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...

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...

Anscombe’s quartet comprises four datasets that have nearly identical simple statistical properties, yet appear very different when graphed. Each dataset consists of eleven (x,y) points. They were constructed in 1973 by the statistician Francis Anscombe to demonstrate both the importance of graphing data before analyzing it and the effect of outliers on statistical properties.Let’s load and view...

On of the most frequently asked questions about the BayesFactor package is how to do multiple comparisons; that is, given that some effect exists across factor levels or means, how can we test whether two specific effects are unequal. In the next two posts, I'll explain how this can be done in two cases: in Part 1, I'll cover...