I am a student in M1 in experimental economics. I am struggling with a glmer model because I don’t know if the R function clusters the standard errors and if including a random intercept already had a similar effect (of clustering the standard errors). More precisely, I introduced a random intercept for controlling the intra-individual variability in my participants decisions (they take 18 decisions), but I am afraid to finish with biased results. In fact, I see that my residuals are not normally distributed (see below) and I am hoping it’s just because of this …