steps in the data mining process

29
Steps in the Data Mining Process João Gama [email protected] December, 2018

Upload: others

Post on 23-May-2022

3 views

Category:

Documents


0 download

TRANSCRIPT

Page 1: Steps in the Data Mining Process

Steps in the Data Mining Process

João Gama

[email protected]

December, 2018

Page 2: Steps in the Data Mining Process

Results of Data Mining Include:

• Forecasting what may happen in the future• Classifying people or things into groups by

recognizing patterns• Clustering people or things into groups based

on their attributes• Associating what events are likely to occur

together• Sequencing what events are likely to lead to

later events

Page 3: Steps in the Data Mining Process

Data mining is not–Brute-force crunching of bulk data –“Blind” application of algorithms–Going to find relationships where none exist

–Torturing Data Until They Confess–Presenting data in different ways–A database intensive task–A difficult to understand technology requiring an advanced degree in computer science

Page 4: Steps in the Data Mining Process

Data Mining Is•A hot buzzword for a class of techniques that find patterns in data

•A user-centric, interactive process which leverages analysis technologies and computing power

•A group of techniques that find relationships that have not previously been discovered

Page 5: Steps in the Data Mining Process

Data Mining versus OLAP

•OLAP - On-line Analytical Processing– Provides you with a very good

view of what is happening, – reporting– but can not predict what will

happen in the future or why it is happening

Page 6: Steps in the Data Mining Process

Predictive and Prescriptive Analytics

Page 7: Steps in the Data Mining Process

Predictive and Prescriptive Analytics

Page 8: Steps in the Data Mining Process

Predictive and Prescriptive Analytics

Page 9: Steps in the Data Mining Process

Methodologies for data mining

• 1997: Fayyad, Simoudis

• 2000: SEMMA – SAS

– Sample, Explore, Model, Modify, Assess

• 2000 - CRISP-DM,

– CRoss Industry Standard Process for Data Mining

Page 10: Steps in the Data Mining Process

The Data Mining ProcessFayyad & Simoudis (1997)

Page 11: Steps in the Data Mining Process

Phases of SEMMA (SAS)• Sample.

– The process starts with data sampling, e.g., selecting the data set for modeling. The data set should be large enough to contain sufficient information to retrieve, yet small enough to be used efficiently.

• Explore.

– This phase covers the understanding of the data by discovering anticipated and unanticipated relationships between the variables, and also abnormalities, with the help of data visualization.

• Modify.

– The Modify phase contains methods to select, create and transform variables in preparation for data modeling.

• Model.

– In the Model phase the focus is on applying various modeling (data mining) techniques on the prepared variables in order to create models that possibly provide the desired outcome.

• Assess.

– The last phase is Assess. The evaluation of the modeling results shows the reliability and usefulness of the created models.

Page 12: Steps in the Data Mining Process

SEMMA• SEMMA mainly focuses on the modeling tasks of

data mining projects, leaving the business aspects out (unlike, i.e., CRISP-DM and its Business Understanding phase).

• SEMMA is designed to help the users of the SAS Enterprise Miner software. Therefore, applying it outside Enterprise Miner can be ambiguous.

Page 13: Steps in the Data Mining Process

How Can We Do Data Mining?

Page 14: Steps in the Data Mining Process

How Can We Do Data Mining?

By using the CRISP-DM Methodology

– a standard process

– existing data

– software technologies

– situational expertise

Page 15: Steps in the Data Mining Process

Process Standardization

CRISP-DM: • CRoss Industry Standard Process for Data Mining• Initiative launched Sept.1996• SPSS/ISL, NCR, Daimler-Benz, OHRA• Funding from European commission• Over 200 members of the CRISP-DM SIG worldwide

– DM Vendors - SPSS, NCR, IBM, SAS, SGI, Data Distilleries, Syllogic, Magnify, ..– System Suppliers / consultants - Cap Gemini, ICL Retail, Deloitte & Touche, …– End Users - BT, ABB, Lloyds Bank, AirTouch, Experian, ...

Page 16: Steps in the Data Mining Process

CRISP-DM

•Non-proprietary

•Application/Industry neutral

•Tool neutral

•Focus on business issues

– As well as technical analysis

•Framework for guidance

•Experience base

– Templates for Analysis

– Developed by:– NCR, SPSS, Daimler-Chrysler, OHRA

Page 17: Steps in the Data Mining Process

Why CRISP-DM?

•The data mining process must be reliable and repeatable by

people with little data mining skills

•CRISP-DM provides a uniform framework for

–guidelines

–experience documentation

•CRISP-DM is flexible to account for differences

–Different business/agency problems

–Different data

Page 18: Steps in the Data Mining Process

BusinessUnderstanding

DataUnderstanding

EvaluationData

PreparationModeling

Determine Business Objectives

BackgroundBusiness ObjectivesBusiness Success

Criteria

Situation AssessmentInventory of ResourcesRequirements,Assumptions, andConstraints

Risks and ContingenciesTerminologyCosts and Benefits

Determine Data Mining Goal

Data Mining GoalsData Mining Success

Criteria

Produce Project PlanProject PlanInitial Asessment of Tools and Techniques

Collect Initial DataInitial Data Collection

Report

Describe DataData Description Report

Explore DataData Exploration Report

Verify Data Quality Data Quality Report

Data SetData Set Description

Select Data Rationale for Inclusion /

Exclusion

Clean Data Data Cleaning Report

Construct DataDerived AttributesGenerated Records

Integrate DataMerged Data

Format DataReformatted Data

Select ModelingTechnique

Modeling TechniqueModeling Assumptions

Generate Test DesignTest Design

Build ModelParameter SettingsModelsModel Description

Assess ModelModel AssessmentRevised Parameter Settings

Evaluate ResultsAssessment of Data

Mining Results w.r.t. Business Success Criteria

Approved Models

Review ProcessReview of Process

Determine Next StepsList of Possible ActionsDecision

Plan DeploymentDeployment Plan

Plan Monitoring and Maintenance

Monitoring and Maintenance Plan

Produce Final ReportFinal ReportFinal Presentation

Review ProjectExperience

Documentation

Deployment

Phases and Tasks

Page 19: Steps in the Data Mining Process

Phases in the DM Process: CRISP-DM

Page 20: Steps in the Data Mining Process

Phases in the DM Process (1 & 2)

•Business Understanding:

– Statement of Business Objective

– Statement of Data Mining objective

– Statement of Success Criteria

•Data Understanding

– Explore the data and verify the quality

– Find outliers

Page 21: Steps in the Data Mining Process

Phases in the DM Process (3)

• Data preparation:– Takes usually over 90% of our time

• Collection• Assessment• Consolidation and Cleaning

– table links, aggregation level, missing values, etc

• Data selection– active role in ignoring non-contributory

data?

– outliers?– Use of samples– visualization tools

• Transformations - create new variables

Page 22: Steps in the Data Mining Process

Phases in the DM Process (4)

• Model building

– Selection of the modeling techniques is based upon the data mining objective

– Modeling is an iterative process -different for supervised and unsupervised learning

• May model for either description or prediction

Page 23: Steps in the Data Mining Process

Types of Models

•Prediction Models for Predicting and Classifying

– Regression algorithms (predict numeric outcome): neural networks, rule induction, CART (OLS regression, GLM)

– Classification algorithm predict symbolic outcome): CHAID, C5.0(discriminant analysis, logistic regression)

•Descriptive Models for Grouping and Finding Associations

– Clustering/Grouping algorithms: K-means, Kohonen

– Association algorithms: apriori, GRI

Page 24: Steps in the Data Mining Process

Phases in the DM Process (5)

• Model Evaluation– Evaluation of model: how well it

performed on test data

– Methods and criteria depend on model type:

• e.g., coincidence matrix with classification models, mean error rate with regression models

– Interpretation of model: important or not, easy or hard depends on algorithm

Page 25: Steps in the Data Mining Process

Phases in the DM Process (6)

•Deployment– Determine how the results need to be utilized– Who needs to use them?– How often do they need to be used

•Deploy Data Mining results by:– Scoring a database– Utilizing results as business rules– interactive scoring on-line

Page 26: Steps in the Data Mining Process

Comparison between Methods

Page 27: Steps in the Data Mining Process

Final Comments

• Data Mining can be utilized in any organization that needs to find patterns or relationships in their data.

• By using the CRISP-DM methodology, analysts can have a reasonable level of assurance that their Data Mining efforts will render useful, repeatable, and valid results.

• In 2015, IBM Corporation released a new methodology called Analytics Solutions Unified Method for Data Mining/Predictive Analytics (also known as ASUM-DM) which refines and extends CRISP-DM.

Page 28: Steps in the Data Mining Process

Exercise• An insurance company has in its database, information on commercial insurance contract by

each of its clients . – The most important types of insurance are "Home" , "Auto" , "Life" , "Health" and "Leisure" .

– The insurer also has information on the type of area where the insured (rural , urban ) , occupation and age (numeric) resides.

– The Company now plans to sell a new insurance " Leisure " area , who are already your customer and not have this type of insurance . It intends to organize a promotional event you will be invited only the most promising customers .

– The Marketing of the insurer decided to use the data mining for it. For it has 6 person-months ( PM ) for a period of 20 months. The IT department has experience in using the software SPSS Clementine and Oracle DB . It is this database that are the sales figures of the insurance company .

– The management of the company wants results in the next 18 months and find positive it has sold 500 new policies in the universe of their customers who are currently 12000 people.

• In terms of methodology CRISP- DM :– review the tasks of the first two phases ( business understanding and data understanding ) and define what you

can on these two phases .

– do something similar for the last phase ( deployment )

Page 29: Steps in the Data Mining Process

Bibliography

• CRISP-DM user guide

– Availble in pdf at www.crisp-dm.org

– Glossário

• Articles– Shearer C. The CRISP-DM model: the new blueprint for data mining. Journal

Data Warehousing

• Books– “Data Mining Tecnhiques”, Berry e Linoff, Wiley, 97

• Other– Wikipedia:

http://pt.wikipedia.org/wiki/Cross_Industry_Standard_Process_for_Data_Mining