I'm working on a dataset which isn't normally distributed. The dataset contains three dimensions like cost, discount and profit.
I'm trying to find possible outliers in all these dimensions. I used Z-score to detect outliers in single dimension to find which high cost is causing outliers.
As a next step I tried to find outliers with high cost and high profit and low discount.
I came up with a formula of :
Zscore(cost) + Zscore(profit) - Zscore(discount)
negative sign because I want to find outliers with low discount.
Is this approach meaningful to do? or is there any further proven way to achieve this?