SAS Enterprise Miner

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Transcript SAS Enterprise Miner

Premiere Products Team Project
SAS Enterprise Miner (Part I)
BCIS 4660
Spring 2006
BCIS 4660 Project
Overview
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Assignment #7
Assignment #8
Assignment #9
Each team will present their work (10-12
slides, 10 minutes)
• All team members will submit PEER
EVALUATIONS to the instructor at the
conclusion of the project. These will be
part of your grade
BCIS 4660 Project
Team Assignments
• Team assignment will be centered around the
team leaders
• The traits of a good leader (according to Nick Evangelopoulos):
– Knowledge on the class project topic
– Track record on producing results/ meeting deadlines
– Ability to push people when they are lazy, without being
insensitive to special needs/ temporary problems
– Leadership by example: Do what you preach
– Being proactive in resolving communication/
management problems at a very early stage, before
they escalate into conflicts
BCIS 4660 Project
Team Assignments
What to do if you have already teamed up:
• If it’s less than 4 in your team, select a leader and
let us know how many more people you need in
your team
• If it’s already 4 of you in the team, select a team
leader and have him/her come up and let us
know your team is full
Tasks for Team Leaders
• Come on up here and introduce yourself by FIRST
NAME. Bring pen and paper.
• Use ONE SENTENCE to elaborate on your leadership
style
• Use ONE SENTENCE to instill confidence and convince
the team members this project is something you can
handle
• Invite team members to come talk to you and then take
their full names and contact info (phone#, e-mail). Send
everybody a confirmation/”thank you” e-mail ASAP
• E-MAIL the instructor your Team Number and the
names of all team members (including your own)
Data Mining
Some slide material taken from: Groth, Han and Kamber, SAS Institute
The UNT/SAS® joint Data Mining
Certificate: New in 2006
• Just approved!
• Free of charge!
• Requires:
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DSCI 2710
DSCI 3710
BCIS 4660
DSCI 4520
Overview of this Presentation
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Introduction to Data Mining
The SEMMA Methodology
Regression/Logistic Regression
Decision Trees
Neural Networks
SAS EM Demo: The Home Equity Loan Case
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Important DM techniques Not Covered today:
Market Basket Analysis
Memory-Based Reasoning
Web Link Analysis
Introduction to DM
“It is a capital mistake to theorize
before one has data.
Insensibly one begins to twist facts
to suit theories, instead of
theories to suit facts.”
(Sir Arthur Conan Doyle: Sherlock Holmes, "A Scandal in
Bohemia")
What Is Data Mining?
• Data mining (knowledge discovery in
databases):
– A process of identifying hidden patterns
and relationships within data (Groth)
• Data mining:
– Extraction of interesting (non-trivial,
implicit, previously unknown and
potentially useful) information or
patterns from data in large databases
Data
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DM and Business Decision Support
– Database Marketing
• Target marketing
• Customer relationship management
– Credit Risk Management
• Credit scoring
– Fraud Detection
– Healthcare Informatics
• Clinical decision support
Multidisciplinary
Statistics
Pattern
Neurocomputing
Recognition
Machine
Data Mining Learning
Databases
KDD
AI
On the News:
Data-mining software digs for business leads
SAN FRANSCISCO, March 8, 2004. Last year,
Congress shut down Pentagon’s Total Information
Awareness programs. Now entrepreneurs are selling new
data- mining tools that do similar things on a smaller scale.
Spoke and Visible Path sell their software primarily to
corporations. The idea is to provide tools for finding helpful
business partners and making blind introductions -allowing, say, a lawyer for Silly Computers Inc. to
electronically ask a former classmate from Harvard who
once did legal work for Microsoft to help him pitch a
business deal to Bill Gates.
How does it work? Both Spoke and Visible Path send so-called crawlers around a corporation's
internal computer network -- sniffing telltale clues, say, from employee Outlook files about who
they e-mail and how often, who replies to particular messages and who doesn't, which names show up
in electronic calendars and phone logs. Then it cross-references those snippets with information
from other company databases, including sales records from PeopleSoft and Salesforce.com.
Data Mining: A KDD Process
Pattern Evaluation
– Data mining: the core
of knowledge
Data Mining
discovery process.
Task-relevant Data
Data Warehouse
Data Cleaning
Data Integration
Databases
Selection
Data Mining and Business
Intelligence
Increasing potential
to support
business decisions
Making
Decisions
Data Presentation
Visualization Techniques
Data Mining
Information Discovery
End User
(Manager)
Business
Analyst
Data
Analyst
Data Exploration
Statistical Analysis, Querying and Reporting
Data Warehouses / Data Marts
OLAP, MDA
Data Sources
Paper, Files, Information Providers, Database Systems, OLTP
DBA
Architecture of a Typical Data Mining
System
Graphical user interface
Pattern evaluation
Data mining engine
Knowledge-base
Database or data
warehouse server
Data cleaning & data integration
Databases
Filtering
Data
Warehouse
Introducing
SAS Enterprise Miner (EM)
The SEMMA Methodology
– Introduced By SAS Institute
– Implemented in SAS Enterprise Miner (EM)
– Organizes a DM effort into 5 activity groups:
Sample
Explore
Modify
Model
Assess
Sample
Input Data Source
Sampling
Data Partition
Explore
Distribution
Explorer
Association
Multiplot
Variable Selection
Insight
Link Analysis
Modify
Data Set
Attributes
Clustering
Transform
Variables
Filter
Outliers
Self-Organized Maps
Kohonen Networks
Time Series
Replacement
Model
Regression
User Defined
Model
Tree
Ensemble
Neural Network
Memory Based
Reasoning
Princomp/
Dmneural
Two-Stage Model
Assess
Assessment
Reporter
Other Types of Nodes – Scoring
Nodes, Utility Nodes
Group Processing
Data Mining Database
Score
SAS Code
C*Score
Control Point
Subdiagram
DATA MINING AT WORK:
Detecting Credit Card Fraud
– Credit card companies want to find a
way to monitor new transactions and
detect those made on stolen credit
cards. Their goal is to detect the fraud
while it is taking place.
– In a few weeks after each transaction
they will know which of the
transactions were fraudulent and which
were not, and they can then use this
data to validate their fraud detection
and prediction scheme.
DATA MINING AT WORK:
Telstra Mobile Combats Churn with SAS®
As Australia's largest mobile service provider, Telstra Mobile is reliant
on highly effective churn management.
In most industries the cost of retaining a customer, subscriber or client
is substantially less than the initial cost of obtaining that customer.
Protecting this investment is the essence of churn management. It
really boils down to understanding customers -- what they want now
and what they're likely to want in the future, according to SAS.
"With SAS Enterprise Miner we can examine
customer behaviour on historical and
predictive levels, which can then show us
what 'group' of customers are likely to churn
and the causes," says Trish Berendsen,
Telstra Mobile's head of Customer
Relationship Management (CRM).
DATA MINING AT WORK:
Reducing armed robberies in South Africa
SAS helped Absa, a Major South African Bank reduce armed
robberies by 41 percent over two years (2002-2003), netting a 38
percent reduction in cash loss and an 11 percent increase in
customer satisfaction ratings.
Absa, one of South Africa's largest banks, uses SAS' data mining
capabilities to leverage their data for better customer relationships
and more targeted marketing campaigns. With SAS analytics, the
bank can also track which branches are more likely to fall victim to a
robbery and take effective preventive measures.
"Absa used to be one of the banks that was
targeted more than other banks; now we're at the
bottom of the list," says Dave Donkin, Absa group
executive of e-business and information
management.
DATA MINING AT WORK:
Strategic Pricing Solutions at MCI
MCI now has a solution for making strategic pricing decisions, driving
effective network analysis, enhancing segment reporting and creating
data for sales leader compensation.
Before implementing SAS, the process of inventorying MCI's
thousands of network platforms and IT systems – determining what
each one does, who runs them, how they help business and which
products they support – was completely manual. The model created
with SAS has helped MCI to catalog all that information and map the
details to products, customer segments and business processes.
"That's something everyone is excited about,"
says Leslie Mote, director of MCI corporate
business analysis. "Looking at the cost of a
system and what it relates to helps you see the
revenue you're generating from particular
products or customers. I can see what I'm doing
better."
Our own example:
The Home Equity Loan Case
• HMEQ Overview
• Determine who should be
approved for a home equity loan.
• The target variable is a binary
variable that indicates whether
an applicant eventually defaulted
on the loan.
• The input variables are variables
such as the amount of the loan,
amount due on the existing
mortgage, the value of the
property, and the number of
recent credit inquiries.
HMEQ case overview
– The consumer credit department of a bank wants to automate
the decision-making process for approval of home equity lines
of credit. To do this, they will follow the recommendations of
the Equal Credit Opportunity Act to create an empirically
derived and statistically sound credit scoring model. The
model will be based on data collected from recent applicants
granted credit through the current process of loan
underwriting. The model will be built from predictive modeling
tools, but the created model must be sufficiently interpretable
so as to provide a reason for any adverse actions (rejections).
– The HMEQ data set contains baseline and loan performance
information for 5,960 recent home equity loans. The target
(BAD) is a binary variable that indicates if an applicant
eventually defaulted or was seriously delinquent. This adverse
outcome occurred in 1,189 cases (20%). For each applicant, 12
input variables were recorded.
The HMEQ Loan process
1. An applicant comes forward with a specific
property and a reason for the loan (HomeImprovement, Debt-Consolidation)
2. Background info related to job and credit
history is collected
3. The loan gets approved or rejected
4. Upon approval, the Applicant becomes a
Customer
5. Information related to how the loan is serviced
is maintained, including the Status of the loan
(Current, Delinquent, Defaulted, Paid-Off)
The HMEQ Loan
Transactional Database
• Entity Relationship Diagram (ERD), Logical Design:
Loan
Reason
Approval
Date
APPLICANT
Applies for
HMEQ Loan on…
using…
becomes
PROPERTY
Balance
Status
OFFICER
CUSTOMER
ACCOUNT
MonthlyPayment
has
HISTORY
HMEQ Transactional database:
the relations
• Entity Relationship Diagram (ERD), Physical Design:
Officer
HMEQLoanApplication
OFFICERID
OFFICERNAME
PHONE
FAX
OFFICERID
APPLICANTID
PROPERTYID
LOAN
REASON
DATE
APPROVAL
Applicant
APPLICANTID
NAME
JOB
DEBTINC
YOJ
DEROG
CLNO
DELINQ
CLAGE
NINQ
Property
PROPERTYID
ADDRESS
VALUE
MORTDUE
Customer
Account
CUSTOMERID
APPLICANTID
NAME
ADDRESS
ACCOUNTID
CUSTOMERID
PROPERTYID
ADDRESS
BALANCE
MONTHLYPAYMENT
STATUS
History
HISTORYID
ACCOUNTID
PAYMENT
DATE
The HMEQ Loan
Data Warehouse Design
• We have some slowly changing attributes:
HMEQLoanApplication: Loan, Reason, Date
Applicant: Job and Credit Score related attributes
Property: Value, Mortgage, Balance
• An applicant may reapply for a loan, then
some of these attributes may have
changed.
– Need to introduce “Key” attributes and make
them primary keys
The HMEQ Loan
Data Warehouse Design
STAR 1 – Loan Application facts
• Fact Table: HMEQApplicationFact
• Dimensions: Applicant, Property, Officer, Time
STAR 2 – Loan Payment facts
• Fact Table: HMEQPaymentFact
• Dimensions: Customer, Property, Account, Time
Two Star Schemas for HMEQ Loans
Applicant
APPLICANTKEY
APPLICANTID
NAME
JOB
DEBTINC
YOJ
DEROG
CLNO
DELINQ
CLAGE
NINQ
Officer
OFFICERKEY
OFFICERID
OFFICERNAME
PHONE
FAX
Property
Customer
PROPERTYKEY
PROPERTYID
ADDRESS
VALUE
MORTDUE
CUSTOMERKEY
CUSTOMERID
APPLICANTID
NAME
ADDRESS
HMEQApplicationFact
HMEQPaymentFact
APPLICANTKEY
PROPERTYKEY
OFFICERKEY
TIMEKEY
LOAN
REASON
APPROVAL
CUSTOMERKEY
PROPERTYKEY
ACCOUNTKEY
TIMEKEY
BALANCE
PAYMENT
STATUS
Time
Account
TIMEKEY
DATE
MONTH
YEAR
ACCOUNTKEY
LOAN
MATURITYDATE
MONTHLYPAYMENT
The HMEQ Loan DW:
Questions asked by management
• How many applications were filed each month during the
last year? What percentage of them were approved each
month?
• How has the monthly average loan amount been
fluctuating during the last year? Is there a trend?
• Which customers were delinquent in their loan payment
during the month of September?
• How many loans have defaulted each month during the
last year? Is there an increasing or decreasing trend?
• How many defaulting loans were approved last year by
each loan officer? Who are the officers with the largest
number of defaulting loans?
The HMEQ Loan DW:
Some more involved questions
• Are there any patterns suggesting which applicants are
more likely to default on their loan after it is approved?
• Can we relate loan defaults to applicant job and credit
history? Can we estimate probabilities to default based
on applicant attributes at the time of application? Are
there applicant segments with higher probability?
• Can we look at relevant data and build a predictive
model that will estimate such probability to default on the
HMEQ loan? If we make such a model part of our
business policy, can we decrease the percentage of
loans that eventually default by applying more stringent
loan approval criteria?
Selecting Task-relevant attributes
Applicant
APPLICANTKEY
APPLICANTID
NAME
JOB
DEBTINC
YOJ
DEROG
CLNO
DELINQ
CLAGE
NINQ
Officer
OFFICERKEY
OFFICERID
OFFICERNAME
PHONE
FAX
Property
Customer
PROPERTYKEY
PROPERTYID
ADDRESS
VALUE
MORTDUE
CUSTOMERKEY
CUSTOMERID
APPLICANTID
NAME
ADDRESS
HMEQApplicationFact
HMEQPaymentFact
APPLICANTKEY
PROPERTYKEY
OFFICERKEY
TIMEKEY
LOAN
REASON
APPROVAL
CUSTOMERKEY
PROPERTYKEY
ACCOUNTKEY
TIMEKEY
BALANCE
PAYMENT
STATUS
Time
Account
TIMEKEY
DATE
MONTH
YEAR
ACCOUNTKEY
LOAN
MATURITYDATE
MONTHLYPAYMENT
HMEQ final task-relevant data file
Name
Model Role
Measurement Level
Description
BAD
Target
Binary
1=defaulted on loan, 0=paid back loan
REASON
Input
Binary
HomeImp=home improvement,
DebtCon=debt consolidation
JOB
Input
Nominal
Six occupational categories
LOAN
Input
Interval
Amount of loan request
MORTDUE
Input
Interval
Amount due on existing mortgage
VALUE
Input
Interval
Value of current property
DEBTINC
Input
Interval
Debt-to-income ratio
YOJ
Input
Interval
Years at present job
DEROG
Input
Interval
Number of major derogatory reports
CLNO
Input
Interval
Number of trade lines
DELINQ
Input
Interval
Number of delinquent trade lines
CLAGE
Input
Interval
Age of oldest trade line in months
NINQ
Input
Interval
Number of recent credit inquiries
HMEQ: Modeling Goal
– The credit scoring model should compute the
probability of a given loan applicant to default
on loan repayment. A threshold is to be
selected such that all applicants whose
probability of default is in excess of the
threshold are recommended for rejection.
– Using the HMEQ task-relevant data file, three
competing models will be built: A logistic
Regression model, a Decision Tree, and a
Neural Network
– Model assessment will allow us to select the
best of the three alternative models
Predictive Modeling
Inputs
Cases
.. .. .. .. .. .. .. .. ..
. . . . . . . . .
Target
...
...
...
...
...
...
...
...
...
...
.. ..
. .
Modeling Tools
Logistic Regression
Modeling Techniques:
Separate Sampling
•
Benefits:
• Helps detect rare target levels
• Speeds processing
Risks:
• Biases predictions (correctable)
• Increases prediction variability
Logistic Regression Models
log(odds)
logit(p )
p
log g-1( p ) = w0 + w1x1 +…+ wpxp
1-p
(
)
logit(p)
1.0
p 0.5
0.0
Training Data
0
Changing the Odds
log
p
(1 - p ) =
p
log
= wexp(w
log
+) w
01 + w
01(x
1+1)+…+
1x1 +…+ wppxpp
1 - p´
1-p
odds
ratio
(
Training Data
p´
w0 + w1x1 +…+ wpxp
)
(
)
Modeling Tools
Decision Trees
Divide and Conquer the
HMEQ data
The tree is fitted to the data by
recursive partitioning.
Partitioning refers to
segmenting the data into
subgroups that are as
homogeneous as possible with
respect to the target. In this
case, the binary split (Debt-toIncome Ratio < 45) was
chosen. The 5,000 cases were
split into two groups, one with
a 5% BAD rate and the other
with a 21% BAD rate.
n = 5,000
10% BAD
yes
n = 3,350
5% BAD
Debt-to-Income
Ratio < 45
no
n = 1,650
21% BAD
The method is recursive because each subgroup results from splitting a subgroup
from a previous split. Thus, the 3,350 cases in the left child node and the 1,650
cases in the right child node are split again in similar fashion.
The Cultivation of Trees
– Split Search
• Which splits are to be considered?
– Splitting Criterion
• Which split is best?
– Stopping Rule
• When should the splitting stop?
– Pruning Rule
• Should some branches be lopped off?
Possible Splits to Consider:
an enormous number
500,000
Nominal
Input
400,000
300,000
Ordinal
Input
200,000
100,000
1
2
4
6
8
10 12 14 16 18 20
Input Levels
Splitting Criteria
How is the best split determined? In some situations, the worth
of a split is obvious. If the expected target is the same in the
child nodes as in the parent node, no improvement was made,
and the split is worthless!
In contrast, if a split results in pure child nodes, the split is
undisputedly best. For classification trees, the three most
widely used splitting criteria are based on the Pearson chisquared test, the Gini index, and entropy. All three measure the
difference in class distributions across the child nodes. The
three methods usually give similar results.
Benefits of Trees
– Interpretability
• tree-structured presentation
– Mixed Measurement Scales
• nominal, ordinal, interval
– Robustness (tolerance to
noise)
– Handling of Missing Values
– Regression trees,
Consolidation trees
Modeling Tools
Neural Networks
Neural network models
(multi-layer perceptrons)
Often regarded as a mysterious and powerful predictive
modeling technique.
The most typical form of the model is, in fact, a natural
extension of a regression model:
•
•
A generalized linear model on a set of derived inputs
These derived inputs are themselves a generalized linear model
on the original inputs
The usual link for the derived input’s model is inverse
hyperbolic tangent, a shift and rescaling of the logit
function
Ability to approximate virtually any continuous
association between the inputs and the target
•
You simply need to specify the correct number of derived inputs
Neural Network Model
x2
log
p
( 1 - p ) = ww
00 +
w01H1 + w02H2 +
03H3
tanh-1( H1 ) = w10 + w11x1 + w12x2
tanh-1( H2 ) = w20 + w21x1 + w22x2
tanh-1( H3 ) = w30 + w31x1 + w32x2
tanh(x)
1
0
Training Data
x1
-1
x
Input layer, hidden layer, output
layer
Multi-layer perceptron models were originally inspired by
neurophysiology and the interconnections between
neurons. The basic model form arranges neurons in
layers.
The input layer connects to a layer of neurons called a
hidden layer, which, in turn, connects to a final layer
called the target, or output, layer.
The structure of a multi-layer perceptron lends itself to a
graphical representation called a network diagram.
Neural Network Diagram
x2
log
p
( 1 - p ) = ww
00 +
w01H1 + w02H2 +
03H3
tanh-1( H1 ) = w10 + w11x1 + w12x2
tanh-1( H2 ) = w20 + w21x1 + w22x2
tanh-1( H3 ) = w30 + w31x1 + w32x2
Inputs
x1
Training Data
x1
x2
H1
H2
H3
Hidden layer
Target
p
Objective Function
Predictions are compared to the actual values of the target
via an objective function.
An easy-to-understand example of an objective function is
the mean squared error (MSE) given by:
1
MSE 
N
Where:
2
ˆ
ˆ
(
y

y
(
w
)
)
 l i
training
cases
– N is the number of training cases.
– yi is the target value of the ith case.
– ŷ i is the predicted target value.
– ŵ is the current estimate of the model parameters.
Overgeneralization
A small value for the objective function, when calculated
on training data, need not imply a small value for the
function on validation data.
Typically, improvement on the objective function is
observed on both the training and the validation data
over the first few iterations of the training process.
At convergence, however, the model is likely to be highly
overgeneralized and the values of the objective
function computed on training and validation data may
be quite different.
Training Overgeneralization
x2
log
p
( 1 - p ) = ww
00 +
w01H1 + w02H2 +
03H3
tanh-1( H1 ) = w10 + w11x1 + w12x2
tanh-1( H2 ) = w20 + w21x1 + w22x2
tanh-1( H3 ) = w30 + w31x1 + w32x2
Objective function (w)
Training Data
x1
0
10
20
30
40
50
60
70
Final Model
To compensate for overgeneralization, the overall average
profit, computed on validation data, is examined.
The final parameter estimates for the model are taken
from the training iteration with the maximum validation
profit.
Neural Network Final Model
x2
log
p
( 1 - p ) = ww
00 +
w01H1 + w02H2 +
03H3
tanh-1( H1 ) = w10 + w11x1 + w12x2
tanh-1( H2 ) = w20 + w21x1 + w22x2
tanh-1( H3 ) = w30 + w31x1 + w32x2
Profit
Training Data
x1
0
10
20
30
40
50
60
70
Next Lecture:
SAS EM Demo: HMEQ Case