Statistics + Beer = Comprehension - A goodness of fit test are a collection of statistical techniques used to summarize the differences between observed values and expected values. These tests can be used be used for hypothesis testing, testi...

Discriminant analysis is also applicable in the case of more than two groups. In the first post on discriminant analysis, there was only one linear discriminant function as the number of linear discriminant functions is , where is the number of dependent variables and is the number of groups. In... The post Discriminant Analysis of Several Groups appeared...

At the University of Utah, I teach the R lab that accompanies MATH 3070, “Applied Statistics I.”” None of my students are presumed to have any programming experience, and they never hesitate to remind me of that fact, especially when they are starting out. When I create assignments and pick problems, I often can write…Read more Where...

I'm happy to introduce an add-on package, pdfsearch, that adds the ability to do keyword searches on pdf files. This add-on package uses the excellent pdftools package from the ropensci project to read in pdf files and perform keyword searches based ch...

This is post #3 on the subject of linear regression, using R for computational demonstrations and examples. We cover here residuals (or prediction errors) and the RMSE of the prediction line. The first post in the series is LR01: Correlation. Acknowledgments: organization is extracted from: Freedman, Pisani, Purves, Statistics, 4th ed., probably the best book on statistical thinking...

Sometimes data may not be available in the csv file in the required format. Consider the following csv file, whose details are as follows – Four different treatments were given to four different groups of patients. Random samples of size 7 were selected from each group and blood levels of Hb percentage levels were measured … Continue...

Written by Frank E Harrell Jr (first published here) A major new version of the rms package is now on CRAN. The most user-visible changes are: – interactive plotly graphic methods for model fits. The best example of this is survplot for npsurv (Kaplan-Meier) estimates where the number of risk pop up as you hover over the curves, and you...

Raccoon is a free web-book about Statistical Models with R. It's the collection of twenty years of notes, exercises and concepts working with statistics and R. This is the second section of the second chapter, about 2-sample t-test and paired t.
The post Raccoon | Ch 2.2 – 2 sample t-test and paired t appeared first on

A few months ago I wrote about my first solo author submission to the R Journal entitled, “A Simple Guide to S3 Methods”. Unfortunately the article didn’t make it to publication on the R Journal, but admittedly that might have been a bit of a lon...

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