Table 2.

AIC goodness-of-fit measures for the two models (with or without random distance slopes) for the two dependent variables)

Formula	AIC
size ∼ distance + headset + distance * headset + (1 | participant)	11808
size ∼ distance + headset + distance * headset + (1 + distance | participant)	10591
depth ∼ distance + headset + distance * headset + (1 | participant)	17178
depth ∼ distance + headset + distance * headset + (1 + distance | participant)	16994

In both cases, the model with random slopes gave a better fit, as indicated by the lower AIC values