Abstract
Calculating a sample unit × trait matrix provides a flexible first step in analyzing the relationships between species traits and explanatory variables. This matrix is obtained by multiplying a sample unit × species matrix by a species × trait matrix, but the content of the resulting matrix depends on whether and how traits are standardized and whether or not the multiplication is followed by a weighted averaging step. To maximize versatility of the SU × trait matrix, including comparability among traits, and usability with a wide range of distance measures, we recommend first standardizing traits by min-to-max, then calculating abundance-weighted trait averages in each sample unit.
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Abbreviations
- SU:
-
Sample Unit
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McCune, B. The front door to the fourth corner: variations on the sample unit × trait matrix in community ecology. COMMUNITY ECOLOGY 16, 267–271 (2015). https://doi.org/10.1556/168.2015.16.2.14
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DOI: https://doi.org/10.1556/168.2015.16.2.14