Wednesday, 27 August 2014

R-lab on Mixed models in Ecology

Hi guys,

This Friday, 29th August at 2pm, there will be in an R-lab on mixed models in ecology, a topic which many of you are interested in digging deeper into. I've set up too links to dropbox for the slides as well as a csv file which we will be playing with (dataset courtesy of Sylvia Hay =D)


PDF slides
Example 1: Bird counts
Example 2: Nested design dataset

(Corrected) code for bird analysis

Yours non-significantly,

Monday, 4 August 2014

Sexy, unconstrained models all ready for you to play with!

When trying to visualize how sites vary in terms of species composition, for too long ecologists have been using distance-based methods of unconstrained ordination such as NMDS and CA, with little but precedence to guide them on what dissimilarity measure to use and what transformation and/or standardization to apply.

In collaboration with some folks in New Zealand and Finland, we've been working on a couple of model-based approaches to unconstrained ordination, which offer several advantages such as explicitly accounting for key properties of the data and model variable tools to select key aspects of the analysis. Simulations also show our proposed methods either perform the same or way better than distance-based approaches at the getting the ordinations correct!

Check out our manuscript, now available for early view at: