Re: [R] Zero-inflated regression models: predicting no 0s

2011-06-03 Thread Michael Dewey
At 18:10 02/06/2011, geojs wrote: Thanks for the quick reply, I understand that the predict(zip1A, type = "response") command is computing the fitted_means and these are different than the probabilities predict(zip1A, type = "prob"). Although, according to Martin (2005), the highest probabilitie

Re: [R] Zero-inflated regression models: predicting no 0s

2011-06-03 Thread Achim Zeileis
On Thu, 2 Jun 2011, geojs wrote: Thanks for the quick reply, I understand that the predict(zip1A, type = "response") command is computing the fitted_means and these are different than the probabilities predict(zip1A, type = "prob"). Yes. One evaluates the probability density function, and th

Re: [R] Zero-inflated regression models: predicting no 0s

2011-06-02 Thread geojs
Thanks for the quick reply, I understand that the predict(zip1A, type = "response") command is computing the fitted_means and these are different than the probabilities predict(zip1A, type = "prob"). Although, according to Martin (2005), the highest probabilities do not simply lead to the true co

Re: [R] Zero-inflated regression models: predicting no 0s

2011-06-01 Thread Achim Zeileis
On Tue, 31 May 2011, Jean-Simon Michaud wrote: Hi all, First post for me here, but I have been reading on the forum for almost two years now. Thanks to everyone who contributed btw! I have a dataset of 4000 observations of count of a mammal and I am trying to predict abundance from a inflated-

[R] Zero-inflated regression models: predicting no 0s

2011-05-31 Thread Jean-Simon Michaud
Hi all, First post for me here, but I have been reading on the forum for almost two years now. Thanks to everyone who contributed btw! I have a dataset of 4000 observations of count of a mammal and I am trying to predict abundance from a inflated-zero model as there is quite a bit of zeros