1. The file store.xls contains sales data for a given product from many months in a store, as well as the number of feet of shelf space devoted to the product, the retail price, advertising expenditures and whether or not a coupon was available that month. What impact on sales does the coupon seem to have?

https://docs.google.com/spreadsheets/d/1uSH8lKX7kXA_lE0HM3-APoU2pmTQXn7DpgeCVp02luc/edit?usp=sharing

*google doc is for reference of the retention.xls file. You will need to run a regression analysis