Standardizing / Normalizing environmental variables

[Caitlin Laidlaw]

Hi Everyone, 

I am wondering if I need to standardize/normalize my environmental variables prior to running ENMEval (to the same units, range, etc.)? I know this is common and often required in other sort of modelling when you want to compare the contribution of variables but never see this discussed in Maxent.

I found an old discussion post where someone mentioned Maxent already standardizes our predictor variables for us between 0-1, but can't seem to find this written anywhere in a published papers or manuals. There must be something simple I am missing here....

Thanks!

 

[Jamie M. Kass]

Yes, from what I understand maxent.jar and maxnet both standardize the predictor variables before modeling, then converts the values back for any results. You are also correct that it is hard to find this documented anywhere, even in the "Brief Tutorial" by Steven Philips. However, as the code is open now, its possible to go in there and verify.

Jamie