296 search results for "Anova"

R Tutorial Series: Two-Way ANOVA with Unequal Sample Sizes

February 28, 2011
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R Tutorial Series: Two-Way ANOVA with Unequal Sample Sizes

When the sample sizes within the levels of our independent variables are not equal, we have to handle our ANOVA differently than in the typical two-way case. This tutorial will demonstrate how to conduct a two-way ANOVA in R when the sample sizes withi...

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R Tutorial Series: Two-Way ANOVA with Unequal Sample Sizes

February 28, 2011
By
R Tutorial Series: Two-Way ANOVA with Unequal Sample Sizes

When the sample sizes within the levels of our independent variables are not equal, we have to handle our ANOVA differently than in the typical two-way case. This tutorial will demonstrate how to conduct a two-way ANOVA in R when the sample sizes withi...

Read more »

R Tutorial Series: Two-Way Repeated Measures ANOVA

February 21, 2011
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R Tutorial Series: Two-Way Repeated Measures ANOVA

Repeated measures data require a different analysis procedure than our typical two-way ANOVA and subsequently follow a different R process. This tutorial will demonstrate how to conduct two-way repeated measures ANOVA in R using the Anova() function fr...

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R Tutorial Series: Two-Way Repeated Measures ANOVA

February 21, 2011
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R Tutorial Series: Two-Way Repeated Measures ANOVA

Repeated measures data require a different analysis procedure than our typical two-way ANOVA and subsequently follow a different R process. This tutorial will demonstrate how to conduct two-way repeated measures ANOVA in R using the Anova() function fr...

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R Tutorial Series: One-Way Repeated Measures ANOVA

February 14, 2011
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R Tutorial Series: One-Way Repeated Measures ANOVA

Repeated measures data require a different analysis procedure than our typical one-way ANOVA and subsequently follow a different R process. This tutorial will demonstrate how to conduct one-way repeated measures ANOVA in R using the Anova(mod, idata, i...

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R Tutorial Series: One-Way Repeated Measures ANOVA

February 14, 2011
By
R Tutorial Series: One-Way Repeated Measures ANOVA

Repeated measures data require a different analysis procedure than our typical one-way ANOVA and subsequently follow a different R process. This tutorial will demonstrate how to conduct one-way repeated measures ANOVA in R using the Anova(mod, idata, i...

Read more »

R Tutorial Series: Two-Way ANOVA with Interactions and Simple Main Effects

February 7, 2011
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R Tutorial Series: Two-Way ANOVA with Interactions and Simple Main Effects

When an interaction is present in a two-way ANOVA, we typically choose to ignore the main effects and elect to investigate the simple main effects when making pairwise comparisons. This tutorial will demonstrate how to conduct pairwise comparisons when...

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R Tutorial Series: Two-Way ANOVA with Interactions and Simple Main Effects

February 7, 2011
By
R Tutorial Series: Two-Way ANOVA with Interactions and Simple Main Effects

When an interaction is present in a two-way ANOVA, we typically choose to ignore the main effects and elect to investigate the simple main effects when making pairwise comparisons. This tutorial will demonstrate how to conduct pairwise comparisons when...

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Post-hoc Pairwise Comparisons of Two-way ANOVA

February 4, 2011
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Post-hoc Pairwise Comparisons of Two-way ANOVA

I read this post today by John Quick. I was a little taken back when he used a pairwise t-test for post hoc analysis. In a contradiction the t-test did not show differences in the treatment means when the ANOVA model did. This is because the pairwise.t.test does not take into account the two-way anova,

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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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