Please refer to the Anova and Simple Regression Projects.
Your company would like you to complete their sales prediction model. They would like you to ascertain if the other variables for which they have data also affect sales. A complete model will have to include advertising expenditures and package design along with the other variables listed above.
1. Create three dummy variables named DA, DB, and DC to capture the effects of the four levels of the categorical variable. Then use Tools > Data Analysis > Regression, to fit a regression of Sales as a function of all the variables in your data set (variables 3 through 7 above), plus the three dummies DA, DB, and DC.