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Introduction to Data Mining

Jiang Li

Department of Computer Science & Information Technology

Austin Peay State University

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Outline

Data Collected

Knowledge Discovery – An Iterative Process

Data Mining Examples

Data Mining Functions and Algorithms

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Data Collected

Business Wal-Mart

20 million transactions a day Mobile Oil Corporation

A 100 terabytes data warehouse Science

The human genome database project

Gigabytes of data NASA Earth Observing System (EOS)

50 gigabytes data per hour Radio, Television, and Film Studios

Multimedia databases WWW – the infinite resources

Email – huge digital libraries

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Data vs. Knowledge

Technology is available to help us collect data Bar code, cameras, scanners, Radars, satellites, etc.

Technology is available to help us store data Databases, data warehouses, variety of repositories

We are swamped by data that pours on us We need to interpret this data in search for new knowledge

Our need is to extract interesting knowledge (rules, regularities, patterns, constraints) from data in large collections.

“We are drowning in information, but starving for knowledge.” John Naisbitt

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Evolution of Database Technology

1960s: Data collection, database creation (hierarchical

and network models) 1970s:

Relational data model, relational DBMS implementation

1980s: Ubiquitous RDBMS, advanced data models

(extended-relational, Object-Oriented, deductive, etc.) and application-oriented DBMS (spatial, scientific, engineering, etc.)

1990s: Data mining and data warehousing, multimedia

databases, and Web-based database technology

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Knowledge Discovery

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Data Mining

In theory, data mining is a step in the knowledge discovery process. It is the extraction of implicit information from a large dataset.

In practice, data mining and knowledge discovery are becoming synonyms.

KDD – Knowledge Discovery and Data Mining

Notice the misnomer for data mining. Shouldn’t it be knowledge mining?

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Steps of a KDD Process

Learning the application domain relevant prior knowledge and goals of

application Gathering and integrating of data Cleaning and preprocessing data (may

take 60% of effort!) Reducing and projecting data

Find useful features, dimensionality/variable reduction,…

Choosing mining functions and algorithms

summarization, classification, regression, association,…

Data mining: search for patterns of interest

Evaluating results Interpretation: analysis of results

visualization, alteration, removing redundant patterns,…

Use of discovered knowledge

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Data Mining – On What Kind of Data?

Flat Files Generic Data

Relational & Object-Relational Databases Object-Oriented Databases

Multimedia Data Text Databases Audio, Image, and Video Databases

Business Data Transactional Databases

Engineering Data Spatial databases Temporal and Time-series databases

WWW Data

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Data Mining Examples

Data mining is primarily used today by companies with a strong consumer focus - retail, financial, communication, and marketing organizations.

It enables these companies to determine relationships among "internal" factors such as price, product positioning, or staff skills, and "external" factors such as economic indicators, competition, and customer demographics.

And, it enables them to determine the impact on sales, customer satisfaction, and corporate profits.

Finally, it enables them to "drill down" into summary information to view detail transactional data.

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Data Mining Examples

With data mining, a retailer could use point-of-sale records of customer purchases to send targeted promotions based on an individual's purchase history.

By mining demographic data from comment or warranty cards, the retailer could develop products and promotions to appeal to specific customer segments.

Blockbuster Entertainment mines its video rental history database to recommend rentals to individual customers.

American Express can suggest products to its cardholders based on analysis of their monthly expenditures.

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Data Mining Examples

WalMart is pioneering massive data mining to transform its supplier relationships.

WalMart captures point-of-sale transactions from over 2,900 stores in 6 countries and continuously transmits this data to its massive 7.5 terabyte Teradata data warehouse.

WalMart allows more than 3,500 suppliers, to access data on their products and perform data analyses.

These suppliers use this data to identify customer buying patterns at the store display level.

They use this information to manage local store inventory and identify new merchandising opportunities.

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Business Data Mining Examples

The NBA is exploring a data mining application that can be used in conjunction with image recordings of basketball games.

The Advanced Scout software analyzes the movements of players to help coaches orchestrate plays and strategies.

For example, an analysis of the play-by-play sheet of the game played between the New York Knicks and the Cleveland Cavaliers on January 6, 1995 reveals that when Mark Price played the Guard position, John Williams attempted four jump shots and made each one!

A coach can automatically bring up the video clips showing each of the jump shots attempted by Williams with Price on the floor, without needing to comb through hours of video footage.

Those clips show a very successful pick-and-roll play in which Price draws the Knick's defense and then finds Williams for an open jump shot.

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Data Mining Functions and Algorithms

Association Rules Data can be mined to identify associations.

The butter->bread example is an example of associative mining. To find rules like “inside(x, city) near(x, highway)”.

Classification and Prediction Classify data based on the values in a classifying attribute,

e.g., classify countries based on climate classify cars based on gas mileage

Stored data is used to locate data in predetermined groups. A restaurant chain could mine customer purchase data to

determine when customers visit and what they typically order. This information could be used to increase traffic by having daily specials.

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Data Mining Functions and Algorithms

Clustering Data items are grouped according to logical relationships or

consumer preferences. Data can be mined to identify market segments or consumer

affinities. To cluster houses to find distribution patterns.

Sequential patterns Data is mined to anticipate behavior patterns and trends.

An outdoor equipment retailer could predict the likelihood of a backpack being purchased based on a consumer's purchase of sleeping bags and hiking shoes.

To find and characterize similar sequences and deviation data, e.g., stock analysis.

To find segment-wise or total cycles or periodic behaviors in time-related data.

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Data Mining – Linear Classification

D ebt

Incom e

Loan

N o Loan

$T

A simple linear classification boundary for the loan data set: shaded region denotes class “no loan”

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Data Mining - Confluence of Multiple Disciplines