A vendor of a software product claims that their new program/app for helping student self-study mathematics greatly enhances the understanding of key mathematical concepts among school students. They approached the Prince County School District with the suggestion that the program be adopted in county schools and integrated into the curriculum. While the program?which runs on PC/Mac/iPad?has a very nice user interface, it is expensive. The county wants to know what the effect of adopting this program will be on student outcomes. They are aware that some students are already using the program (on personal licenses) and collect data from three schools. The data is described in the following table:

Variable	Description
Score (Dependent Variable)	Aggregate score on math exams over the last year (out of 400)
Income	Family income in dollars
Use	Whether software has been used for at least 12 months (1 if yes and 0 if no)
School	School attended (identified as A, B, or C)
Age	Student age (in years)

The categorical variable School, is recoded using two dummy variables: School_A = 1 if School = A, and 0 otherwise;

School_B = 1 if School = B, and 0 otherwise.

The regression output is given below: