Book Image

Data Science with SQL Server Quick Start Guide

By : Dejan Sarka
Book Image

Data Science with SQL Server Quick Start Guide

By: Dejan Sarka

Overview of this book

SQL Server only started to fully support data science with its two most recent editions. If you are a professional from both worlds, SQL Server and data science, and interested in using SQL Server and Machine Learning (ML) Services for your projects, then this is the ideal book for you. This book is the ideal introduction to data science with Microsoft SQL Server and In-Database ML Services. It covers all stages of a data science project, from businessand data understanding,through data overview, data preparation, modeling and using algorithms, model evaluation, and deployment. You will learn to use the engines and languages that come with SQL Server, including ML Services with R and Python languages and Transact-SQL. You will also learn how to choose which algorithm to use for which task, and learn the working of each algorithm.
Table of Contents (15 chapters)
Title Page
Copyright and Credits
Packt Upsell
Contributors
Preface
Index

Chapter 7. Unsupervised Machine Learning

Finally, we are there—we are going to do some real data science now. In the last two chapters, I am going to introduce some of the most popular advanced data mining and machine learning algorithms. I will show you how to use them to get in-depth knowledge from your data.

The most common separation of the algorithms is separation into two groups: the unsupervised, or undirected, and the supervised, or directed algorithms. The unsupervised ones have no target variable. You just try to find some interesting patterns, for example, some distinctive groups of cases, in your data. Then you need to analyze the results to make the interpretation possible. Talking about groups of cases, or clusters – you don't know the labels of those clusters in advance. Once you determine them, you need to check the characteristics of input variables in the clusters in order to get an understanding of the meaning of the clusters.

Before starting with the advanced algorithms...