296 search results for "ANOVA"

R Tutorial Series: Two-Way ANOVA with Pairwise Comparisons

January 31, 2011
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R Tutorial Series: Two-Way ANOVA with Pairwise Comparisons

By extending our one-way ANOVA procedure, we can test the pairwise comparisons between the levels of several independent variables. This tutorial will demonstrate how to conduct pairwise comparisons in a two-way ANOVA. Tutorial FilesBefore we begin, yo...

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R Tutorial Series: One-Way ANOVA with Pairwise Comparisons

January 24, 2011
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R Tutorial Series: One-Way ANOVA with Pairwise Comparisons

When we have more than two groups in a one-way ANOVA, we typically want to statistically assess the differences between each group. Whereas a one-way omnibus ANOVA assesses whether a significant difference exists at all amongst the groups, pairwise com...

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R Tutorial Series: One-Way ANOVA with Pairwise Comparisons

January 24, 2011
By
R Tutorial Series: One-Way ANOVA with Pairwise Comparisons

When we have more than two groups in a one-way ANOVA, we typically want to statistically assess the differences between each group. Whereas a one-way omnibus ANOVA assesses whether a significant difference exists at all amongst the groups, pairwise com...

Read more »

R Tutorial Series: Two-Way Omnibus ANOVA

January 17, 2011
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R Tutorial Series: Two-Way Omnibus ANOVA

As with the one-way case, testing the omnibus hypothesis via two-way ANOVA is simple process in R. This tutorial will explore how R can be used to perform a two-way ANOVA to test the difference between two (or more) group means. Tutorial FilesBefore we...

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R Tutorial Series: Two-Way Omnibus ANOVA

January 17, 2011
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R Tutorial Series: Two-Way Omnibus ANOVA

As with the one-way case, testing the omnibus hypothesis via two-way ANOVA is simple process in R. This tutorial will explore how R can be used to perform a two-way ANOVA to test the difference between two (or more) group means. Tutorial FilesBefore we...

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R Tutorial Series: One-Way Omnibus ANOVA

October 11, 2010
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R Tutorial Series: One-Way Omnibus ANOVA

Testing the omnibus hypothesis via one-way ANOVA is simple process in R. This tutorial will explore how R can be used to perform a one-way ANOVA to test the difference between two (or more) group means. Tutorial FilesBefore we begin, you may want to do...

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R Tutorial Series: One-Way Omnibus ANOVA

October 11, 2010
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R Tutorial Series: One-Way Omnibus ANOVA

Testing the omnibus hypothesis via one-way ANOVA is simple process in R. This tutorial will explore how R can be used to perform a one-way ANOVA to test the difference between two (or more) group means. Tutorial FilesBefore we begin, you may want to do...

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Repeated measures ANOVA with R (tutorials)

April 13, 2010
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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 in the R-help mailing list). So for future reference, I am starting this page...

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Two-way Analysis of Variance (ANOVA)

February 15, 2010
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Two-way Analysis of Variance (ANOVA)

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 the two factors. As an example

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One-way ANOVA (cont.)

February 12, 2010
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One-way ANOVA (cont.)

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 the aov function. The code used

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