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It's telling you that one or more of the grouping factors for the random-effect terms has less than three levels. From what you write, this seems to apply to Location: you may want to treat it as a...

2008/7/15 Simon Blomberg <s.blomberg1 at uq.edu.au>: > On Tue, 2008-07-15 at 13:43 +0800, Julie Marsh wrote: > >> >> >> Given that I am using 2 different tests for two different hypotheses I >> still would have expected...

On 27 April 2018 at 22:33, Nicolas Flaibani <n.flaiba at hotmail.com> wrote: > > Hi everyone! > > > I would like to join the discussion of the second topic (Specifying Multiple Random Effects in NLME by Dan) but in my case...

On 24 May 2018 at 21:22, Reinhold Kliegl <reinhold.kliegl at gmail.com> wrote: > Here is an update (final for now) with 10 models and 4 hierarchical > sequences. Comments, details, and a demonstration with the Machines data are > available...

Hi Luis I largely agree with Mike's answer and have the following additional comments: The decision of whether a variable is taken as fixed or random often rests on subject specific matter. An important question is: Can the levels...

There is no argument 'test' to anova.clm hence the error message. The likelihood ratio statistic (or, alternatively, G^2 statistic or Deviance statistic) has an asymptotic chi-square distribution, so it is the size of that statistic your reviewers...

Petri, I think you are confused about the use of orthogonal polynomials for ordered factors in model formulas rather than cumulative link models. If you first remove the ordering from the factors, I think you will find the output from...

Dear Charlie, I admit that I haven't read your email closely, but here is a way to test for non-proportional odds using the ordinal package (warning: self-promotion) using the wine data set also from the ordinal package...

Hi Emmanuel, You can use the clmm() function in package ordinal to fit cumulative link mixed models which include the proportional odds mixed model that you mention. The non-mixed equivalent, clm() gives the same answers as polr() and glm...

Malcolm, It happens that I have been doing some work tracking down that particular error message in the last couple of days, and I believe I have found a solution, at least for the most common link functions. I have...

Dear Vito No, you are not wrong, but you should center score prior to model estimation: summary(fm1 <- polr(factor(grade)~I(score - mean(score)))) which gives the same standard errors as do lrm. Now the intercepts refer the median...

Hi Richard You are trying to compare two models, that are not nested. This means that all usual asymptotics of the test statistics break down, hence the (second) test you are attempting is not meaningful. Usually one decides on the...

On 02/04/2008, John Maindonald <john.maindonald at anu.edu.au> wrote: > There was a related question from Mariana Martinez a day or two ago. > Before removing a random term that background knowledge or past > experience with similar data...

Hi Vito (question to the authors of MASS below) 2008/6/30 vito muggeo <vmuggeo at dssm.unipa.it>: > Dear Haubo, > many thanks for your reply. > Yes you are right, by scaling the "score", I get the same results. > > However...

Dear Aline, You are not alone in being surprised of the absence of residuals; I meet that question on a regular basis. And I would be delighted to implement residuals for CLMs and CLMMs in ordinal, its only that I...

Cyrus, On 29 September 2011 18:26, Cyrus Shaoul <cyrus.shaoul at ualberta.ca> wrote: > Hi All, > > I seem to have solved my own problem. I had been using a log transform. When > I removed the log transform, the distribution...

On 27 May 2011 17:03, Thomas Mang <thomasmang.ng at googlemail.com> wrote: > Hi, > > Consider the need for a mixed-effects model with an ordered multinomial > response variable. To the best of my knowledge, lme4 would not provide such...

Dear Sverre, You seem to be using clmm as it was intended to be used and my best guess is that the problems you observe are related to data structure and model identifiability. I have a few ideas that might...

Could you share the results of sessionInfo() and str(alllev)? Also please share the exact in- and output with relevant error messages; for example 'cntnew:male' does not make much sense without context. Unfortunately I don't understand your model...

On 22 March 2018 at 10:05, Maarten Jung <Maarten.Jung at mailbox.tu-dresden.de> wrote: > I think the problem is that there is only one observation per > subject-occasion-combination in this example. > In this case the random...