Comparison of NPMR in HyperNiche with other methods of habitat modeling


 

 

Comparison of GAM or GAMs (Generalized additive models) and NPMR:
  • GAMs and NPMR share the use of smoothing functions. Individual terms are combined additively in GAMs and multiplicatively in NPMR.

  • GAMs model interactions by adding specific terms, while they are modeled automatically with a multiplicative kernel function in NPMR.

  • Commercial software for GAMs is more expensive and harder to use than NPMR in HyperNiche.

  • GAMs have no theoretical basis for additive terms in controlling species response functions, while NPMR has an explicit theoretical and biological foundation as a statistical representation of Shelford’s Law of Tolerance.

Comparison of logistic regression and NPMR:
  • In logistic regression (a form of generalized linear model, GLM) the analyst must specify in advance the form of the response function for each predictor and their interactions (e.g. sigmoid, hump-shaped, linear), even when the analyst has no theoretical basis for choosing one response type over another, while NPMR is open to any form of response function.

  • Interactions must be modeled explicitly with logistic regression, by adding specific terms, while they are modeled automatically in NPMR.

  • Commercial software for logistic regression is more expensive and harder to use than NPMR in HyperNiche.

Comparison of MARS (Multivariate adaptive regression splines) and NPMR:
  • MARS fits separate splines to different intervals of the predictors, while NPMR applies a multidimensional kernel smoother.

  • Both MARS and NPMR can fit response surfaces that differ fundamentally in shape in different parts of the surface.

  • Both MARS and NPMR seek the best model by a numerically intensive and exhaustive search through the domain of possible models.

  • Both MARS and NPMR are well suited to modeling interactions. NPMR does so automatically, while MARS users request consideration of interactions up to a specified level.

  • Commercial software for GAMs is more expensive and harder to use than NPMR in HyperNiche.

  • MARS has no theoretical basis in the biology of species response to habitat factors, while NPMR has an explicit theoretical and biological foundation as a statistical representation of Shelford’s Law of Tolerance.