search for: ssv736

Hi, When modeling with negbin from the aod package, parameters for a given count y | lambda~Poisson(lambda) with lambda following a Gamma distribution Gamma(r, theta) are estimated. The intercept is called phi. Some other parameters may be also be estimated from factors in the data: the estimates returned for all these would be in accordance with the Value listing in the negbin entry in the aod

Hello, I'm trying to understand grofit's estimation of models, and fairly new to growth models generally. The data used by grofit consists of the vector of "experiments", that is the growth values for a vector of individuals measured at different times. Can I understand correctly that the program estimates parameters for the growth model based on a regression(linear or non

Hello, After putting together interaction code that worked for a single pair of interactions, when I try to evaluate two pairs of interactions( flowers*gopher, flowers*rockiness) my computer runs out of memory, and the larger desktop I use just doesn't go anywhere after about 20 minutes. Is it really that big a calculation? to start: mle2(minuslogl = Lily_sum$seedlings ~ dnbinom(mu = a,

...ilable > > Can anyone help me in this regard? > > Expecting your reply and thanks in advance. > > Warm regards > Fredrick. > > > > ------------------------------ > > Message: 11 > Date: Tue, 23 Mar 2010 19:22:02 +0700 > From: alexander russell <ssv736 at gmail.com> > To: r-help at r-project.org > Subject: Re: [R] estimation of parameters with grofit > Message-ID: > ??? <b6510ff51003230522p769e81f2yb9c69bc72d3eca67 at mail.gmail.com> > Content-Type: text/plain > > Hello again about grofit: > I've been looking...

Hello, I'd like to say that it's clear when an independent variable can be ruled out generally speaking; on the other hand in R's AIC with bbmle, if one finds a better AIC value for a model without the given independent variable, versus the same model with, can we say that the independent variable is not likely to be significant(in the ordinary sense!)? That is, having made a lot of

Hello, Is there a clearcut answer as to why R prints 'NA' sometimes instead of standard errors? mle2(minuslogl = nlikfun4, start = list(a = 1, c = 1, d = 0.2, b = 0.1, b1 = 0.1), method = "Nelder-Mead") Coefficients: Estimate Std. Error z value Pr(z) a 3.83845751 0.47320236 8.1117 4.993e-16 *** c 0.95545367 NA NA NA d -0.22509015 NA NA NA b 0.04260199 0.00743892 5.7269