You are employed by a firm that has a contract to examine educational scores from school districts throughout the state. Your job is to report to the state legislature on whether thos districts have met their legislatively mandated goals. Your state contains districts with large cultural, economic, and familial differences, and those legislative goals are related both to improving test scores over time for all schools, and for lessening the range of those scores.
a) When comparing your district average to the state average, what is the appropriate TEST of the hypothesis that your district has higher average scores than the state average?
b) When comparing your district to another district, what TEST would you use?
c) When comparing your district this year to your district last year, what TEST would you use?