# Statistics help

Instructor’s Notes:

Again, use the data sheet used so far to structure and test hypotheses. Students have been getting confused what problems to do.

1. There are two problems to solve—one for each major. Is the mean cost \$160K to within a 95% confidence? The problem says 5%–but means 95%–don’t be confused.

2. There is one problem to solve—compare the two majors. Test, to within a 90% confidence (the problem set says 10%, but means 90%), whether or not 30 year ROI is less for business managers than for engineering majors.

Using the ROI data set:

1. For each of the 2 majors test the hypothesis at the 5% significance level:
• The mean ‘Cost’ for a college is \$160,000. Be sure to interpret your results.
2. For Business versus Engineering majors conduct a two sample test of the hypothesis at the 10% significance level (assume the variances are not equal):
• The average ’30-Year ROI’ for Business majors is less than for Engineering Majors. Be sure to interpret your results.