Comments on: One-way Analysis of Variance (ANOVA)

By: Ralph

Ralph — Sat, 02 Jul 2011 09:57:31 +0000

Hi Bob,

Thanks for your positive comments on the blog and I think that I will investigate the R package you mention (granova) as I am particularly interested in the visual display of information. Having learnt a lot about R from reading freely available resources from other people I hope to give something back to other people who are finding their feet while learning R. An additional benefit for me of this blog is that I don’t have to carry round a large stack of books on R!

Many thanks
Ralph

By: Bob Pruzek

Bob Pruzek — Fri, 24 Jun 2011 18:02:52 +0000

In case you might be interested, I (w/ a coauthor) have created a package called ‘granova’ for R (now in ver. 2.0), that creates particularly helpful graphics for four classes of ANOVA. Further, we have now completed a paper (submitted for publication) on Elemenatal Graphics that provides extended documentation for the functions in the package. I will send it to you upon request.
The reason I’m writing is that I’m particularly impressed w/ your superb website at wekaleamstudios and find it helpful in many ways in my teaching statistics w/ R. (My special concerns have to do w/ graphics and visualization of data; also propensity score analysis for which I have a package: PSAgraphics.)
Best, Bob Pruzek (Professor, Statistics, NY)

By: Ralph

Ralph — Fri, 12 Feb 2010 13:15:05 +0000

Romunov

The functions aov() and lm() can indeed be used to fit the same model and aov() has the advantage that when we summarise the fitted model object the output includes analysis of variance tables as the user might be expecting to see with the partitions based on the model terms.

Thanks for the suggesting about extending the blog post and I will look in to describing how to create graphs with means and confidence intervals and other usual ways to interrogate the model.

Ralph

By: Ralph

Ralph — Fri, 12 Feb 2010 12:57:16 +0000

Dear Duleep,

My intention is to convert the blog posts into pdf documents for easier consumption online and offline. As you can see from supplementary material section of the website I have (slowly) started this process with producing graphs of various different types. If there are particular statistical methods that you feel should be covered then that is useful for me to know where to focus efforts in blogging.

Ralph

By: romunov

romunov — Thu, 04 Feb 2010 11:28:51 +0000

Great post. Perhaps you could add how to plot confidence intervals on one’s plot.

I personally use aov() and draw the diagnostic plot of that model.

By: Duleep Kumar Samuel

Duleep Kumar Samuel — Thu, 04 Feb 2010 05:59:49 +0000

Dear Ralph, thanks for real good content. will you please compile your writings into a pdf , thanks with regards, Dr.D.K.Samuel, Ind Inst of Hort Research, Bangalore India