Publications by John Quick
R Tutorial Series: Regression With Categorical Variables
Categorical predictors can be incorporated into regression analysis, provided that they are properly prepared and interpreted. This tutorial will explore how categorical variables can be handled in R. Tutorial FilesBefore we begin, you may want to download the sample data (.csv) used in this tutorial. Be sure to right-click and save t...
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R Tutorial Series: Basic Polynomial Regression
Often times, a scatterplot reveals a pattern that seems not so linear. Polynomial regression can be used to explore a predictor at different levels of curvilinearity. This tutorial will demonstrate how polynomial regression can be used in a hierarchical fashion to best represent a dataset in R. Tutorial FilesBefore we begin, you may w...
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R Tutorial Series: R Beginner’s Guide and R Bloggers Updates
1/1/2011 Update: Tal Galili wrote an article that revisits the first year of R-Bloggers and this post was listed as one of the top 14. Therefore, I decided to make a small update to each section. I start by describing the initial series of tutorials that I wrote. A few more have been added since and even more planned in the upcoming year. As alwa...
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R Beginner’s Guide Book Update 4/28/2010
Update: Statistical Analysis with R is now available!I am writing to update you on the progress of my R Beginner’s Guide book, which is to be published through Packt. I have really gotten to work over the past couple months and have recently completed the first draft of the first half of the book. Right now, I am operating a few weeks ahead of ...
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R Beginner’s Guide Book Update 7/19/2010
Update: Statistical Analysis with R is now available!I am excited to announce that I have submitted the entire first draft of my R Beginner’s Guide book, which is to be published through Packt. The tenth and final chapter was submitted a full month ahead of schedule. The printed book could become available in as little as three to four months.B...
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R Tutorial Series: Labeling Data Points on a Plot
There are times that labeling a plot’s data points can be very useful, such as when conveying information in certain visuals or looking for patterns in our data. Fortunately, labeling the individual data points on a plot is a relatively simple process in R. In this tutorial, we will use the Calibrate package’s textxy function to l...
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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 book may release ahead of schedule if all continues to go well. Below is an updated list of the m...
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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 download the sample data (.csv) used in this tutorial. Be sure to right-click and save...
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R Beginner’s Guide Book Update: Statistical Analysis with R Released
In the final days of October, my beginner’s guide to R was released. The book’s official title is Statistical Analysis with R and it can be found on the Packt Publishing website. The primary focus of Statistical Analysis with R is helping new users become accustomed to R and empowering them to apply R to suit their own needs. No p...
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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 begin, you may want to download the sample data (.csv) used in this tutorial. Be su...
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