distTestData | R Documentation |
Artificial data for counts of 32 species at 5 sites.
data(distTestData)
A matrix with 5 rows (sites), labelled A-B, and 32 columns (species).
Sites A, B and C each have 16 species and 158 individuals.
Sites A and B have the same species, but the numbers of each are different.
Site C has a completely different set of 16 species, but the same number of individuals.
Site D has the same species in the same proportions as A, but twice the number of individuals.
Site E has 32 species and 316 individuals.
Artificial data.
data(distTestData) # Display the data: print(t(distTestData)) distShell(distTestData, distJaccard) # A B C D # B 0.0 # C 1.0 1.0 # D 0.0 0.0 1.0 # E 0.5 0.5 0.5 0.5 # Jaccard index ignores counts, so sees AB, AD and BD as identical (zero distance). round(distShell(distTestData, distMorisitaHorn), 2) # A B C D # B 0.89 # C 1.00 1.00 # D 0.00 0.89 1.00 # E 0.33 0.93 0.33 0.33 # Morisita-Horn index considers proportions, so AD are identical but not AB or BD. round(distShell(distTestData, distBrayCurtis), 2) # A B C D # B 0.84 # C 1.00 1.00 # D 0.33 0.84 1.00 # E 0.33 0.89 0.33 0.50 # Bray-Curtis index is affected by abundance as well as proportions, so AD are no longer identical. # Site C only overlaps with D, so AC, BC and CD are 1.00 for all indices. # Site E overlaps with all the others, so AE, BE, CE and DE all lie between 0 and 1 for all indices.
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.