An embedded and charset-unspecified text was scrubbed... Name: not available URL: <https://stat.ethz.ch/pipermail/r-help/attachments/20110221/7073a966/attachment.pl>
Species accumulation curves with differential sampling effort
5 messages · Vanessa Francisco, David Winsemius, Dennis Murphy +2 more
On Feb 21, 2011, at 12:38 PM, Vanessa Francisco wrote:
Hello! I'm a PhD student working with coral reef fish diversity in Mexico.
Are you hiring?
I want to do species accumulation curves but I have differential sampling effort for each "sample". Do you know or have developed an R script that consider the differential effort of each sample? PRIMER
... not familiar with that package.
and other programs use each pack of species as a replica without the possibility of telling the program that the first group of species (sample) was collected during a 30 minutes dive and the second group (sample) was taking after 60 minutes dive and so on.
If you were using a glm model with a a log(poisson) link, then adding an offset term that was equal to log(time) should sensibly incorporate the information for the differential effort.
I would really appreciate any kind of help! Best regards, Vanessa Francisco <"><
David Winsemius, MD West Hartford, CT
An embedded and charset-unspecified text was scrubbed... Name: not available URL: <https://stat.ethz.ch/pipermail/r-help/attachments/20110221/14b7d92b/attachment.pl>
Vanessa Francisco <vanewagen <at> gmail.com> writes:
Hello! I'm a PhD student working with coral reef fish diversity in Mexico. I want to do species accumulation curves but I have differential sampling effort for each "sample". Do you know or have developed an R script that consider the differential effort of each sample? PRIMER and other programs use each pack of species as a replica without the possibility of telling the program that the first group of species (sample) was collected during a 30 minutes dive and the second group (sample) was taking after 60 minutes dive and so on. I would really appreciate any kind of help!
Vanessa, I speak only for the vegan package: I don't know if there is solution elsewhere in R. I can certainly say that this cannot be done in vegan. However, it seems like this could be "easily" implemented in some accumulation methods, but not with all. Is this weighted SAC published somewhere? If I "re-invent" it, I'd like to see what others have done. How keenly and urgently you need this? This will require a bit work since the structure of function needs changes although the idea is simple, and I'd like to know if that work is of any use to anyone before starting. Of course, if this already is in R, I won't do this. Cheers, Jari Oksanen
An embedded and charset-unspecified text was scrubbed... Name: not available URL: <https://stat.ethz.ch/pipermail/r-help/attachments/20110222/e80f439f/attachment.pl>