Two Types of Fish Attractors, One Made from Vitrified Clay $\quad$

Two types of fish attractors, one made from vitrified clay pipes and the other from cement blocks and brush, were used during 16 different time periods spanning 4 years at Lake Tohopekaliga, Florida The following observations are of fish caught per fishing day. $\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\text { Period }$
$\begin{array}{l|cccccccc} \hline& \mathbf{1} & \mathbf{2} & \mathbf{3} & \mathbf{4} & \mathbf{5} & \mathbf{6} & \mathbf{7} & \mathbf{8} \\\hline \text { Pipe } & .00 & 1.80 & 4.86 & .58 & .37 & .32 & .11 & .23 \\\text { Brush } & .48 & 2.33 & 5.38 & .79 & 32 & .76 & .52 & .91 \\\hline\end{array}$



$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\text { Period }$
$\begin{array}{l|cccccccc} \hline& \mathbf{9} & \mathbf{1 0} & \mathbf{1 1} & \mathbf{1 2} & \mathbf{1 3} & \mathbf{1 4} & \mathbf{1 5} & \mathbf{1 6} \\\hline \text { Pipe } & .29 & .85 & 6.64 & .57 & 1.83 & 7.89 & .63 & .42 \\\text { Brush } & .75 & 1.61 & 9.73 & .83 & 2.17 & \mathbf{8 . 2 1} & .56 & .75 \\\hline\end{array}$


Does one attractor appear to be more effective on average than the other?
a. Use the paired t test with $\alpha = .01 \text { to test } H _ { 0 } : \mu _ { D } = 0 \text { versus } H _ { 0 } : \mu _ { D } \neq 0$

b. What happens if the two-sample t test is used $\left( s _ { 1 } = 2.48 \text { and } s _ { 2 } = 2.91 \right) ?$