Open Misch007 opened 3 years ago
Hi @Misch007, model-comparison objects of class anova
are indeed not supported. However, objects of class mixed
which are the output of mixed()
are supported. If you are only testing for single-term deletions you could use
apa_print(mixed(..., method = "LRT")
with the more-complex model specified in the formula to get the same result as from anova()
. This is only a workaround and I think we should support model-comparison objects of class anova
, soon.
Hey @mariusbarth!
Thanks a lot for the quick answer!
I am really sorry, but unfortunately I am not quite following... I did not manage to get the same result as from anova()
output with your advice. Would you mind giving an example, this is the data I tried it with:
participant<-c("vp1","vp2","vp3","vp4","vp5")
group<-c("intervention", "control","control","intervention","control")
df<-data.frame(participant,group) %>%
group_by(participant,group) %>%
summarise(session=c("t1","t2","t3","t4")) %>%
group_by(participant, group, session) %>%
summarise(task=c("a","b")) %>%
ungroup() %>%
mutate(errors=floor(runif(n=40,min=0,max=30)))
lmm1 <- mixed(errors~group*session*task+(1|participant), df)
lmm2 <- mixed(errors~group*task+(1|participant), df)
anova(lmm1,lmm2)
Data: data
Models:
lmm2: errors ~ group * task + (1 | participant)
lmm1: errors ~ group * session * task + (1 | participant)
npar AIC BIC logLik deviance Chisq Df Pr(>Chisq)
lmm2 6 289.79 299.93 -138.90 277.79
lmm1 18 256.47 286.87 -110.24 220.47 57.322 12 6.915e-08 ***
---
Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1
Best regards and once again: Thanks a lot! Mischa
Hi @Misch007, unfortunately, this is a case where the workaround won't work: You basically compare a model with two main effects and an interaction term with a more complex model with one three-way interaction, three two-way interactions, and three main effects, so it's not the single-term deletion case. For cases as such, we would really need a method for anova
objects.
Ah, got it! Thanks for the explanation and good luck on this one!
Hey!
I hope I am not missing something! As far as I understood (#27) model comparisons are only supported for
lm
objects? I am comparing linear mixed models created by the functionafex::mixed()
viaanova()
. I'd like to report them using apa_print(). What do you think about this support?Best regards and thanks for the great work! Mischa