Posts Tagged ‘ summary ’

Example 9.9: Simplifying R using the mosaic package (part 1)

October 13, 2011
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Example 9.9: Simplifying R using the mosaic package (part 1)

While both SAS and R are powerful systems for statistical analysis, they can be frustrating to new users or those learning statistics for the first time. RThe mosaic package is designed to help simplify the interface for such new users, while allowing ...

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Manual variable selection using the dropterm function

May 12, 2010
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Manual variable selection using the dropterm function

When fitting a multiple linear regression model to data a natural question is whether a model can be simplified by excluding variables from the model. There are automatic procedures for undertaking these tests but some people prefer to follow a more manual approach to variable selection rather than pressing a button and taking what comes

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Analysis of Covariance – Extending Simple Linear Regression

April 28, 2010
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Analysis of Covariance – Extending Simple Linear Regression

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 to fit a separate linear

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Simple Linear Regression

April 23, 2010
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Simple Linear Regression

One of the most frequent used techniques in statistics is linear regression where we investigate the potential relationship between a variable of interest (often called the response variable but there are many other names in use) and a set of one of more variables (known as the independent variables or some other term). Unsurprisingly there

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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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The Life Scientists at FriendFeed: 2009 summary

December 23, 2009
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The Life Scientists at FriendFeed: 2009 summary

It’s Christmas Eve tomorrow and so I declare the year over. My Christmas gift to you is a summary of activity in 2009 at the FriendFeed Life Scientists group. It’s crafted using R + Ruby, with raw data and some code snippets available. If you want to see the most popular items from the group

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