Count data

classic Classic list List threaded Threaded
2 messages Options
Reply | Threaded
Open this post in threaded view
|

Count data

mujeeb rahman
Hi All
I am currently working on soil fauna, abundance of soil macrofauna
from different habita. Due to the overdispersion, the abundance (count
data) contains many extreme values (zeroes as well as 100s..!!!).

The data contains abundance soil fauna from 15 landuse type (coming
under four ecosystems), for each landuse type I have 4 spatially
different plots. I each plot 4 random soil monoliths are taken and
soil fauna were counted.

I think it is a nested model, monoliths are nested in plot, plots are
nested in landuse. Poisson, NBD of Zeroinflated NBD models may be
appropriate, but must be validated. Is there were any provision to
conduct such analysis in R?. If so please give me details of package
or examples, if any.

A line of communication is greatly appreciated, which is worthful..

Thanking all
Mujeeb Rahman P
KFRI, Peechi, Thrissur, Keraka, India

_______________________________________________
R-sig-ecology mailing list
[hidden email]
https://stat.ethz.ch/mailman/listinfo/r-sig-ecology
Reply | Threaded
Open this post in threaded view
|

Re: Count data

Thomas Petzoldt
Hi Mujeeb,

I'm not yet completely sure about the particular question of your work,
but you may read the following paper that appeared in the Journal of
Statistical Software two months ago. It describes a package for
organizing and processing ecological count data and contains also an
overview over other ecologically relevant packages:

Solymos, P. (2009) Processing Ecological Data in R with the mefa
Package. Journal of Statistical Software Vol. 29, Issue 8, Feb 2009.
http://www.jstatsoft.org/v29/i08

Note that JSS is an ISI listed OpenAccess Journal, so you can access the
PDFs freely without cost.

Hope it helps.

Thomas Petzoldt


mujeeb rahman wrote:

> Hi All
> I am currently working on soil fauna, abundance of soil macrofauna
> from different habita. Due to the overdispersion, the abundance (count
> data) contains many extreme values (zeroes as well as 100s..!!!).
>
> The data contains abundance soil fauna from 15 landuse type (coming
> under four ecosystems), for each landuse type I have 4 spatially
> different plots. I each plot 4 random soil monoliths are taken and
> soil fauna were counted.
>
> I think it is a nested model, monoliths are nested in plot, plots are
> nested in landuse. Poisson, NBD of Zeroinflated NBD models may be
> appropriate, but must be validated. Is there were any provision to
> conduct such analysis in R?. If so please give me details of package
> or examples, if any.
>
> A line of communication is greatly appreciated, which is worthful..
>
> Thanking all
> Mujeeb Rahman P
> KFRI, Peechi, Thrissur, Keraka, India
>
> _______________________________________________
> R-sig-ecology mailing list
> [hidden email]
> https://stat.ethz.ch/mailman/listinfo/r-sig-ecology
>


--
Thomas Petzoldt
Technische Universitaet Dresden
Institut fuer Hydrobiologie        [hidden email]
01062 Dresden                      http://tu-dresden.de/hydrobiologie/
GERMANY

_______________________________________________
R-sig-ecology mailing list
[hidden email]
https://stat.ethz.ch/mailman/listinfo/r-sig-ecology