[R] Are there any package for sub-sampling data

[Bruce Miller]

Hi all,

I need to sub sample some large data sets.
The problem is using complete data samples for bats that are ± data per 
1-minute time blocks using acoustic data collection and a method I 
published some time back. Miller, B. W. 2001. A method for determining 
relative activity of free flying bats using a new activity index for 
acoustic monitoring. Acta Chiropterologica. 3: 93-105.

I am convinced after analyzing complete data for each night to derive 
relative abundance and species compositions that the consultants who are 
doing wind power monitoring and ONLY using 5 to 10 minute sub samples 
for each hour like the first 5 or 10 minutes are missing especially eh 
rare species that have only a few occurrences so misleading results.

Anyone have any suggestions to a field ecologists who is not a dyed in 
the wool stats person on how to sub sample the data sets and robustly 
test this hypothesis?

Happy to co-author a paper if some one is interested as I have the data.

Cheers,

Bruce

-- 
Bruce W. Miller, Ph.D.
Conservation Ecologist
Neotropical Bat Projects


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