[R] mixed-effects survival

Hi, What R libraries should I use to implement mixed effects models with continuous time and discrete-time survival data? What if I have two crossed random effects? I'd appreciate any help. Regards, Hakan Demirtas [[alternative HTML version de

[R] mixed effects models for grouped time survival data

How do I fit a mixed effects model with two crossed random effects for grouped time survival data? I tried coxme with no luck. Suppose that y is survival time, uncens is censoring indicator, trt is treatment below. ran.eff1 and ran.eff2 below are two crossed random effects. This way, it wou

[R] tetrachoric correlations

, Hakan Demirtas [[alternative HTML version deleted]] __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self

[R] sinusoidal relationship

Hi, Suppose x and y are vectors whose elements are known. I know that there is a sinusoidal relation between them. In other words, y=a*sin(bx) where b is probably a function of pi. How do I find a and b in R? Hakan [[alternative HTML version deleted]] _

[R] polygamma or Hurwitz zeta function

Hi, Is there any R library that is capable of handling polygamma function (Hurwitz zeta function also works)? I am aware of digamma(0 and trigamma(), but could not find more advanced versions. I'd appreciate any help. Hakan Demirtas __ R-h

[R] how do I make a correlation matrix positive definite?

above-mentioned function seem to mess up the diagonal entries. [I haven't seen this complication, but obviously all entries must remain in (-1,1) range after conversion.] Any R tools to handle this? I'd appreciate any help. Hakan Demirtas [[alternative HTML versi

Re: [R] how do I make a correlation matrix positive definite?

restandardize the matrix to get a pos def correlation matrix. Jeremy On 21 October 2010 15:50, HAKAN DEMIRTAS wrote: Hi, If a matrix is not positive definite, make.positive.definite() function in corpcor library finds the nearest positive definite matrix by the method proposed by Higham (198

[R] correlated data

Hi, Is there an R library that has the same functionalities of Splus7.0+ library correlatedData? I'd appreciate any input. Hakan Demirtas [[alternative HTML version deleted]] __ R-help@r-project.org mailing list https://stat.ethz.ch/ma

Re: [R] correlated data

(1993) but allowing for nested random effects. The within-group errors are allowed to be correlated and/or have additional heteroscedastic patterns. Regards, Hakan Demirtas __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help

[R] Proportional odds ordinal logistic regression models with random effects

I am trying to incorporate random effects (random intercept is good enough) to a proportional odds logistic regression model for ordinal outcomes. Could lme4 do this? I'd appreciate any input. Hakan Demirtas __ R-help@r-project.org mailing