Huisman–Olff–Fresco models
So called Huisman–Olff–Fresco models (HOF models) are a hierarchical set of 5 models with increasing complexity, designated for fitting unimodal species response curves on ecological gradient.
External links
The models are first presented in Huisman J., Olff H. & Fresco L.F.M. (1993). A hierarchical set of models for species response analysis. Journal of Vegetation Science, 4, 37-46
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Oksanen's introduction of HOF models, and software to compute them
extended (7 models including bimodal) HOF models , see Jansen F. & Oksanen J. (2013) How to model species responses along ecological gradients - Huisman-Olff-Fresco models revisited. Journal of Vegetation Science 24: 1108–1117.
