# isREML: Check characteristics of models In lme4: Linear Mixed-Effects Models using 'Eigen' and S4

## Description

Check characteristics of models: whether a model fit corresponds to a linear (LMM), generalized linear (GLMM), or nonlinear (NLMM) mixed model, and whether a linear mixed model has been fitted by REML or not (`isREML(x)` is always `FALSE` for GLMMs and NLMMs).

## Usage

 ```1 2 3 4 5 6 7``` ``` isREML(x, ...) isLMM(x, ...) isNLMM(x, ...) isGLMM(x, ...) ```

## Arguments

 `x` a fitted model. `...` additional, optional arguments. (None are used in the merMod methods)

## Details

These are generic functions. At present the only methods are for mixed-effects models of class `merMod`.

a logical value

getME

## Examples

 ``` 1 2 3 4 5 6 7 8 9 10 11 12``` ```fm1 <- lmer(Reaction ~ Days + (Days|Subject), sleepstudy) gm1 <- glmer(cbind(incidence, size - incidence) ~ period + (1 | herd), data = cbpp, family = binomial) nm1 <- nlmer(circumference ~ SSlogis(age, Asym, xmid, scal) ~ Asym|Tree, Orange, start = c(Asym = 200, xmid = 725, scal = 350)) isLMM(fm1) isGLMM(gm1) ## check all : is.MM <- function(x) c(LMM = isLMM(x), GLMM= isGLMM(x), NLMM= isNLMM(x)) stopifnot(cbind(is.MM(fm1), is.MM(gm1), is.MM(nm1)) == diag(rep(TRUE,3))) ```

### Example output

```Loading required package: Matrix
[1] TRUE
[1] TRUE
```

lme4 documentation built on June 22, 2021, 9:07 a.m.