Therefore, it is a multi-dimensional ruledimensional rule
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Chapter 10: Learning From Data
Implications for Implications for Knowledge Knowledge
ManagementManagement Cost / benefit analysisCost / benefit analysis
Tangible costs - user training, Tangible costs - user training, hardware + software, backup, hardware + software, backup, support, maintenancesupport, maintenance
Intangible costs - user resistance Intangible costs - user resistance and learning curveand learning curve
Quality AssuranceQuality Assurance Adequacy of initial designAdequacy of initial design Level and frequency of Level and frequency of
maintenancemaintenance
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Chapter 10: Learning From Data
User Interface(Web browser software installed on each user’s PC)
Authorized access control(e.g., security, passwords, firewalls, authentication)
Collaborative intelligence and filtering(intelligent agents, network mining, customization, personalization)
Knowledge-enabling applications(customized applications, skills directories, videoconferencing, decision support systems,
group decision support systems tools)
Transport(e-mail, Internet/Web site, TCP/IP protocol to manage traffic flow)
Middleware(specialized software for network management, security, etc.)
The Physical Layer(repositories, cables)
. . . . .
Databases Data warehousing(data cleansing,
data mining)
Groupware(document exchange,
collaboration)
Legacy applications(e.g., payroll)
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Layers of KM Layers of KM ArchitectureArchitecture