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means , CIs from lmer, glmer

On 27 February 2018 at 15:27, Kornbrot, Diana <d.e.kornbrot at herts.ac.uk>
wrote:
No, not always, but usually. In 'regular' cases (designed experiment with
the same denominator) the anova F-test is superior to the asymptotic
chi-square tests in the 'right' model.
I don't think it does:

library(lme4)
gm1 <- glmer(cbind(incidence, size - incidence) ~ period + (1 | herd),
             cbpp, binomial)
anova(gm1, gm2 <- update(gm1a, ~.-period))

Data: cbpp
Models:
gm2 <- update(gm1a, ~. - period): cbind(incidence, size - incidence) ~ (1 |
herd)
gm1: cbind(incidence, size - incidence) ~ period + (1 | herd)
                                 Df    AIC    BIC   logLik deviance Chisq
Chi Df
gm2 <- update(gm1a, ~. - period)  2 213.66 217.71 -104.832   209.66

gm1                               5 194.05 204.18  -92.027   184.05 25.61
    3
                                 Pr(>Chisq)
gm2 <- update(gm1a, ~. - period)
gm1                               1.151e-05 ***
---
Signif. codes:  0 ?***? 0.001 ?**? 0.01 ?*? 0.05 ?.? 0.1 ? ? 1

[actually, and to my surprise, anova(gm1) prints something that looks like
an anova table with a column labeled 'F', but I don't know what that means
(if it has a meaning). Wiser heads than mine will have to chip in here...]
Just printing the object (e.g. gm1) does give you the standard deviations
for the random effects. The mean is zero per definition, but I suspect that
this is not what you are really asking for?
I personally think that is an odd thing to ask for and I have no clue how
it is reasonably defined. I suspect you may have to use SPSS. I don't
really know what SPSS is doing but if it is doing a PQL-kind of thing that
would explain why you are led in the direction of F-tests (but note that
PQL is much inferior to the Laplace and AGQ methods in glmer).

Best
Rune

  
  
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