# ANOVA

### One-Way ANOVA

September 11, 2012 |

One-Way ANOVA Analysis of variance is a tool used for a variety of purposes. Applications range from a common one-way ANOVA, to experimental blocking, to more complex nested designs. This first ANOVA example provides the necessary tools to analyze data using this technique. This example will show a basic one-way ... [Read more...]

### Confirming SSR, SSE, and SST using matrix in R

February 1, 2012 |

The codes below was done in our regression laboratory class. Here, we run first the data in SPSS, and take the ANOVA output where we can find the computed values of SSR, SSE, and SST.ANOVAb Model Sum of Squares df Mean Square F Sig. 1 Regress... ### Legendre & Borcard: Nested ANOVA by Permutation

May 30, 2011 |

..here's a very illustrative R-Script example by Legendre & Borcard showing how a Nested ANOVA can be done by permutation.Read more » ### One-way ANOVAs in R – including post-hocs/t-tests and graphs

May 11, 2011 |

In this post, I go over the basics of running an ANOVA using R. The dataset I’ll be examining comes from this website, and I’ve discussed it previously (starting here and then here). I’ve not seen many examples where someone runs through the … Continue reading → [Read more...]

### Book Review: Mixed Effects Models and Extensions in Ecology with R

January 14, 2011 |

A brief review of Zuur et al.'s book "Mixed Effects Models and Extensions in Ecology with R". [Read more...]

### New edition of “R Companion to Applied Regression” – by John Fox and Sandy Weisberg

December 10, 2010 |

Just two hours ago, Professor John Fox has announced on the R-help mailing list of a new (second) edition to his book “An R and S Plus Companion to Applied Regression”, now title . “An R Companion to Applied Regression, Second Edition”. John Fox is (very) well known in the R ... [Read more...]

### R Commander – two-way analysis of variance

June 25, 2010 |

Two way analysis of variance models can be fitted to data using the R Commander GUI. The general approach is similar to fitting the other types of model in R Commander described in previous posts. Fast Tube by Casper The “Statistics” menu provides access to some analysis of variance models ... [Read more...]

### R Commander – one-way analysis of variance

June 25, 2010 |

One way analysis of variance models can be fitted to data using the R Commander GUI. The general approach is similar to fitting the other types of model in R Commander described in previous posts. Fast Tube by Casper The “Statistics” menu provides access to some analysis of variance models ... [Read more...]

### Analysis of Covariance – Extending Simple Linear Regression

April 28, 2010 |

The simple linear regression model considers the relationship between two variables and in many cases more information will be available that can be used to extend the model. For example, there might be a categorical variable (sometimes known as a covariate) that can be used to divide the data set ... ### Repeated measures ANOVA with R (tutorials)

April 13, 2010 |

Repeated measures ANOVA is a common task for the data analyst. There are (at least) two ways of performing “repeated measures ANOVA” using R but none is really trivial, and each way has it’s own complication/pitfalls (explanation/solution to which I was usually able to find through searching ... [Read more...]

### Post hoc analysis for Friedman’s Test (R code)

February 22, 2010 |

My goal in this post is to give an overview of Friedman’s Test and then offer R code to perform post hoc analysis on Friedman’s Test results. (The R function can be downloaded from here) Preface: What is Friedman’s Test Friedman test is a non-parametric randomized block ... ### Two-way Analysis of Variance (ANOVA)

February 15, 2010 |

The analysis of variance (ANOVA) model can be extended from making a comparison between multiple groups to take into account additional factors in an experiment. The simplest extension is from one-way to two-way ANOVA where a second factor is included in the model as well as a potential interaction between ... ### One-way ANOVA (cont.)

February 12, 2010 |

In a previous post we considered using R to fit one-way ANOVA models to data. In this post we consider a few additional ways that we can look at the analysis. In the analysis we made use of the linear model function lm and the analysis could be conducted using ... ### One-way Analysis of Variance (ANOVA)

February 3, 2010 |

Analysis of Variance (ANOVA) is a commonly used statistical technique for investigating data by comparing the means of subsets of the data. The base case is the one-way ANOVA which is an extension of two-sample t test for independent groups covering situations where there are more than two groups being ...  