21 Answers to some labs exercises

Answers in Sect. 6.14.

Answer to Exercise 6.1: 1. \(H_0\): \(\mu=7725\); \(H_1\): \(\mu\ne7725\) (two tailed). 2. \(\bar{x} = 6753.64\) and \(\text{s.e.}(\bar{x}) = s/\sqrt{n} = 1142.123/\sqrt{11} = 344.363\). 3. \(t = (6753.64 - 7725)/344.363 = -2.821\), as in output. This ‘large’; expect small \(P\)-value; software confirms this: two-tailed \(P=0.018\). 4. Moderate evidence (\(P = 0.018\)) that the mean energy intake is not meeting the recommended daily energy intake (mean: 6753.6kJ; std. dev.: 1142.1kJ).