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Message-ID: <dd92a18a-92d0-49c4-f37c-c185b97af299@gmail.com>
Date: 2019-05-03T02:53:24Z
From: Ben Bolker
Subject: What p value should I report here?
In-Reply-To: <CAGP99JHO51FpxRDDbH+d1tpg65YBdzPZtXc8eH7NuzM40spE8w@mail.gmail.com>

What we'd like to see is the *results* of summary(Vert_effect) and
summary(model.frame(glmm_Vert_effect)) ... for example, if I was running
the first example in ?lmer, the desired output would look something like
this (here, the two outputs are identical because there are no NA values
in the input).


> library(lme4)
Loading required package: Matrix
> fm1 <- lmer(Reaction~Days+(1|Subject), sleepstudy)
> summary(sleepstudy)
    Reaction          Days        Subject
 Min.   :194.3   Min.   :0.0   308    : 10
 1st Qu.:255.4   1st Qu.:2.0   309    : 10
 Median :288.7   Median :4.5   310    : 10
 Mean   :298.5   Mean   :4.5   330    : 10
 3rd Qu.:336.8   3rd Qu.:7.0   331    : 10
 Max.   :466.4   Max.   :9.0   332    : 10
                               (Other):120
> summary(model.frame(fm1))
    Reaction          Days        Subject
 Min.   :194.3   Min.   :0.0   308    : 10
 1st Qu.:255.4   1st Qu.:2.0   309    : 10
 Median :288.7   Median :4.5   310    : 10
 Mean   :298.5   Mean   :4.5   330    : 10
 3rd Qu.:336.8   3rd Qu.:7.0   331    : 10
 Max.   :466.4   Max.   :9.0   332    : 10
                               (Other):120


On 2019-05-02 10:51 p.m., DESPINA MICHAILIDOU wrote:
> The code is
> 
> glmm_Vert_effect?<- glmer(Vert_effect?~ P-Diz-today?+ (1|
> ID/SCAN_DATE/Side), data=GCA_data, family=binomial(link= "logit"))
> 
> summary(Vert_effect).
> 
> 
> That is your question?
> 
> 
> I am sorry i am very new to R.
> 
> 
> Thank you for your interest and help. Really appreciate it.
> 
> 
> Despina
> 
> 
> ???? ???, 2 ??? 2019 ???? 10:40 ?.?., ?/? Ben Bolker <bbolker at gmail.com
> <mailto:bbolker at gmail.com>> ??????:
> 
> 
>     ? We will be able to help much better if you can provide a reproducible
>     example, or at least the results of the summary() commands requested
>     below ...
> 
>     On 2019-05-02 10:29 p.m., DESPINA MICHAILIDOU wrote:
>     > Yes you are correct. I have a 0 or 1 scoring outcome. I do have some
>     > blanks in my observations.? Thank you for your response.
>     >
>     > Despina
>     >
>     > ???? ???, 2 ??? 2019 ???? 10:19 ?.?., ?/? Ben Bolker
>     <bbolker at gmail.com <mailto:bbolker at gmail.com>
>     > <mailto:bbolker at gmail.com <mailto:bbolker at gmail.com>>> ??????:
>     >
>     >
>     >? ? ?? Can you show us summary(GCA_data) and
>     >? ? ?summary(model.frame(fitted_model)) please? It looks like for
>     some reason
>     >? ? ?(maybe because of observations dropped due to NA values?) you
>     have no
>     >? ? ?variation in your predictor variable (P_Diz_today).
>     >
>     >? ? ?? It's also potentially problematic that you have an
>     observation-level
>     >? ? ?random effect for a Bernoulli outcome (i.e., you're fitting a
>     binomial
>     >? ? ?model with a single-column value as the response and no weights=
>     >? ? ?argument, which implies you have a 0/1 outcome; you have the
>     same number
>     >? ? ?of groups in your fully nested [ID:Scan:Side] random effect as
>     >? ? ?observations), but I don't think this would lead to the
>     dropping of the
>     >? ? ?P_Diz_today predictor ...
>     >
>     >? ? ?? cheers
>     >? ? ?? ? Ben Bolker
>     >
>     >? ? ?On 2019-05-02 3:30 p.m., DESPINA MICHAILIDOU wrote:
>     >? ? ?> Hi everyone,
>     >? ? ?>
>     >? ? ?>
>     >? ? ?> I am running this regression analysis model and I get the
>     >? ? ?following output.
>     >? ? ?> What P value should I report for my variable P-Dizz today?What
>     >? ? ?does it mean
>     >? ? ?> that fixed-effect model matrix is rank deficient so dropping 1
>     >? ? ?column /
>     >? ? ?> coefficient? Can anyone help me with the interpretation of
>     those data?
>     >? ? ?>
>     >? ? ?>
>     >? ? ?> Thank you in advance.
>     >? ? ?>
>     >? ? ?>
>     >? ? ?> Despina
>     >? ? ?>
>     >? ? ?>
>     >? ? ?> Generalized linear mixed model fit by maximum likelihood
>     (Laplace
>     >? ? ?> Approximation) ['glmerMod']
>     >? ? ?>
>     >? ? ?>? Family: binomial? ( logit )
>     >? ? ?>
>     >? ? ?> Formula: Vert_effect ~ P_Diz_today + (1 | ID/SCAN_DATE/Side)
>     >? ? ?>
>     >? ? ?>? ? Data: GCA_data
>     >? ? ?>
>     >? ? ?>
>     >? ? ?>
>     >? ? ?>? ? ? AIC? ? ? BIC? ?logLik deviance df.resid
>     >? ? ?>
>     >? ? ?>? ? ?80.3? ? ?94.5? ? -36.1? ? ?72.3? ? ? 254
>     >? ? ?>
>     >? ? ?>
>     >? ? ?>
>     >? ? ?> Scaled residuals:
>     >? ? ?>
>     >? ? ?>? ? ? ?Min? ? ? ? 1Q? ? Median? ? ? ? 3Q? ? ? ?Max
>     >? ? ?>
>     >? ? ?> -0.012501 -0.000639 -0.000639 -0.000639? 0.105723
>     >? ? ?>
>     >? ? ?>
>     >? ? ?>
>     >? ? ?> Random effects:
>     >? ? ?>
>     >? ? ?>? Groups? ? ? ? ? ? ? Name? ? ? ? Variance Std.Dev.
>     >? ? ?>
>     >? ? ?>? Side:(SCAN_DATE:ID) (Intercept) 1502.7? ?38.76
>     >? ? ?>
>     >? ? ?>? SCAN_DATE:ID? ? ? ? (Intercept)? ? 0.0? ? 0.00
>     >? ? ?>
>     >? ? ?>? ID? ? ? ? ? ? ? ? ? (Intercept)? 235.1? ?15.33
>     >? ? ?>
>     >? ? ?> Number of obs: 258, groups:? Side:(SCAN_DATE:ID), 258;
>     >? ? ?SCAN_DATE:ID, 130;
>     >? ? ?> ID, 52
>     >? ? ?>
>     >? ? ?>
>     >? ? ?>
>     >? ? ?> Fixed effects:
>     >? ? ?>
>     >? ? ?>? ? ? ? ? ? ?Estimate Std. Error z value Pr(>|z|)
>     >? ? ?>
>     >? ? ?> (Intercept)? -14.711? ? ? 3.646? -4.035 5.47e-05 ***
>     >? ? ?>
>     >? ? ?> ---
>     >? ? ?>
>     >? ? ?> Signif. codes:? 0 ?***? 0.001 ?**? 0.01 ?*? 0.05 ?.? 0.1 ? ? 1
>     >? ? ?>
>     >? ? ?> fit warnings:
>     >? ? ?>
>     >? ? ?> fixed-effect model matrix is rank deficient so dropping 1
>     column /
>     >? ? ?> coefficient
>     >? ? ?>
>     >? ? ?> convergence code: 0
>     >? ? ?>
>     >? ? ?> boundary (singular) fit: see ?isSingular
>     >? ? ?>
>     >? ? ?>? ? ? ?[[alternative HTML version deleted]]
>     >? ? ?>
>     >? ? ?> _______________________________________________
>     >? ? ?> R-sig-mixed-models at r-project.org
>     <mailto:R-sig-mixed-models at r-project.org>
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>     >? ? ?>
>     >
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