Search Archives

An embedded and charset-unspecified text was scrubbed... Name: not available URL: <https://stat.ethz.ch/pipermail/r-sig-ecology/attachments/20120705/4ac4470e/attachment.pl>

Thanks Jason, The cumulative link modeling (clm) in the ordinal package seems to be exactly what we needed. I found an excellent walk-through to this analysis at: http://cran.r-project.org/web/packages/ordinal/vignettes/clm_tutorial.pdf...

Hello Mike, One approach may be to convert your coordinates to a custom continuous equidistant conic projection with a central meridian near the center of your coordinates. This should help minimize errors in distances calculated across a large area. Hope...

Dear R for ecology experts, I have found many discussions online about blocking and nesting in adonis, but no answers for blocking. I have community data with abundances within 42 aquatic genera (final.fd[,9:36]) from 2 types of...

/*----------------------------------------------------------------------------------------------------------------------------- Jeffrey D. Holland, Professor jdhollan at purdue.edu Dept. of Entomology, Purdue University 765 / 494-7739 Section Editor, Current Landscape Ecology Reports Skype: ecobugprof Associate Editor, Landscape Ecology www.entm.purdue.edu/landscapeecology Fellow of the Indiana Academy of Science...

Hello Mahnaz, Longitude is often expressed as distance or angle east of the prime meridian, so negative means it is west. If I am reading your question correctly, you are wondering how to change the longitude to make it negative...

Dear Manuel, Have a look at the Dryad data repository, datadryad.org. You can search around for many ecological data sets. I have used this a lot for similar classes. You can also read the associated paper for the data...

Hello Pete, You could include the sine and cosine of the angles. A good book on this kind of analysis: Fisher, N.I. 1993. Statistical Analysis of Circular Data. Cambridge Univ. Press. To make this closer to exposure, perhaps you...

Dear Mark, Gower does seem to the correct dissimilarity metric based upon your variables. This will return a dissimilarity matrix that I believe you can use to calculate the functional diversity indices, by base code and likely by FD package...

Dear Ecologists, A student of mine is using vegan to create a Gower?s dissimilarity matrix between species of wood-boring beetles based upon ecological traits. One trait we are using is the Family of host trees used as hosts...

Hello Tenan, If very good graphics are the main goal, one option is to use POV-Ray to plot the planes. I know POV-Ray and R talk to each other, but I have had luck simply taking equations output...

Dear R Ecologists, Does anyone have ideas on how to compare "distributions" (binned count values) between 2 treatments when there are several paired replicates? I have data on the tolerance to poor water conditions of organisms in two types of...