Dear all,

I am using the function wi of the package adehabitat to calculate selection
ratios. I have the used and the available proportions for each "animal"
(6658), which are in fact fires that burn different land cover types (the
resources), thus I'm applying design III.

The formula is simple:

sr = widesIII(used, available, avknown=TRUE, alpha=0.05)

used=dataframe with proportion of used resources for each fire
available=dataframe with proportion of available resources for each fire
avknown=if the proportion is known (TRUE) or estimated
alpha=the level for the confidence intervals (95%)

I came across an error on a specific dataset which I don't really
understand; the same procedure was applied to other datasets that had the
same data format and it worked fine. In this case, it seems there is an
error related to the upper limit of the confidence interval (ICdiffupper),
but I cannot understand what is the problem with the data...

Error in if (ICdiffupper[i, j] < 0) sig[i, j] <- "---" :
  missing value where TRUE/FALSE needed

In case you have any suggestion, please let me know.

Thanks!

Sandra

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