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Bike Buyer DMX Tutorial

In this tutorial, you will learn how create, train, and explore mining models by using the Data Mining Extensions (DMX) query language. You will then use these mining models to create predictions that determine whether a customer will purchase a bicycle.

The mining models will be created from the data contained in the AdventureWorksDW sample database, which stores data for the fictitious company Adventure Works Cycles. Adventure Works Cycles is a large, multinational manufacturing company. The company manufactures and sells metal and composite bicycles to North American, European, and Asian commercial markets. Its base operation is located in Bothell, Washington, with 290 employees, and it has several regional sales teams located throughout their international market base. For more information about the AdventureWorksDW sample database, see AdventureWorks Sample Data Warehouse.

Tutorial Scenario

Adventure Works Cycles has decided to extend their data analysis by creating a custom application that uses data mining functionality. Their goal for the custom application is to be able to:

  • Take as input specific characteristics about a potential customer and predict whether they will buy a bicycle.

  • Take as input a list of potential customers, as well as characteristics about the customers, and predict which ones will buy a bicycle.

In the first case, customer data is provided by a customer registration page, and in the second case, a list of potential customers is provided by the Adventure Works Cycles marketing department.

In addition, the marketing department has asked for the ability to group existing customers into categories based on characteristics such as where they live, the number of children they have, and their commute distance. They want to see whether these clusters can be used to help target specific kinds of customers. This will require an additional mining model.

Microsoft SQL Server Analysis Services provides several tools that can be used to accomplish these tasks:

Data Mining Extensions (DMX) is a query language provided by Analysis Services that you can use to create and work with mining models. The Microsoft Decision Trees algorithm creates models that can be used to predict whether someone will purchase a bicycle. The resulting model can take an individual customer or a table of customers as an input. The Microsoft Clustering algorithm can create groupings of customers based on shared characteristics. The goal of this tutorial is to provide the DMX scripts that will be used in the custom application.

For more information:Data Mining Projects (Analysis Services - Data Mining)

Mining Structure and Mining Models

Before you begin to create DMX statements, it is important to understand the main objects that Analysis Services uses to create mining models. The mining structure is a data structure that defines the data domain from which mining models are built. A single mining structure can contain multiple mining models that share the same domain. A mining model applies a mining model algorithm to the data, which is represented by a mining structure.

The building blocks of the mining structure are the mining structure columns, which describe the data that the data source contains. These columns contain information such as data type, content type, and how the data is distributed.

Mining models must contain the key column described in the mining structure, as well as a subset of the remaining columns. The mining model defines the usage for each column and defines the algorithm that is used to create the mining model. For example, in DMX you can specify that a column is a Key column or a PREDICT column. If a column is left unspecified, it is assumed to be an input column.

In DMX, there are two ways to create mining models. You can either create the mining structure and associated mining model together by using the CREATE MINING MODEL statement, or you can first create a mining structure by using the CREATE MINING STRUCTURE statement, and then add a mining model to the structure by using the ALTER STRUCTURE statement. These methods are described in the following table.

  • CREATE MINING MODEL
    Use this statement to create a mining structure and associated mining model together using the same name. The mining model name is appended with "Structure" to differentiate it from the mining structure. This statement is useful if you are creating a mining structure that will contain a single mining model.

    For more information, see CREATE MINING MODEL (DMX).

  • ALTER MINING STRUCTURE
    Use this statement to add a mining model to a mining structure that already exists on the server. This statement is useful if you want to create a mining structure that contains several different mining models. There are several reasons that you would want to add more than one mining model in a single mining structure. For example, you might create several mining models that use different algorithms to see which algorithm works best. You might create several mining models that use the same algorithm, but with a parameter set differently for each mining model to find the best setting for the parameter.

    For more information, see ALTER MINING STRUCTURE (DMX).

Because you will create a mining structure that contains several mining models, you will use the second method in this tutorial.

For More Information

Data Mining Extensions (DMX) Reference, Understanding the Select Statement (DMX), Prediction Queries (DMX)

What You Will Learn

This tutorial is divided into the following lessons:

Requirements

Before doing this tutorial, make sure that the following are installed:

  • Microsoft SQL Server 

  • Microsoft SQL Server 2005 Analysis Services (SSAS) or SQL Server 2008 Analysis Services (SSAS) 

  • The AdventureWorks database, which is included with SQL Server. By default, the sample databases are not installed, to enhance security. To install official sample databases for Microsoft SQL Server, visit the Microsoft SQL Sample Databases page and select the databases that you want to install. For more information about how to install the sample databases, see Initial Installation (Analysis Services).

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