Displaying 9 results from an estimated 9 matches similar to: "lme4/lmer: P-Values from mcmc samples or chi2-tests?"
2007 Feb 12
1
lmer and estimation of p-values: error with mcmcpvalue()
Dear all,
I am currently analyzing count data from a hierarchical design, and I?ve
tried to follow the suggestions for a correct estimation of p-values as
discusssed at R-Wiki
(http://wiki.r-project.org/rwiki/doku.php?id=guides:lmer-tests&s=lme%20and%20aov).
However, I have the problem that my model only consists of parameters
with just 1 d.f. (intercepts, slopes), so that the
2007 Mar 12
0
Pvalues and lme
Dear R users,
I have developed a model
I have compared several options of obtaining p-values for
poisson lmer model including Marlov chain monty carlo methods, single
term deletions and summary.
>
> However, I encountered several problems that can be classified as
> (1) the p values from the summary command are total different from
those derived from Marlov chain monty carlo methods
>
2009 Feb 24
2
lmer, estimation of p-values and mcmcsamp
(To the list moderator: I just subscribed to the list. Apologies for not
having done so longer before trying to post.)
Hi all,
I am currently using lmer to analyze data from an experiment with a
single fixed factor (treatment, 6 levels) and a single random factor
(block). I've been trying to follow the online guidance for estimating
p-values for parameter estimates on these and other
2010 Nov 09
2
new column from column in another df
If I have a data frame where a species occupies several rows with different
phases such as (both col's ar factors):
species,phase
Populus tremula,1
Populus tremula,2
Populus tremula,3
Calluna vulgaris,1
Calluna vulgaris,2
Betula alba,1
Betula alba,2
Betula alba,3
Primula veris,1
Primula veris,2
and another df where each species only have one row:
species,growth_form
Populus tremula,tree
Acer
2005 Sep 12
0
Multiple comparisons like a Chi2 or Fisher's exact test
Dear all
I have an experiment where plots either have or have not regrown (in 40
plots) after receiving 12 different herbicide treatments and a control (no
treatment). The data are significant with a Chi2, but to later distinguish
if the differences are significant between each of the 12 treatments apart I
need to do multiple Chi2 s between each. Is there a way to run those
multiple Chi2 or
2007 Mar 12
2
Lmer Mcmc Summary and p values
Dear R users
I am trying to obtain p-values for (quasi)poisson lmer models, including
Markov-chain Monte Carlo sampling and the command summary.
>
> My problems is that p values derived from both these methods are
totally different. My question is
(1) there a bug in my code and
>
(2) How can I proceed, left with these uncertainties in the estimations of
> the p-values?
>
> Below
2007 Oct 10
5
chi2
Hello,
I want to use the quantile function so I read the doc but I don't understand with this
> qchisq(seq(0.05,0.95,by=0.05),df=(length(don)-1))
[1] 62667.11 62795.62 62882.42 62951.47 63010.74 63064.00 63113.39 63160.27 63205.65 63250.33 63295.04 63340.48 63387.48 63437.03 63490.53 63550.14 63619.68
[18] 63707.24 63837.16
Can you help me please?
2007 Mar 13
1
lme4 and mcmcamp
Dear R users
I am trying to obtain p-values for (quasi)poisson lmer models, using
Markov-chain Monte Carlo sampling and the command summary.
>
> My problems is that p values derived from both these methods are
totally different. My question is
(1) there a bug in my code and
>
(2) How can I proceed, left with these uncertainties in the estimations of
> the p-values?
>
> Below is
2008 Aug 29
1
significance of random effects in poisson lmer
Hi,
I am having problems trying to assess the significance of random terms
in a generalized linear mixed model using lme4 package. The model
describes bird species richness R along roads (offset by log length of
road log_length) as a function of fixed effects Shrub (%shrub cover) and
Width (width of road), and random effect Site (nested within Site
Cluster).
>From reading answers to previous