I’ve spent so many years using and broadcasting my love for R and using Python quite minimally. Having read recently about machine learning in Python, I decided to take on a fun little ML project using Python from start to … Continue reading →

Consider planning a clinicial trial where patients are randomized in permuted blocks of size four to either a 'control' or 'treatment' group. The outcome is measured on an 11-point ordinal scale (e.g., the numerical rating scale for pain). It may be reasonable to evaluate the results of this trial using a proportional odds cumulative logit

I've created an easy to use R script that will import your data, and performs and writes up a state-of-the-art dependent or independent t-test. The goal of this script is to examine whether more researcher-centered statistical tools (i.e., a one-click analysis script that checks normality assumptions, calculates effect sizes and their confidence intervals, creates good figures,...

I often get asked how to fit different multilevel models (or individual growth models, hierarchical linear models or linear mixed-models, etc.) in R. In this guide I have compiled some of the more common and/or useful models (at least common in clinical psychology), and how to fit them using nlme::lme() and lme4::lmer(). I will cover the common two-level random...

Geomorph users,When starting out in a geometric morphometrics study, the common questions are ones of repeatability and measurement error.How much of the variation in the Procrustes residuals is due to human (digitizing) error? How much is du...

Did you know that geomorph is not just for landmark-based geometric morphometric (shape) data?We are committed to providing statistical tools for multivariate AND multidimensional morphometric data.As laid out in the recent series of papers on Phylogenetic Comparative Methods for high-dimensional data (Adams 2014a, Adams 2014b, Adams 2014c, Adams & Felice 2014), harnessing the R-mode – Q-mode equivalency as first shown...

Yesterday, I did upload a post where I tried to show that “standard” regression models where not performing bad. At least if you include splines (multivariate splines) to take into accound joint effects, and nonlinearities. So far, I do not discuss the possible high number of features (but with boostrap procedures, it is possible to assess something related to...

The APS Observer has just published a profile of JASP, a graphical user interface designed to make statistics easier. It includes Bayesian procedures by means of the R and the BayesFactor package. From the article: JASP distinguishes itself from S...

e-mails with the latest R posts.

(You will not see this message again.)