Linked Questions

21
votes
0answers
13k views

Formula symbols for mixed model using lme4 [duplicate]

I often confuse symbols :, |, / and * in the ...
7
votes
1answer
4k views

Understanding the random effect in linear mixed models (lme4, R) [duplicate]

I am familiar with linear regression models but the random section of linear mixed models just melts my mind. I did find an excellent guide that could have helped me but the languageR package is not ...
6
votes
0answers
765 views

simple repeated measures syntax - lme vs. lmer [duplicate]

I'm trying to look for significant effects on "similarity" (of "isinpair" and controlling for time effects) using repeated measures with an in group sample. The intervention "isinpair" occurs after a ...
6
votes
0answers
127 views

Autocorrelation specification in lme ) [duplicate]

I am modeling wood properties variation of several individual within the same tree species using multilevel lme(). I specified a first model as : ...
1
vote
0answers
154 views

r lmer syntax for mixed model ANOVA [duplicate]

I have a question concerning a mixed model ANOVA conducted using the lmer function of the lme4 package. Despite a lengthy research across tutorials and forum entries I do not have a clear response to ...
0
votes
0answers
124 views

Formula for lmer() [duplicate]

How does the formula for the lmer function work? Some examples: ...
26
votes
2answers
18k views

Have I correctly specified my model in lmer?

I have scoured lots of help sites and am still confused about how to specify more complicated nested terms in a mixed model as well. I am also confused as the use of ...
19
votes
3answers
4k views

Interpreting three forms of a “mixed model”

There's a distinction that's tripping me up with mixed models, and I'm wondering if I could get some clarity on it. Let's assume you've got a mixed model of count data. There's a variable you know you ...
19
votes
2answers
29k views

Repeated measures ANOVA with lme/lmer in R for two within-subject factors

I'm trying to use lme from the nlme package to replicate results from aov for repeated ...
27
votes
2answers
2k views

In a multi-level model, what are the practical implications of estimating versus not-estimating random effect correlation parameters?

In a multi-level model, what are the practical and interpretation-related implications of estimating versus not-estimating random effect correlation parameters? The practical reason for asking this ...
8
votes
1answer
8k views

How to account for repeated measures in glmer?

My design is as follows. $y$ is Bernoulli response $x_1$ is a continuous variable $x_2$ is a categorical (factor) variable with two levels The experiment is completely within subjects. That is, ...
5
votes
4answers
6k views

What regression analysis should I perform on my data and why?

I am a law student researching which factors influence the CSR (corporate social responsibility, GSE_RAW) behavior of companies. As my studies didn't offer any ...
0
votes
1answer
7k views

Number of random effects is not correct in lmer model

I am getting this error. ...
7
votes
0answers
20k views

Error Message in lme() :Error in MEEM(object, conLin, control$niterEM) : Singularity in backsolve at level 0, block 1 [closed]

I have a dataframe called "cleaned", which consists of about 300,000 rows and 13 variables. Except the dependent variable, all variables are categorical and have multiple levels ($\geq2$). The ...
13
votes
1answer
579 views

Equivalence of (0 + factor|group) and (1|group) + (1|group:factor) random effect specifications in case of compound symmetry

Douglas Bates states that the following models are equivalent "if the variance-covariance matrix for the vector-valued random effects has a special form, called compound symmetry" (slide 91 in this ...

15 30 50 per page