środa, 20 lutego 2013

Some big news about MAXENT


dla zainteresowanych modelowaniem - wpis Davida Wartona, na blogu Methods in Ecology and Evolution:

"I’m sure by now you’ve heard of MAXENT. Have you got the impression that it’s some revolutionary new method that sits apart from classical methods like GLM? If so I have some big news for you.
MAXENT, as implemented in presence-only analyses, has recently been shown to be exactly mathematically equivalent to a GLM, more specifically, to a Poisson regression (also known as “log-linear modelling”). Poisson regression is a standard method from statistics that is well understood and implemented on most statistical packages, e.g. R users can type glm(formula, family=”poisson”). This equivalence result is big news because a modern icon of ecological modelling has now been revealed to be equivalent to an older method that went out of fashion some time ago… it’s a bit like Beyonce taking off a face mask at the Superbowl to reveal that all along it’s actually been… Janet Jackson!"

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Jakub Szymkowiak

1 komentarz:

  1. Przemek Chylarecki22 lutego 2013 01:01

    Słowa, słowa (maxent=glm) versus twarde wyniki "We demonstrate that maxent produces extreme under-predictions when compared to estimates produced by logistic regression which uses the full (presence/absence) data set. We note that maxent predictions are extremely sensitive to specification of the background prevalence, which is not objectively estimated using the maxent method" (Royle et al 2012, MEE).