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Issues in Data Mining Infrastructure Authors: Nemanja Jovanovic, [email protected] Valentina Milenkovic, [email protected] Prof. Dr. Veljko Milutinovic, [email protected] http://galeb.etf.bg.ac.yu/~vm Page 1/71 Data Mining in the Nutshell Uncovering the hidden knowledge Huge n-p complete search space Multidimensional interface Page 2/71 A Problem … You are a marketing manager for a cellular phone company Problem: Churn is too high Turnover (after contract expires) is 40% Customers receive free phone (cost 125$) with contract You pay a sales commission of 250$ per contract Giving a new telephone to everyone whose contract is expiring is very expensive (as well as wasteful) Bringing back a customer after quitting is both difficult and expensive Page 3/71 … A Solution Three months before a contract expires, predict which customers will leave If you want to keep a customer that is predicted to churn, offer them a new phone The ones that are not predicted to churn need no attention If you don’t want to keep the customer, do nothing How can you predict future behavior? Tarot Cards? Magic Ball? Data Mining? Page 4/71 Still Skeptical? Page 5/71 The Definition The automated extraction of predictive information from (large) databases Automated Extraction Predictive Databases Page 6/71 History of Data Mining Page 7/71 Repetition in Solar Activity 1613 – Galileo Galilei 1859 – Heinrich Schwabe Page 8/71 The Return of the Halley Comet Edmund Halley (1656 - 1742) 1531 1607 1682 239 BC 1910 1986 Page 9/71 2061 ??? Data Mining is Not Data warehousing Ad-hoc query/reporting Online Analytical Processing (OLAP) Data visualization Page 10/71 Data Mining is Automated extraction of predictive information from various data sources Powerful technology with great potential to help users focus on the most important information stored in data warehouses or streamed through communication lines Page 11/71 Data Mining can Answer question that were too time consuming to resolve in the past Predict future trends and behaviors, allowing us to make proactive, knowledge driven decision Page 12/71 Focus of this Presentation Data Mining problem types Data Mining models and algorithms Efficient Data Mining Available software Page 13/71 Data Mining Problem Types Page 14/71 Data Mining Problem Types 6 types Often a combination solves the problem Page 15/71 Data Description and Summarization Aims at concise description of data characteristics Lower end of scale of problem types Provides the user an overview of the data structure Typically a sub goal Page 16/71 Segmentation Separates the data into interesting and meaningful subgroups or classes Manual or (semi)automatic A problem for itself or just a step in solving a problem Page 17/71 Classification Assumption: existence of objects with characteristics that belong to different classes Building classification models which assign correct labels in advance Exists in wide range of various application Segmentation can provide labels or restrict data sets Page 18/71 Concept Description Understandable description of concepts or classes Close connection to both segmentation and classification Similarity and differences to classification Page 19/71 Prediction (Regression) Finds the numerical value of the target attribute for unseen objects Similar to classification - difference: discrete becomes continuous Page 20/71 Dependency Analysis Finding the model that describes significant dependences between data items or events Prediction of value of a data item Special case: associations Page 21/71 Data Mining Models Page 22/71 Neural Networks Characterizes processed data with single numeric value Efficient modeling of large and complex problems Based on biological structures Neurons Network consists of neurons grouped into layers Page 23/71 Neuron Functionality I1 W1 I2 W2 I3 W3 In f Output Wn Output = f (W1*I1, W2*I1, …, Wn*In) Page 24/71 Training Neural Networks Page 25/71 Neural Networks - Conclusion Once trained, Neural Networks can efficiently estimate value of output variable for given input Neurons and network topology are essentials Usually used for prediction or regression problem types Difficult to understand Data pre-processing often required Page 26/71 Decision Trees A way of representing a series of rules that lead to a class or value Iterative splitting of data into discrete groups maximizing distance between them at each split Classification trees and regression trees Univariate splits and multivariate splits Unlimited growth and stopping rules CHAID, CHART, Quest, C5.0 Page 27/71 Decision Trees Balance>10 Age<=32 Married=NO Page 28/71 Balance<=10 Age>32 Married=YES Decision Trees Page 29/71 Rule Induction Method of deriving a set of rules to classify cases Creates independent rules that are unlikely to form a tree Rules may not cover all possible situations Rules may sometimes conflict in a prediction Page 30/71 Rule Induction If balance>100.000 then confidence=HIGH & weight=1.7 If balance>25.000 and status=married then confidence=HIGH & weight=2.3 If balance<40.000 then confidence=LOW & weight=1.9 Page 31/71 K-nearest Neighbor and Memory-Based Reasoning (MBR) Usage of knowledge of previously solved similar problems in solving the new problem Assigning the class to the group where most of the k-”neighbors” belong First step – finding the suitable measure for distance between attributes in the data How far is black from green? + Easy handling of non-standard data types - Huge models Page 32/71 K-nearest Neighbor and Memory-Based Reasoning (MBR) Page 33/71 Data Mining Models and Algorithms Many other available models and algorithms Logistic regression Discriminant analysis Generalized Adaptive Models (GAM) Genetic algorithms Etc… Many application specific variations of known models Final implementation usually involves several techniques Selection of solution that match best results Page 34/71 Efficient Data Mining Page 35/71 NO YES Is It Working? Don’t Mess With It! YES Did You Mess With It? You Shouldn’t Have! NO Anyone Else Knows? NO YES You’re in TROUBLE! NO Hide It Can You Blame Someone Else? YES NO PROBLEM! Page 36/71 YES Will it Explode In Your Hands? NO Look The Other Way DM Process Model 5A – used by SPSS Clementine (Assess, Access, Analyze, Act and Automate) SEMMA – used by SAS Enterprise Miner (Sample, Explore, Modify, Model and Assess) CRISP–DM – tends to become a standard Page 37/71 CRISP - DM CRoss-Industry Standard for DM Conceived in 1996 by three companies: Page 38/71 CRISP – DM methodology Four level breakdown of the CRISP-DM methodology: Phases Generic Tasks Specialized Tasks Process Instances Page 39/71 Mapping generic models to specialized models Analyze the specific context Remove any details not applicable to the context Add any details specific to the context Specialize generic context according to concrete characteristic of the context Possibly rename generic contents to provide more explicit meanings Page 40/71 Generalized and Specialized Cooking Preparing food on your own Raw Find out what youvegetables? want to eat stake with Find the recipe for that meal Check the Cookbook or call mom Gather the ingredients Defrost the meat (if you had it in the fridge) Prepare the meal Buy missing ingredients Enjoy yourthe food or borrow from the neighbors Clean up everything (or leave it for later) Cook the vegetables and fry the meat Enjoy your food or even more You were cooking so convince someone else to do the dishes Page 41/71 CRISP – DM model Business understanding Data understanding Data preparation Modeling Business understanding Deployment Evaluation Deployment Page 42/71 Evaluation Data understanding Data preparation Modeling Customizing a Web Page User-friendly design Prediction of the users interests Reduction of server workload Reduction of Web traffic Page 43/71 Customizing a Web Page Page 44/71 Business Understanding Determine business objectives Assess situation Determine data mining goals Produce project plan Page 45/71 Business Understanding - Outputs Background Business objectives and success criteria Inventory of resources Requirements, assumptions, and constrains Risks and contingencies Terminology Costs and benefits Data mining goals and success criteria Project plan Initial assessment of tools and techniques Page 46/71 Customizing a Web Page – Business Understanding Example Business objectives Make the users surfing Assess situation more comfortable Make the users Decrease of overhead surfingfor users Data mining goals more comfortable Reduction of workload and Find Web the Decrease traffic patterns of overhead for users Project planbehavior in the user Reduction of workload and Web traffic Page 47/71 Data Understanding Collect initial data Describe data Explore data Verify data quality Page 48/71 Data Understanding - Outputs Data collection report Data Background description of datareport List of data sources Data Detailed exploration descriptionreport of each data source For each data source, method of acquisition List of tables or other database objects Data Expected quality regularities report or patterns and Problems encountered in data acquisition methods of detection Description of each field units, codes, etc. Approach taken to assessincluding data quality Regularities or patterns found Results of data quality assessment (expected and unexpected) Any other surprises Conclusions for data transformation, data cleaning and any other pre-processing Conclusions related to data mining goals or business objectives Page 49/71 Customizing a Web Page – Data Understanding Example Collecting the data Update the server to monitor Data userdescription behavior Record the users activities Results of data exploring into a storage Analyze recorded data Decide which data is usable for mining Verification of the quality of the data Page 50/71 Data Preparation Select data Clean data Construct data Integrate data Format data Page 51/71 Data Preparation - Outputs Dataset description report Background including broad goals and plan for pre-processing Description of pre-processing Detailed description of resultant datasets Rational for inclusion/exclusion of attributes Discoveries made during pre-processing and implications for further work Dataset Page 52/71 Customizing a Web Page – Data Preparation Example Decide from what period will the users monitored actions be considered Make assumptions about unnecessary monitored data and discard them Classify user actions into categories, group interesting links, etc… If more information about user is available from other sources, use them Transform data into suitable forms so several modeling techniques could be applied Page 53/71 Modeling Select modeling technique Generate test design Build model Assess model Page 54/71 Modeling - Outputs Assessment of DM results with respect to business success criteria Test design Broaddescription description of the type of model and Model the training data to be used Type assessment of model and relation to data mining goals Model Explanation of how the model will be tested or assessed Overview assessment including Parameterofsettings used process to produce model Description of any for testing deviations from thedata testrequired plan Detailed description of the model and Description of any planned of models Detailed assessment of the examination model any special features by domain or data experts Comments models by domaininorthe data experts Conclusionson regarding patterns data Insights into why a certain modeling technique and certain parameter setting lead to good/bad results Page 55/71 Customizing a Web Page – Modeling Example The problem is prediction of behavior Regression could be a good solution due to distinct nature of the data Create the software according to the project plan Observe the behavior of the software Tune the model after each evaluation phase if needed Page 56/71 Evaluation results = models + findings Evaluate results Review process Determine next steps Page 57/71 Evaluation - Outputs Assessment of DM results with respect to business success criteria Reviewof of process Business Objectives and Review List of possible actions Comparison between success criterion and DM results Business Success Criteria Conclusion about achievability of success criterion and suitability of data mining process Review of “Project Success” Are there new business objectives? Page 58/71 Customizing a Web Page – Evaluation Example Observe the model behavior at work Collect response from Beta testers Check user satisfaction Check server and network engagement Classify results Determine which parameter of the model should be changed Present new ideas and modifications Step back into previous phases as needed Page 59/71 Deployment Plan deployment Plan monitoring and maintenance Produce final report Review project Page 60/71 Deployment - Outputs Monitoring and maintenance plan Final Overview report of deployment results and indication which of results may require updating Summary of Business Understanding Description ofobjectives how updating be triggered (background, and will success criteria) Description how updating will be performed Summary ofof data mining process Summary of data mining results Summary of results evaluation Summary of deployment and maintenance plan Cost/benefit analysis Conclusions for the business Conclusions for future data mining Page 61/71 Customizing a Web Page – Deployment Example Make the feature available to all users Make plan for maintenance and user feedback Analyze costs and benefits Summarize the whole documentation Summarize network and server additional activity Collect the new ideas Award according to results Leave space for upgrade Page 62/71 At Last… Page 63/71 Available Software Page 64/71 Available Software Discussion of data mining vendors and software is not included into this slide set Page 65/71 Conclusions Page 66/71 WWW.NBA.COM Page 67/71 Se7en Page 68/71 CD – ROM Page 69/71 Credits Anne Stern, SPSS, Inc. Djuro Gluvajic, ITE, Denmark Obrad Milivojevic, PC PRO, Yugoslavia Page 70/71 References Bruha, I., ‘Data Mining, KDD and Knowledge Integration: Methodology and A case Study”, SSGRR 2000 Fayyad, U., Shapiro, P., Smyth, P., Uthurusamy, R., “Advances in Knowledge Discovery and Data Mining”, MIT Press, 1996 Glumour, C., Maddigan, D., Pregibon, D., Smyth, P., “Statistical Themes nad Lessons for Data Mining”, Data Mining And Knowledge Discovery 1, 11-28, 1997 Hecht-Nilsen, R., “Neurocomputing”, Addison-Wesley, 1990 Pyle, D., “Data Preparation for Data Mining”, Morgan Kaufman, 1999 galeb.etf.bg.ac.yu/~vm www.thearling.com www.crisp-dm.com www.twocrows.com www.sas.com/products/miner www.spss.com/clementine Page 71/71 The END Page 72/71