21 Answers to some labs exercises

Answers in Sect. 6.14.

Answer to Exercise 6.1: 1. $H_0$: $\mu =7725$; $H_1$: $\mu \ne 7725$ (two tailed). 2. $\overline{x}=6753.64$ and $\text{s.e.}\left(\overline{x}\right)=s/\sqrt{n}=1142.123/\sqrt{11}=344.363$. 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).