reply the post within 50 words:Here I am taking positive demand correlation as an example: Positively correlated products could be mutually complementary for the same users on different purposes, such as lids with cups, forks with knives, diapers with baby formulas, toilet paper with tissue with Kirkland water at Costco (this might be different reason compared to the above two - since you have already pushed your cart through the crowd to the back anyway)... Positively related at different store locations could be products serve a specific situation for all, such as: umbrellas, popsicles As a store manager, I would prefer negatively correlated product to avoid drowning in the safety stocks. I would hope the volatility from different SKUs would cancel out the overall variation, not only for the store inventory level but also for the total sales which my KPI might be based on