Book Image

Data Analysis Using SQL and Excel - Second Edition

By : Gordon S. S. Linoff
Book Image

Data Analysis Using SQL and Excel - Second Edition

By: Gordon S. S. Linoff

Overview of this book

Data Analysis Using SQL and Excel, 2nd Edition shows you how to leverage the two most popular tools for data query and analysis—SQL and Excel—to perform sophisticated data analysis without the need for complex and expensive data mining tools. Written by a leading expert on business data mining, this book shows you how to extract useful business information from relational databases. You'll learn the fundamental techniques before moving into the "where" and "why" of each analysis, and then learn how to design and perform these analyses using SQL and Excel. Examples include SQL and Excel code, and the appendix shows how non-standard constructs are implemented in other major databases, including Oracle and IBM DB2/UDB. The companion website includes datasets and Excel spreadsheets, and the book provides hints, warnings, and technical asides to help you every step of the way. Data Analysis Using SQL and Excel, 2nd Edition shows you how to perform a wide range of sophisticated analyses using these simple tools, sparing you the significant expense of proprietary data mining tools like SAS.
Table of Contents (18 chapters)
Free Chapter
1
Foreword
17
EULA

Lessons Learned

This chapter introduces linear regression (best-fit lines) from the perspective of SQL and Excel. Linear regression is an example of a statistical model and is similar to the models discussed in the previous chapter.

There are several ways to approach linear regressions using SQL and Excel. Excel has at least four ways to create such models for a given set of data. Excel charting has a very nice feature where a trend line can be added to a chart. One of the types of trend lines is the best-fit line, which can be included on a chart along with its equation and statistics describing the line. Other types of trend lines—polynomial fits, exponential curves, power curves, logarithmic curves, and moving averages—are also useful for capturing and visualizing patterns in data.

A second way to estimate coefficients for a linear regression is with the array function LINEST() and various other functions that return individual coefficients, such as SLOPE() and INTERCEPT...