I am trying to run a multiple regression test in JMP, but my residual data did not meet the distribution assumption. Skewness was -1.21, and kurtosis was 4.52, so my data is negatively skewed. How do I proceed? (I'm somewhat of a newbie.) We haven't learned about transformations such as log or square root. I tried both of these by adding them separately as formulas for the residual data column, but all I got was unworkable dots in the column.