# Blog Archives

## R Tutorial Series: Regression With Interaction Variables

January 23, 2010
By Interaction variables introduce an additional level of regression analysis by allowing researchers to explore the synergistic effects of combined predictors. This tutorial will explore how interaction models can be created in R.Tutorial Files Before we...

## R Tutorial Series: Hierarchical Linear Regression

January 15, 2010
By Regression models can become increasingly complex as more variables are included in an analysis. Furthermore, they can become exceedingly convoluted when things such as polynomials and interactions are explored. Thankfully, once the potential independe...

## R Tutorial Series: ANOVA Tables

January 8, 2010
By The commonly applied analysis of variance procedure, or ANOVA, is a breeze to conduct in R. This tutorial will explore how R can be used to perform ANOVA to analyze a single regression model and to compare multiple models.Tutorial FilesBefore we begin,...

## R Tutorial Series: Graphic Analysis of Regression Assumptions

December 15, 2009
By An important aspect of regression involves assessing the tenability of the assumptions upon which its analyses are based. This tutorial will explore how R can help one scrutinize the regression assumptions of a model via its residuals plot, normality h...

## R Tutorial Series: Multiple Linear Regression

December 8, 2009
By In R, multiple linear regression is only a small step away from simple linear regression. In fact, the same lm() function can be used for this technique, but with the addition of a one or more predictors. This tutorial will explore how R can be used to...

## R Tutorial Series: Simple Linear Regression

November 26, 2009
By Simple linear regression uses a solitary independent variable to predict the outcome of a dependent variable. By understanding this, the most basic form of regression, numerous complex modeling techniques can be learned. This tutorial will explore how ...

## R Tutorial Series: Scatterplots

November 12, 2009
By A scatterplot is a useful way to visualize the relationship between two variables. Similar to correlations, scatterplots are often used to make initial diagnoses before any statistical analyses are conducted. This tutorial will explore the ways in whic...

## R Tutorial Series: Zero-Order Correlations

November 6, 2009
By One of the most common and basic techniques for analyzing the relationships between variables is zero-order correlation. This tutorial will explore the ways in which R can be used to employ this method.Tutorial FilesBefore we start, you may want to dow...

## R Tutorial Series: Summary and Descriptive Statistics

November 1, 2009
By Summary (or descriptive) statistics are the first figures used to represent nearly every dataset. They also form the foundation for much more complicated computations and analyses. Thus, in spite of being composed of simple methods, they are essential ...

## R Tutorial Series: Introduction to The R Project for Statistical Computing (Part 2)

October 15, 2009
By Welcome to part two of the Introduction to The R Project for Statistical Computing tutorial. If you missed part one, it can be found here. In this segment, we will explore the following topics.Importing DataVariablesWorkspace FilesConsole FilesFinding ...