search for: negbinomi

I'm having some difficulty with graphing outputs of a GLM model I've been working. I have count data for both my predictor (only 1) and response variables, and I have pseudoreplication which I've modeled as a random effect. The odTest() from pscl:: indicated that the negative binomial distribution fit better than Poisson, and I then proceeded by estimating theta from glm.nb. My

All, I have some data on parasites on apple leaves and want to do a goodness of fit test to a Poisson distribution. This seems to do it: mites <- c(rep(0,70), rep(1,38), rep(2,17), rep(3,10), rep(4,9), rep(5,3), rep(6,2), rep(7,1)) tab <- table(mites) NSU <- length(mites) N <-

...ng to get what I want: I need to know how the number of required trials to get a certain number of successes. By example: How many trials do I need to have 98% probability of 50 successes, when the a priory probability is 0.1 per trial. The Negative binomial function may do the job (not sure): NegBinomial {stats} The Negative Binomial Distribution Description Density, distribution function, quantile function and random generation for the negative binomial distribution with parameters size and prob. Usage dnbinom(x, size, prob, mu, log = FALSE) pnbinom(q, size, prob, mu, lower.tail = TRUE, log.p =...

...omial GLMs rnegbin Simulate Negative Binomial Variates theta.md Estimate theta of the Negative Binomial gam.neg.bin GAMs with the negative binomial distribution dnb2 Density for negative binomial, used in mmlcr theta.mmmod Estimate theta of the Negative Binomial by Moments NegBinomial The Negative Binomial Distribution ezinb The expected value of the censored zero-inflated negative binomial model Thanks, Reza [[alternative HTML version deleted]]

...) which returns 0 for n<1. -thomas ---------- Forwarded message ---------- Date: Thu, 08 Feb 2001 17:10:23 +0000 From: Yudi Pawitan <yudi@stat.ucc.ie> To: Mark Myatt <mark@myatt.demon.co.uk> Cc: R-Help <r-help@stat.math.ethz.ch> Subject: Re: [R] Goodness of fit to Poisson / NegBinomial Sorry, Mark, the program worked for Rw1011, but this is what happened in Rw1021: > dnbinom(0:5,.9,.4) [1] 0.4383833 0.0000000 0.0000000 0.0000000 0.0000000 0.0000000 #wrong!! while, the correct result from Rw1011 is: > dnbinom(0:5,.9,.4) [1] 0.43838329 0.23672698 0.13493438 0.078261...

...and edit src/library/base/R/distn.R and the MANY documentation files (where necessary) Beta.Rd Binomial.Rd Cauchy.Rd Chisquare.Rd Exponential.Rd F.Rd GammaDist.Rd Geometric.Rd Hypergeometric.Rd Logistic.Rd Lognormal.Rd NChisquare.Rd NegBinomial.Rd Normal.Rd Poisson.Rd T.Rd Uniform.Rd Weibull.Rd in src/library/base/man/*.Rd ------- Thanks in advance! Martin -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-devel mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html...

...perspective. Negative binomial regression provides a somewhat extreme example of existing overlap between packages, with the scope that this creates for confusing users, especially as the notation is not consistent between these different implementations. In addition to MASS::glm.nb(), note msme::negbinomial(), aod::negbin() and gamlss::gamlss(). The gamlss function fits two different types of NB model, either family = NBI (quadratic; var = mu(1 + sigma * mu)) as I think for all the functions above, or family=NBII (linear; var = mu(1 + sigma)). Also note the somewhat special purpose function glmnb...

Dear R users, I am trying to fully understand the difference between estimating overdispersion with glm.nb() from MASS compared to glm(..., family = quasipoisson). It seems that (i) the coefficient estimates are different and also (ii) the summary() method for glm.nb suggests that overdispersion is taken to be one: "Dispersion parameter for Negative Binomial(0.9695) family taken to be

...Negative Binomial Variates > theta.md > Estimate theta of the Negative Binomial > gam.neg.bin > GAMs with the negative binomial distribution > dnb2 > Density for negative binomial, used in mmlcr > theta.mmmod > Estimate theta of the Negative Binomial by Moments > NegBinomial > The Negative Binomial Distribution > ezinb > The expected value of the censored zero-inflated negative binomial model > > > > Thanks, > > Reza > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help@...

Hi, I was wondering if someone can help me interpret the results of running weibreg. I run the following and get the following R output. > weibreg(Surv(time, censor)~covar) fit$fail = 0 Call: weibreg(formula = Surv(time, censor)~covar) Covariate Mean Coef Rel.Risk L-R p Wald p covar 319.880 -0.002 0.998 0.000 log(scale) 0.000 8.239

...unction mccullagh89 McCullagh (1989) Distribution Family Function mckaygamma2 McKay's Bivariate Gamma Distribution micmen Michaelis-Menten Model multinomial Multinomial Logit Model nakagami Nakagami Distribution Family Function negbinomial Negative Binomial Distribution Family Function normal1 Univariate normal distribution paralogistic Paralogistic Distribution Family Function pareto1 Pareto and Truncated Pareto Distribution Family Functions paretoIV...

There is a problem with `rpois'. It does seem to take care about the order of the arguments. This is an example: > rpois(n=1,lambda=2) [1] 3 > rpois(lambda=2,n=1) [1] 2 0 It obviously uses the first argument as the number of samples to be drawn, which is wrong. I used Version 0.49 Beta (April 23, 1997). Fredrik

There is a problem with `rpois'. It does seem to take care about the order of the arguments. This is an example: > rpois(n=1,lambda=2) [1] 3 > rpois(lambda=2,n=1) [1] 2 0 It obviously uses the first argument as the number of samples to be drawn, which is wrong. I used Version 0.49 Beta (April 23, 1997). Fredrik

...lib/R/library/base/R-ex/Math.R action: create D: file: /usr/local/lib/R/library/base/R-ex/Memory.R action: create D: file: /usr/local/lib/R/library/base/R-ex/NA.R action: create D: file: /usr/local/lib/R/library/base/R-ex/NULL.R action: create D: file: /usr/local/lib/R/library/base/R-ex/NegBinomial.R action: create D: file: /usr/local/lib/R/library/base/R-ex/Normal.R action: create D: file: /usr/local/lib/R/library/base/R-ex/OrchardSprays.R action: create D: file: /usr/local/lib/R/library/base/R-ex/PlantGrowth.R action: create D: file: /usr/local/lib/R/library/base/R-ex/Platform...

...html latex example Math text html latex example Memory text html latex example NA text html latex example NULL text html latex example NegBinomial text html latex example Normal text html latex example OrchardSprays text html latex example Paren text html latex example PkgUtils tex...