Making better MAXENT models of species distributions: complexity, overfitting, and evaluation
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چکیده
Appendix S1: Procedure for masking environmental variables. For the masked geographically structured approach, we took background environmental data only from the areas of the bins used in model calibration (Anderson & Raza, 2010). To do so, we ‘masked’ out the area corresponding to the bin being withheld for evaluation by using a dummy variable. The dummy variable had a value of zero in the regions corresponding to the calibration bins and no data for the region corresponding to the bin of localities with which the model was to be evaluated. When the resulting model was projected to the full study region to allow for evaluation, the dummy variable was assigned a value of zero for the full study region.
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