I recently decided to create two blogs as outlets for my research. The first (The Richness of Life) focuses more on the organisms I work with as an ecologist and my general interest as a student of natural history. This blog on Quantitative...

I am a contributor to the optmatch and the RItools packages for R. These two packages are separate, but complimentary. Both packages provide tools for adjusting observational data to exhibit “balance” on observed covariates. In a randomized control trial, treatment and control groups should have identical distributions over all covariates, observed and unobserved. Matching provides a...

Two way analysis of variance models can be fitted to data using the R Commander GUI. The general approach is similar to fitting the other types of model in R Commander described in previous posts. Fast Tube by Casper The “Statistics” menu provides access to some analysis of variance models via the “Means” sub-menu: Multi-way ANOVA – the

One way analysis of variance models can be fitted to data using the R Commander GUI. The general approach is similar to fitting the other types of model in R Commander described in previous posts. Fast Tube by Casper The “Statistics” menu provides access to some analysis of variance models via the “Means” sub-menu: One-way ANOVA – the

OK, so, the title of this article is actually Do not log-transform count data, but, as @ascidacea mentioned, you just can’t resist adding the “bitches” to the end. Onwards. If you’re like me, when you learned experimental stats, you were taught to worship at the throne of the Normal Distribution. Always check your data and

Voter targeting for turnout is the process of scoring registered voters using demographic and electoral variables taken from voter lists and commercial databases. The score of all voters together is used to predict overall turnout, which determines the allocation of campaign resources and directs strategy for voter contact and communication. Targeting for turnout is a

The R programming language includes many abbreviations. Abbreviations exist in function names, argument names, and allowed values for arguments. This post expands on over 150 R abbreviations with the aim of making it easier for users new to R who are trying...

The R programming language includes many abbreviations. Abbreviations exist in function names, argument names, and allowed values for arguments. This post expands on over 150 R abbreviations with the aim of making it easier for users new to R who are trying...

Glancing perchance at the back of my Amstat News, I was intrigued by the SAS advertisement Bayesian Methods Specify Bayesian analysis for ANOVA, logistic regression, Poisson regression, accelerated failure time models and Cox regression through the GENMOD, LIFEREG and PHREG procedures. Analyze a wider variety of models with the MCMC procedure, a general purpose Bayesian