1415 search results for "regression"

The R-Files: Saptarshi Guha

October 11, 2010
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The R-Files: Saptarshi Guha

"The R-Files" is an occasional series from Revolution Analytics, where we profile prominent members of the R Community. Name: Saptarshi Guha Background: Ph.D. in Statistics, Purdue University Nationality: India Years Using R: 6 Known for: Developing RHIPE package for R + Hadoop integration At just 31 years old, Saptarshi Guha has emerged as a cutting-edge contributor to the R...

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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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Students in predominantly ethnic minority classes want segregated education very much. The others don’t.

October 7, 2010
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Students in predominantly ethnic minority classes want segregated education very much. The others don’t.

I just did this for what will hopefully be a book chapter on our Divided Education - Divided Citizens research project with NEPC. Explanation further below for anyone more interested in the actual topic ;-) About the graphic: I like raw-...

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Students in predominantly ethnic minority classes want segregated education very much. The others don’t.

October 7, 2010
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Students in predominantly ethnic minority classes want segregated education very much. The others don’t.

I just did this for what will hopefully be a book chapter on our Divided Education – Divided Citizens research project with NEPC. Explanation further below for anyone more interested in the actual topic About the graphic: I like raw-data plots like this, made possible by Hadley Wickhams’s amazing ggplot2 package for the stats package

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The ARIMAX model muddle

October 4, 2010
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The ARIMAX model muddle

There is often confusion about how to include covariates in ARIMA models, and the presentation of the subject in various textbooks and in R help files has not helped the confusion. So I thought I’d give my take on the issue. To keep it simple, I will only describe non-seasonal ARIMA models although the ideas

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R Beginner’s Guide Book Update 10/1/2010

October 1, 2010
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R Beginner’s Guide Book Update 10/1/2010

Update: Statistical Analysis with R is now available!I recently submitted the final drafts of all chapters of my R Beginner's Guide book, which is to be published through Packt. The official publishing timeline is set to December 2010, although the boo...

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R Beginner’s Guide Book Update 10/1/2010

October 1, 2010
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R Beginner’s Guide Book Update 10/1/2010

Update: Statistical Analysis with R is now available!I recently submitted the final drafts of all chapters of my R Beginner's Guide book, which is to be published through Packt. The official publishing timeline is set to December 2010, although the boo...

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Example 8.7: Hosmer and Lemeshow goodness-of-fit

September 28, 2010
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Example 8.7: Hosmer and Lemeshow goodness-of-fit

The Hosmer and Lemeshow goodness of fit (GOF) test is a way to assess whether there is evidence for lack of fit in a logistic regression model. Simply put, the test compares the expected and observed number of events in bins defined by the predicted p...

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Example 8.6: Changing the reference category for categorical variables

September 21, 2010
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Example 8.6: Changing the reference category for categorical variables

How can we change the reference category for a categorical variable? This question comes up often in a consulting practice.When including categorical covariates in regression models, there is a question of how to incorporate the categories. One simpl...

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