Linear Regression Tutorial
Linear regression is a technique that statisticians use to describe the relationship between a
dependent variable one or more
independent variables.
About the Tutorial
This tutorial covers linear regression in just a few short lessons, focusing on four broad topics:
 Prerequisites. To understand linear regression, you need to understand measurement scales
and correlation.
 The regression model. At its core, linear regression involves fitting a straight line to
a scatterplot of data.
 Analysis. To use regression appropriately, you need to assess how well the
regression line fits the data.
 Inference. And finally, you need to test the data to assess the strength of relationships
between variables.
The tutorial begins with simple linear regression  regression between one dependent variable and a single
independent variable. And the tutorial concludes with multiple linear regression  regression
between one dependent variable and two or more independent variables.
How to Use This Tutorial
Individual lessons are accessible through the table of contents, which can be
found in the vertical column on the left side of the page. You should work through lessons
in the order in which they appear; because some lessons build on
previous lessons.
Individual lessons are accessible through the table of contents, which can be
accessed by tapping the "Linear Regression: Table of Contents" button at the top of the page. You should work through lessons
in the order in which they appear; because some lessons build on
previous lessons.
Additional Helpful Resources
As you progress through the tutorial, take advantage
of the following helpful resources.

Analytical tools. Stat Trek provides a variety of analytical tools 
online statistical tables and probability calulators  to take the drudgery
out of statistical computations. The tutorial will alert you to these tools,
all of which are free.

Sample problems. Most of the lessons include sample problems. The sample
problems test your knowledge. They also illustrate shortcuts and solutions
to common statistics problems.

Online help. Stat Trek's online
Statistics Dictionary takes the mystery out of statistical jargon. If any term or
concept is unclear, visit the dictionary for additional explanation.
Note: The dictionary can be accessed by clicking the Help tab in the main menu (located at the top of this web page).