Suppose 12 halfbacks are observed during spring training, six sampled from the freshmen and sophomores and six from the juniors and seniors. Each is given the opportunity of running four plays against...

Suppose 12 halfbacks are observed during spring training, six

sampled from the freshmen and sophomores and six from the juniors

and seniors. Each is given the opportunity of running four plays

against the best defensive team.. The resulting total yards for

players is given below:

(a) Use N2SAMP to test the hypothesis that freshmen and sophomore

backs are equally as good as junior and senior backs against

the alternative that junior and senior backs are better.

Use a = 0.05.

(b) Find a 95% confidence interval for µ2 - µ1 •