Dear all As part of an ongoing study on the ecomorphology of ant communities, I have obtained a matrix with 156 row (species) and 20 columns (several measurements of body shape) for 4 localities.
For each community, I calculated a matrix of Euclidean distances between all pairs of species. From this matrix, I extracted two measures of community structure: i) I identified the distance from a individual to its nearest neighbor (NND) in the morphological space and then calculated the averages of the NND (MNND); ii) the mean of the Euclidean distances (MED). NND and MED are of practical use in describing spatial relations between species. The results of Euclidean distance studies in each of the four localities were compared with each other for evidence repeating patterns. To determine wheter ou not the morphological arrangement of species in communities reflected internal organization, MNND and MED should be compared with randomly generated communities. It is possible to write a function in th boot package to evaluate the values of average nearest-neighbor distance and of the mean of Euclidean distances in randomly generated communities ? One set of 1000 random communities each with 78, 90, 100 and 102 species must be generaded from the pool of species (156 species). The only restrictions on species composition is that no species could be placed in a community more than once, and only rows values can be permuted. Sorry, I don't know how to define the statistic term in the boot() function from the boot library in R. I have studied the boot package, argument list of functions and the functions definition. Can someone point me the correct syntax? I would very much appreciate any help Best regards Rog�rio ______________________________________________ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
