I am considering an ANOVA model for such data:
Student Class Points on exam Day of studying 1 P1 12 Day 10 2 P3 23 Day 5 3 P3 8 Day 1 4 P2 36 Day 10 5 P1 10 Day 1 6 P2 86 Day 10 7 P1 13 Day 5 ...
and such ANOVA model:
model <- aov(Points ~ Class + Day, data) ggqqplot(residuals(model))
how can I check if this model satisfies the normality of distribution? (other than the Q-Q plot of the model?)
My Q-Q plot of the model (above) seems to show normal distribution but when I perform Shapiro-Wilk( that considers only Points) the p-value comes out incredibly small... Therefore I don't know if I can assume the normality or not.
Shapiro-Wilk normality test data: Points W = 0.92212, p-value = 9.97e-13