Advanced Analytics
Data Mining using SQL Server
Tuesday, April 17, 2012 from 5:30 PM to 7:30 PM (CT)
Thomas Arehart
Microsoft Technology Center
Growing Business Use
Whether delivered as dashboards, scorecards or standalone tools, the number of
users benefiting from access to business intelligence (BI) and analytics tools is taking
off.
Once limited to only a few number crunchers with degrees in advanced
mathematics, BI and analytics tools are rapidly being deployed to all professionals in
many organizations, and to everyone in a substantial number of companies,
according to analysts and recent surveys.
While traditional BI tools were complex and expensive, access to powerful BI and
analytics capabilities is no longer out of reach for the masses. Today, BI capabilities
are increasingly embedded in a wide range of software applications.
Another reason for the broader use of these tools is that the market has evolved
into a broad ecosystem. A wide swath of vendors in a variety of fields essentially
have collaborated to simplify the technology front ends as well as focused the tools
on specific vertical markets such as retailing, telecom and consumer packaged
goods manufacturing. The BA market ranges from platform technologies such as
data warehouse management to end user-facing analytic applications and BI tool.
(1)
Business Need
With BI capabilities now found in a wide range of software applications as well as
lighter weight, standalone packages, new-generation BI is often invisible to its users.
This lets them focus on making better decisions and serving customers more
effectively as opposed to staying up to speed on the latest technology acronyms.
Knowledge workers need analytical tools to explore the gaps in a process when
things break.
Analytical software that analyzes a multitude of databases and transaction histories
can provide guidance and predictions about future customer needs and behavior.
This guidance empowers employees to anticipate customer needs and reduce costs
and improve overall efficiency.
Companies want more automation and consistency around the decisions employees
make on a daily basis. (1)
Table 1. Steps in the Evolution of Data Mining
Evolutionary Step
Business Question
Enabling Technologies
Product Providers
Data
Characteristics
Data Collection
(1960s)
"What was my total
revenue in the last five
years?"
Spreadsheets, desktop
databases
Microsoft Excel
and Access
Retrospective,
static data
delivery
Data Access
(1980s)
"What were unit sales in
New England last March?"
SQL, relational database Microsoft
management systems
SQLServer
(RDBMS)
Retrospective,
dynamic data
delivery at
record level
Data Warehousing &
Decision Support
"What were unit sales in
New England last March?
Drill down to Boston."
On-line analytic
processing (OLAP),
multidimensional
databases, data
warehouses
Microsoft
Reporting SQL
Server Services
(SSRS),
Microsoft SQL
Server Analysis
Services (SSAS)
Retrospective,
dynamic data
delivery at
multiple levels
"What’s likely to happen to
Boston unit sales next
month? Why?"
Advanced algorithms,
multiprocessor
computers, massive
databases
SQL Server
Integration
Services (SSIS),
Excel Add-In
Prospective,
proactive
information
delivery
(1990s)
Data Mining
(Emerging Today)
Examples of tasks
Predicting a discrete attribute
•Flag the customers in a prospective buyers list as good or poor
prospects.
•Calculate the probability that a server will fail within the next 6
months.
•Categorize patient outcomes and explore related factors.
Microsoft algorithms to use (2)
Microsoft Decision Trees Algorithm
Microsoft Naive Bayes Algorithm
Microsoft Clustering Algorithm
Microsoft Neural Network Algorithm
Predicting a continuous attribute
•Forecast next year's sales.
•Predict site visitors given past historical and seasonal trends.
•Generate a risk score given demographics.
Microsoft Decision Trees Algorithm
Microsoft Time Series Algorithm
Microsoft Linear Regression Algorithm
Predicting a sequence
•Perform clickstream analysis of a company's Web site.
•Analyze the factors leading to server failure.
•Capture and analyze sequences of activities during outpatient
visits, to formulate best practices around common activities.
Microsoft Sequence Clustering Algorithm
Finding groups of common items in transactions
•Use market basket analysis to determine product placement.
•Suggest additional products to a customer for purchase.
•Analyze survey data from visitors to an event, to find which
activities or booths were correlated, to plan future activities.
Microsoft Association Algorithm
Microsoft Decision Trees Algorithm
Finding groups of similar items
•Create patient risk profiles groups based on attributes such as
demographics and behaviors.
•Analyze users by browsing and buying patterns.
•Identify servers that have similar usage characteristics.
Microsoft Clustering Algorithm
Microsoft Sequence Clustering Algorithm
Analytic Algorithm Categories
Regression
a powerful and commonly used algorithm that evaluates the relationship of one variable, the
dependent variable, with one or more other variables, called independent variables. By measuring exactly how
large and significant each independent variable has historically been in its relation to the dependent variable,
the future value of the dependent variable can be estimated. Regression models are widely used in applications,
such as seasonal forecasting, quality assurance and credit risk analysis.
Analytic Algorithm Categories
Clustering /
Segmentation
the process of grouping items together to form categories. You might look at a
large collection of shopping baskets and discover that they are clustered corresponding to health food buyers,
convenience food buyers, luxury food buyers, and so on. Once these characteristics have been grouped together,
they can be used to find other customers with similar characteristics. This algorithm is used to create groups for
applications, such as customers for marketing campaigns, rate groups for insurance products, and crime statistics
groups for law enforcement.
Analytic Algorithm Categories
Nearest Neighbor
quite similar to clustering, but it will only look at others records in the dataset that are “nearest” to a chosen
unclassified record based on a “similarity” measure. Records that are “near” to each other tend to have similar
predictive values as well. Thus, if you know the prediction value of one of the records, you can predict its nearest
neighbor. This algorithm works similar to the way that people think – by detecting closely matching examples.
Nearest Neighbor applications are often used in retail and life sciences applications.
Analytic Algorithm Categories
Association Rules
detects related items in a dataset. Association analysis identifies and groups together similar
records that would otherwise go unnoticed by a casual observer. This type of analysis is often used for market
basket analysis to find popular bundles of products that are related by transaction, such as low-end digital
cameras being associated with smaller capacity memory sticks to store the digital images.
Analytic Algorithm Categories
Decision Tree
a tree-shaped graphical predictive algorithm that represents alternative sequential decisions and the possible outcomes for
each decision. This algorithm provides alternative actions that are available to the decision maker, the probabilistic events
that follow from and affect these actions, and the outcomes that are associated with each possible scenario of actions and
consequences. Their applications range from credit card scoring to time series predictions of exchange rates.
Analytic Algorithm Categories
Sequence Association
detects causality and association between time-ordered events, although the associated events may be spread
far apart in time and may seem unrelated. Tracking specific time-ordered records and linking these records to a
specific outcome allows companies to predict a possible outcome based on a few occurring events. A sequence
model can be used to reduce the number of clicks customers have to make when navigating a company’s
website.
Analytic Algorithm Categories
Neural Network
a sophisticated pattern detection algorithm that uses machine learning techniques to generate predictions. This technique
models itself after the process of cognitive learning and the neurological functions of the brain capable of predicting new
observations from other known observations. Neural networks are very powerful, complex, and accurate predictive models
that are used in detecting fraudulent behavior, in predicting the movement of stocks and currencies, and in improving the
response rates of direct marketing campaigns.
Conventional
BI Reporting
Architecture
Excel Data Analysis Tool Analysis Category
Anova: Single Factor
multiple linear regression
Anova: Two-Factor with replication
multiple linear regression
Anova: Two-Factor without replication
multiple linear regression
Correlation
linear regression
Covariance
linear regression
Descriptive Statistics
linear regression
Exponential Smoothing
naïve forecast
F-Test Two-sample for Variances
linear regression
Fourier Analysis
linear regression
Histogram
linear regression
Moving Average
linear regression
Random Number Generation
N/A
Rank and Percentile
clustering
Regression
linear regression
Sampling
N/A
t-Test: Paired Two Sample for Means
t-Test: Two-Sample Assuming Equal
Variances
t-Test: Two-Sample Assuming Unequal
Variances
linear regression
z-Test: Two Sample for Means
linear regression
linear regression
linear regression
Table Analysis Tools for Excel (SQL Server 2008 Data Mining Add-ins) >
Microsoft SQL Server 2008 Data Mining Add-Ins for Office 2007
Analyze Key Influencers (Table Analysis Tools for Excel)
The Analyze Key Influencers tool enables you to select a column that contains a
desired outcome or target value, and then analyze the patterns in your data to
determine which factors had the strongest influence on the outcome. For
example, if you have a customer list that includes a column that shows the total
purchases for each customer over the past year, you could analyze the table to
determine the customer demographics for your top purchasers.
Microsoft Office 2007 Data Mining Tasks
(4)
Task
Market Basket Analysis
Churn Analysis
Description
Discover items sold together to create recommendations on-the-fly and
to determine how product placement can directly contribute to your
bottom line.
Anticipate customers who may be considering canceling their service
and identify the benefits that will keep them from leaving.
Algorithms
Association
Decision Trees
Decision Trees
Linear Regression
Logistic Regression
Market Analysis
Forecasting
Data Exploration
Unsupervised Learning
Web Site Analysis
Campaign Analysis
Define market segments by automatically grouping similar customers
together. Use these segments to seek profitable customers.
Clustering
Predict sales and inventory amounts and learn how they are
interrelated to foresee bottlenecks and improve performance.
Decision Trees
Analyze profitability across customers, or compare customers that
prefer different brands of the same product to discover new
opportunities.
Identify previously unknown relationships between various elements of
your business to inform your decisions.
Understand how people use your Web site and group similar usage
patterns to offer a better experience.
Spend marketing funds more effectively by targeting the customers
most likely to respond to a promotion.
Neural Network
Sequence Clustering
Time Series
Neural Network
Sequence Clustering
Decision Trees
Naïve Bayes
Clustering
Information Quality
Text Analysis
Identify and handle anomalies during data entry or data loading to
improve the quality of information.
Analyze feedback to find common themes and trends that concern your
customers or employees, informing decisions with unstructured input.
Linear Regression
Logistic Regression
Text Mining
Data Analysis Expressions (DAX) is the standard PowerPivot formula language that supports
custom calculations in PowerPivot tables and Excel PivotTables. While many of the
functions used in Excel are included, DAX also offers additional functions for carrying out
dynamic aggregation and other operations with your data. (8)
(7)
Time related calculated measures (10)
Dax Formula
=IF( COUNTROWS(VALUES(DimDate[CalendarYear]))=1
, CALCULATE([Sales], PREVIOUSYEAR(DimDate[DateKey]))
, BLANK()
) OR
or
=IF(
COUNTROWS(VALUES(DimDate[CalendarYear]))=1 ,
CALCULATE([Sales], PARALLELPERIOD(DimDate[Datekey],-12,MONTH))
, BLANK()
)
Description
Previous Year
or
=IF(
COUNTROWS(VALUES(DimDate[CalendarYear]))=1 ,
[Sales] (PARALLELPERIOD(DimDate[Datekey],-12,MONTH)),
BLANK()
)
=IF(COUNTROWS(VALUES(DimDate[CalendarYear]) = 1
, [Sales] - CALCULATE([Sales], PREVIOUSYEAR(DimDate[Datekey]))
, Blank()
)
Sales] - CALCULATE([Sales], PREVIOUSYEAR(DimDate[Datekey]))
, Blank()
)
Year over year growth
Reporting is a fundamental activity in most businesses, and SQL Server 2008 Reporting
Services provides a comprehensive solution for creating, rendering, and deploying reports
throughout the enterprise. SQL Server Reporting Services can render reports directly from a
data mining model by using a data mining extensions (DMX) query. This enables users to
visualize the content of data mining models for optimized data representation.
Furthermore, the ability to query directly against the data mining structure enables users to
easily include attributes beyond the scope of the mining model requirements, presenting
complete and meaningful information. (4)
The DMX query editor for SQL Server Reporting Services
For more information about the functions that are supported for each model type,
see the following links:
Association Model Query Examples
Microsoft Naive Bayes Algorithm
Clustering Model Query Examples
Neural Network Model Query Examples
Decision Trees Model Query Examples
Sequence Clustering Model Query Examples
Linear Regression Model Query Examples
Time Series Model Query Examples
Logistic Regression Model Query Examples
You can also call VBA functions, or create your own functions. For more information,
see Functions (DMX).
Prediction Queries (Data Mining) (9)
SELECT
PredictTimeSeries([Forecasting].[Amount]) as [PredictedAmount]
, PredictTimeSeries([Forecasting].[Quantity]) as [PredictedQty]
FROM
[Forecasting]
SQL Server 2008 data mining supports a number of application programming interfaces
(APIs) that developers can use to build custom solutions that take advantage of the
predictive analysis capabilities in SQL Server. DMX, XMLA, OLEDB and ADOMD.NET, and
Analysis Management Objects (AMO) offer a rich, fully documented development platform,
empowering developers to build data mining aware applications and providing real-time
discovery and recommendation through familiar tools.
This extensibility creates an opportunity for business organizations and independent
software vendors (ISVs) to embed predictive analysis into line-of-business applications,
introducing insight and forecasting that inform business decisions and processes. For
example, the Analytics Foundation adds predictive scoring to Microsoft Dynamics® CRM, to
enable information workers across sales, marketing, and service organizations to identify
attainable opportunities that are more likely to lead to a sale, increasing efficiency and
improving productivity (for more information, see the Microsoft Dynamics site).
Integration Services Data Mining Tasks and Transformations
-------------------------------------------------------------------------------SQL Server Integration Services provides many components that support data mining.
Some tools in Integration Services are designed to help automate common data mining tasks,
including prediction, model building, and processing.
For example:
1)Create an Integration Services package that automatically updates the model every time the
dataset is updated with new customers
2)Perform custom segmentation or custom sampling of case records.
3)Automatically generate models passed on parameters.
However, you can also use data mining in a package workflow, as an input to other processes.
For example:
1) Use probability values generated by the model to weight scores for text mining or other
classification tasks.
2) Automatically generate predictions based on prior data and use those values to assess the
validity of new data.
3) Using logistic regression to segment incoming customers by risk.
Microsoft SQL Server 2008 Integration Services provides a powerful, extensible ETL platform
that Business Intelligence solution developers can use to implement ETL operations . SQL Server
Integration Services includes a Data Mining Model Training destination for training data mining
models, and a Data Mining Query transformation that can be used to perform predictive
analysis on data as it is passed through the data flow. Integrating predictive analysis with
SQL Server Integration Services enables organizations to flag unusual data, classify business
entities, perform text mining, and fill-in missing values on the fly based on the power and insight
of the data mining algorithms. (4)
Data mining in SQL Server Integration Services
After you have created a mining structure and mining model by using the Data Mining Wizard,
you can use the Data Mining Designer from either SQL Server Data Tools (SSDT) or SQL Server
Management Studio to work with existing models and structures.
The designer includes tools for these tasks:
1) Modify the properties of mining structures, add columns and create column aliases,
change the binning method or expected distribution of values.
2) Add new models to an existing structure; copy models, change model properties or
metadata, or define filters on a mining model.
3) Browse the patterns and rules within the model; explore associations or decision
trees. Get detailed statistics about
4) Custom viewers are provided for each different time of model, to help you analyze
your data and explore the patterns revealed by data mining.
5) Validate models by creating lift charts, or analyzing the profit curve for models.
Compare models using classification matrices, or validate a data set and its models
by using cross-validation.
6) Create predictions and content queries against existing mining models. Build one-off
queries, or set up queries to generate predictions for entire tables of external data.
SQL Server 2008 Analysis Services provides a highly scalable platform for multidimensional
OLAP analysis. Many customers are already reaping the benefits of creating a unified
dimensional model (UDM) in Analysis Services and using it to slice and dice business
measures by multiple dimensions. Predictive analysis, being part of SQL Server 2008 Analysis
Services provides a richer OLAP experience, featuring data mining dimensions that slice your
data by the hidden patterns within.(4)
A data mining dimension in an OLAP cube
Data Mining Algorithms
(Analysis Services - Data Mining)
Choosing an Algorithm
by Task
To help you select an
algorithm for use with a
specific task, the
following table provides
suggestions for the
types of tasks for which
each algorithm is
traditionally used.
Examples of tasks
Predicting a discrete attribute
Flag the customers in a prospective buyers list as good
or poor prospects.
Calculate the probability that a server will fail within
the next 6 months.
Categorize patient outcomes and explore related
factors.
Predicting a continuous attribute
Forecast next year's sales.
Predict site visitors given past historical and seasonal
trends.
Generate a risk score given demographics.
Predicting a sequence
Perform clickstream analysis of a company's Web site.
Analyze the factors leading to server failure.
Capture and analyze sequences of activities during
outpatient visits, to formulate best practices around
common activities.
Finding groups of common items in transactions
Use market basket analysis to determine product
placement.
Suggest additional products to a customer for
purchase.
Analyze survey data from visitors to an event, to find
which activities or booths were correlated, to plan
future activities.
Finding groups of similar items
Create patient risk profiles groups based on attributes
such as demographics and behaviors.
Analyze users by browsing and buying patterns.
Identify servers that have similar usage
characteristics.
Microsoft algorithms to use
Microsoft Decision Trees Algorithm
Microsoft Naive Bayes Algorithm
Microsoft Clustering Algorithm
Microsoft Neural Network Algorithm
Microsoft Decision Trees Algorithm
Microsoft Time Series Algorithm
Microsoft Linear Regression Algorithm
Microsoft Sequence Clustering Algorithm
Microsoft Association Algorithm
Microsoft Decision Trees Algorithm
Microsoft Clustering Algorithm
Microsoft Sequence Clustering Algorithm
Many businesses use KPIs to evaluate critical business metrics against targets. SQL Server 2008
Analysis Services provides a centralized platform for KPIs across the organization, and
integration with Microsoft Office PerformancePoint® Server 2007 enables decision makers to
build business dashboards from which they can monitor the company’s performance. KPIs are
traditionally retrospective, for example showing last month’s sales total compared to the sales
target. However, with the insights made possible through data mining, organizations can build
predictive KPIs that forecast future performance against targets, giving the business an
opportunity to detect and resolve potential problems proactively. Predictive analysis can detect
attributes that influence KPIs. Together with Office PerformancePoint Server 2007, users can
monitor trends in key influencers to recognize those attributes that have a sustained effect.
Such insights enable businesses to inform and improve their response strategy. (4)
Microsoft Office PerformancePoint Server 2007
The SQL Server data mining toolset is fully extensible through Microsoft .NET–stored
procedures, plug-in algorithms, custom visualizations and PMML. This enables developers
to extend the out-of-the-box data mining technologies of SQL Server 2008 to meet
uncommon business needs that are specific to the organization by:
 Creating custom data mining algorithms to solve business-specific analytical problems.
 Using data mining algorithms from other software vendors.
 Creating custom visualizations of data mining models through plug-in viewer APIs.
Although the data mining functionality provided with SQL Server 2008 is comprehensive
enough to meet the needs of a wide range of business scenarios, its extensibility ensures
that it can be used to solve virtually any predictive problem. The ability to extend the
data mining technologies of SQL Server through custom algorithms and visualizations,
together with the ability to embed predictive functionality into line-of-business
applications makes SQL Server 2008 a powerful platform for introducing predictive
analysis into existing business processes to add insight and recommendations into
everyday operations. (4)
Plugin Algorithms
SQL Server 2012
SQL Server 2008 R2
SQL Server 2008
SQL Server 2005
In addition to the algorithms that Microsoft SQL Server Analysis Services provides, there
are many other algorithms that you can use for data mining. Accordingly, Analysis
Services provides a mechanism for "plugging in" algorithms that are created by third
parties. As long as the algorithms follow certain standards, you can use them within
Analysis Services just as you use the Microsoft algorithms. Plugin algorithms have all the
capabilities of algorithms that SQL Server Analysis Services provides.
For a full description of the interfaces that Analysis Services uses to communicate with
plugin algorithms, see the samples for creating a custom algorithm and custom model
viewer that are published on CodePlex Web site.
One Way ANOVA (Analysis of Variance)
When to Use One-Way, Single Factor ANOVA
In a manufacturing or service environment, you might wonder if changing a
formula, process or material might deliver a better product at a lower cost. Saving
a penny a pound on five million pounds a month can really add up. Saving ten
minutes of wait time in hospital might add $100,000 to the bottom line and
deliver better patient outcomes. Comparing two or more drug formulations might
pinpoint the best drug for a desired result.
How can you compare the old formula with a new one and be certain that you
have an opportunity to improve? Use one-way ANOVA (also known as single factor
ANOVA) to determine if there's a statistically significant difference between two or
more alternatives.
One Way ANOVA (Analysis of Variance)
Imagine that you manufacture paper bags and that you want to improve the tensile
strength of the bag. You suspect that changing the concentration of hardwood in the bag
will change the tensile strength. You measure the tensile strength in pounds per square
inch (PSI).
So, you decide to test this at 5%, 10%, 15% and 20% hardwood concentration levels.
These "levels" are also called "treatments."
Since we are only evaluating a single factor (hardwood concentration) this is called
one-way ANOVA.
The null hypothesis is that the means are equal:
H0: Mean1 = Mean2 = Mean3 = Mean4
The alternate hypothesis is that at least one of the means are different:
Ha: At least one of the means is different
To conduct the one-way ANOVA test, you need to randomize the trials (assumption #1).
Imagine that we've conducted these trials at each of the four levels of hardwood
concentration.
One Way ANOVA (Analysis of Variance)
You'll find the results of these trials in the ANOVA test data provided with the QI Macros
at c:\qimacros\testdata\anova.xls.
The QI Macros will prompt you for the significance level you desire.
While the default is 0.05 (95% confident), in this example we want to be even more
certain, so we use 0.01 (99% confident).
One Way ANOVA (Analysis of Variance)
Interpreting the Anova One Way test results
The QI Macros automatically compares the p value to a, but you might want to know how to
do this manually. The "null" hypothesis assumes that there is no difference between the
hardwood concentrations.
The P-value of 0.000 is less than the significance level (0.01), so we can reject the null
hypothesis and safely assume that hardwood concentration affects tensile strength.
F (19.60521) is greater than F crit (4.938193), so again, we can reject the null hypothesis.
Interpreting the Anova One Way test results
The QI Macros automatically compares the p value to a, but you might want to know how to do
this manually. The "null" hypothesis assumes that there is no difference between the hardwood
concentrations.
If
test statistic > critical value
(i.e. F> Fcrit)
test statistic < critical value
(i.e. F< Fcrit)
p value < a
p value > a
Then
Reject the null hypothesis
Accept the null hypothesis
Reject the null hypothesis
Accept the null hypothesisThe P-value of 0.000 is
less than the significance level (0.01), so we can
reject the null hypothesis and safely assume that
hardwood concentration affects tensile strength. F
(19.60521) is greater than F crit (4.938193), so
again, we can reject the null hypothesis.
One Way ANOVA (Analysis of Variance)
Now we can look at the average tensile strength and variances:
The average tensile strength increases, but we cannot say for certain which means differ. The variance at the 15% level looks substantially lower
than the other levels. We might need to do additional analysis.
If we reran the one way Anova test with just 10% and 15%, we'd discover there is no statistically significant difference between the two means.
The P value (0.349) is greater than the signficance level (0.01), so we cannot reject the null hypothesis that the means are equivalent.
And F (0.963855) is less than F crit (10.04429) so we cannot reject the null hypothesis.
Based on this analysis, if we were aiming for a tensile strength of 15 PSI or greater, the 10% level might be more cost effective.
Two Way ANOVA (Analysis of Variance) Without Replication
What's cool about QI Macros Two-Way ANOVA?
Unlike other statistical software, the QI Macros is the only SPC software that compares the
p-values to the significance level and tells you when to "Accept or Reject the Null
Hypothesis" and what that tells you: "Means are Same or Different ".
Two Way Anova (Analysis of variance) , also known as two factor Anova, can help you
determine if two factors have the same "mean" or average. This is a form of "hypothesis
testing."
Two Way ANOVA (Analysis of Variance) Without Replication
The null hypothesis is that the means are equal:
•H0: Factor 1's Means = Factor 2's Means
The alternate hypothesis is:
•Ha: The means are different.
The goal is to accept or reject the null hypothesis (i.e., the samples have different means)
at a certain confidence level (95% or 99%).
Two Way ANOVA (Analysis of Variance) Without Replication
Using Excel and the QI Macros, run a two-way analysis without replication
(alpha=0.05 for a 95% confidence).
Click on QI Macros menu and select: ANOVA Two Factor without replication.
Two Way ANOVA (Analysis of Variance) Without Replication
Interpreting the Anova Two Way Without Replication Results
In case you want to know how to do this manually, use these instructions.
Here, the P-value for Rows (i.e., golfers) is less than alpha (0.05), so we can reject the hypothesis that all of the golfers are the same. The P-Value for
Columns (i.e., golf balls) is also less than alpha, so we can reject the hypothesis that all of the golf balls are the same.
Interpreting the Anova Two Way Without Replication Results
In case you want to know how to do this manually, use these instructions.
If
test statistic > critical value
(i.e. F> Fcrit)
test statistic < critical value
(i.e. F< Fcrit)
p value < a
p value > a
Then
Reject the null hypothesis
Accept the null hypothesis
Reject the null hypothesis
Accept the null hypothesisHere, the P-value for Rows
(i.e., golfers) is less than alpha (0.05), so we can
reject the hypothesis that all of the golfers are the
same. The P-Value for Columns (i.e., golf balls) is also
less than alpha, so we can reject the hypothesis that
all of the golf balls are the same.
Two Way ANOVA (Analysis of Variance) Without Replication
It does look like Brand B and C are similar. We could run a paired two sample t test on Brands B
and C to determine if they deliver the same average distance.
Since the p values are greater than alpha (0.05), we can accept the null hypothesis that there is
no difference between the two brands of golf balls, except perhaps price.
Since the p values are greater than alpha (0.05), we can accept the null hypothesis that
there is no difference between the two brands of golf balls, except perhaps price.
Two Way ANOVA (Analysis of Variance)
With Replication
When to Use Two Way Anova
Two Way Anova (Analysis of variance) , also known as two factor Anova, can help
you determine if two or more samples have the same "mean" or average. This is a
form of "hypothesis testing."
The null hypothesis is that the means are equal. The alternate hypothesis is that
the means are not equal.
•H0: Mean1 = Mean2 = Mean3
•Ha: Mean1 <> Mean2 <> Mean3
The goal is to accept or reject the null hypothesis (i.e., the samples have different
means) at a certain confidence level (95% or 99%).
Two Way ANOVA (Analysis of Variance)
With Replication
What if you have two populations of patients (male/female) and three different kinds of
medications, and you want to evaluate their effectiveness? You might run a study with
three "replications", three men and three women.
Two Way ANOVA (Analysis of Variance)
With Replication
What's cool about QI Macros ANOVA?
Unlike other statistical software, the QI Macros is the only SPC software
that compares the p-values (0.179) to the signficance (0.05) and tells
you to "Accept the Null Hypothesis because p>0.05" and that the
"Means are the same ".
Using the QI Macros, run a two-way Anova analysis with replication (alpha=0.05 for a
95% confidence).
Two Way ANOVA (Analysis of Variance)
With Replication
Interpreting the Anova Two Way Results
In case you want to know how to do this manually, use these
instructions:
If
test statistic > critical value
(i.e. F> Fcrit)
test statistic < critical value
(i.e. F< Fcrit)
p value < a
p value > a
Then
Reject the null hypothesis
Accept the null hypothesis
Reject the null hypothesis
Accept the null hypothesisHere, the P-value for
Male/Female is greater than alpha (.179> .05),
so we accept the null hypothesis that the
means are the same. The P-Value for Drugs is
greater than alpha (.106 > .05), so the null
hypothesis holds as well (means are the same).
The P-value for the interaction of the drugs and
patients is less than alpha (.006< .05), so we
reject the null hypotheis and can say that the
effectiveness of the drugs is not the same for
the two categories of patients.
References
1) Pervasive insights produce better business decision opening access to business intelligence by
embedding analytics capabilities into everyday software tools pays substantial dividends.
By Lauren Gibbons Paul
2) Data Mining Algorithms (Analysis Services - Data Mining)
http://msdn.microsoft.com/en-us/library/ms175595.aspx
3) Data Mining Query Task
http://msdn.microsoft.com/en-us/library/ms141728.aspx
4) Predictive Analysis with SQL Server 2008 - White Paper - Microsoft - Published: November 2007
5) Predictive Analytics for the Retail Industry - White Paper - Microsoft - Writer: Matt Adams
Technical Reviewer: Roni Karassik, Published: May 2008
6) Breakthrough Insights using Microsoft SQL Server 2012 - Analysis Services
https://www.microsoftvirtualacademy.com/tracks/breakthrough-insights-using-microsoft-sql-server2012-analysis-services
7) Useful DAX Starter Functions and Expressions
http://thomasivarssonmalmo.wordpress.com/category/powerpivot-and-dax/
8) Stairway to PowerPivot and DAX - Level 1: Getting Started with PowerPivot and DAX
By Bill_Pearson, 2011/12/21
9) Data Mining Tool
http://technet.microsoft.com/en-us/library/ms174467.aspx
10) DAX Cheat Sheet
http://powerpivot-info.com/post/439-dax-cheat-sheet