Linked Questions

1
vote
0answers
287 views

Using REML in mixed models if random factor is small [duplicate]

I'm trying to fit linear mixed models to 3 different DV (so three models). I understand that REML gives less biased variance estimates. As im more interested in the fixed effects, I use ML for the ...
142
votes
15answers
117k views

Intuitive explanation for dividing by $n-1$ when calculating standard deviation?

I was asked today in class why you divide the sum of square error by $n-1$ instead of with $n$, when calculating the standard deviation. I said I am not going to answer it in class (since I didn't ...
94
votes
11answers
56k views

Maximum Likelihood Estimation (MLE) in layman terms

Could anyone explain to me in detail about maximum likelihood estimation (MLE) in layman's terms? I would like to know the underlying concept before going into mathematical derivation or equation.
74
votes
3answers
64k views

What is “restricted maximum likelihood” and when should it be used?

I have read in the abstract of this paper that: "The maximum likelihood (ML) procedure of Hartley aud Rao is modified by adapting a transformation from Patterson and Thompson which partitions the ...
18
votes
2answers
30k views

REML or ML to compare two mixed effects models with differing fixed effects, but with the same random effect?

Background: Note: My dataset and r-code are included below text I wish to use AIC to compare two mixed effects models generated using the lme4 package in R. Each model has one fixed effect and one ...
4
votes
5answers
5k views

Comparing the within-subject variance between two groups of subjects

If each subject has repeated a test multiple times, I am able to compute the mean and variance of their performance. (I am assuming the results to be normally distributed). 1) If it is the variance ...
6
votes
1answer
7k views

R mixed models: lme, lmer or both? which one is relevant for my data and why?

I have a data obtained through forest inventory conducted yearly (1994-2015) in a West African country. 10 plots of equal sizes (1 ha each) were selected from unmanaged natural forest and then ...
5
votes
2answers
2k views

When no model comparison, should I use REML vs ML?

I'm running LMM, and I will make no comparison of models. Could I ask which one should I use between REML and ML?
2
votes
1answer
3k views

R: default correlation in nlme::lme

I just noticed that the default correlation of nlme::lme() is NULL. The explanation of argument for correlation is correlation: ... Defaults to NULL, corresponding to no within-group ...
1
vote
2answers
505 views

Kenward-Roger and REML

I am doing some mixed model analyses using the lmer function in R's lme4 package. I am using the ...
1
vote
0answers
244 views

What is the difference between Restricted Maximum Likelihood (REML) and Maximum Likelihood (ML)? [duplicate]

I am a first year graduate student in biostatistics, and I have somewhat of an idea of the difference between REML and ML. However, I want a more in-depth understanding of each estimation method, ...