Species Group Summaries for Bird Conservation Regions
Select a time period, region, and species group, and this program
will produce a summary of trends. The summary includes:
Number of species,
Proportion of species with positive trend estimates,
Proportion of species with significant (+ and -) trend estimates, and
List of species and their trend estimates.
We also provide some estimates of mean trend and a ranking of species
from most extreme decline to most extreme increase, using the procedures
given in Link and Sauer 1996. These results adjust
estimates for relative precision, and you can estimate:
Precision weighted mean trend (called a prior mean),
95% Confidence interval on the prior mean, and
Rankings of species based on an precision-weighted reordering
of the estimates.
ver 2005.0, 16 January 2006, Authors: J. R. Sauer and J. E. Hines.
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Although these data have been processed successfully on a
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expressed or implied is made regarding the accuracy or utility of
the data on any other system or for general or scientific purposes,
nor shall the act of distribution constitute any such warranty.
This disclaimer applies both to individual use of the data and
aggregate use with other data. It is strongly recommended that
these data are directly acquired from a Biological Resource Division
server, and not indirectly through other sources which may have
changed the data in some way. It is also strongly recommended that
careful attention be paid to the contents of the metadata file
associated with these data. The Biological Resource Division shall
not be held liable for improper or incorrect use of the data
described and/or contained herein.
So, these data are provided
"as is" and without
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