str(cake)
## 'temp' is continuous, 'temperature' an ordered factor with 6 levels
fm1 <- lmer(angle ~ recipe * temperature + (1|recipe:replicate), cake, REML= FALSE)
print(fm1, corr=FALSE)
fm2 <- lmer(angle ~ recipe + temperature + (1|recipe:replicate), cake, REML= FALSE)
print(fm2, corr=FALSE)
fm3 <- lmer(angle ~ recipe + temp + (1|recipe:replicate), cake, REML= FALSE)
fm3
## and now "choose" :
anova(fm3, fm2, fm1)
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