Am I allowed to use multiple regression analysis on a sample size of 21? I did the Shapiro - Wilik test on all four of my variables (p>0,05 on all of them). I also checked their linear distribuon and possible outliers in the screeplots, and everything seems fine. So my question is can i use the multiple regression analysis even though my sample size is less than 30, but the conditions of normality and linear relationships are satisfied?
Thank you in advance!