$$\begin{array}{l}
\text { Data sets } \mathrm { A } \text { and } \mathrm { B } \text { are dependent. Find } \overline { \mathrm { d } } \text {. }\
\begin{array} { c | c c c c c }
\mathrm { A } & 6.1 & 7.1 & 9.0 & 6.0 & 6.1 \
\hline \mathrm { B } & 8.5 & 7.4 & 7.3 & 7.2 & 8.6
\end{array}
\end{array}$$ Assume that the paired data came from a population that is normally distributed.
A) -0.94
B) -0.76
C) 0.58
D) 0.89

Question

$$\begin{array}{l}
\text { Data sets } \mathrm { A } \text { and } \mathrm { B } \text { are dependent. Find } \overline { \mathrm { d } } \text {. }\
\begin{array} { c | c c c c c } 
\mathrm { A } & 6.1 & 7.1 & 9.0 & 6.0 & 6.1 \
\hline \mathrm { B } & 8.5 & 7.4 & 7.3 & 7.2 & 8.6
\end{array}
\end{array}$$ Assume that the paired data came from a population that is normally distributed.
A) -0.94
B) -0.76
C) 0.58
D) 0.89

Quizplus · Accepted Answer

To find $\overline{d}$, the mean difference between the dependent data sets A and B, you subtract each value in B from its corresponding value in A and then find the mean of these differences. $$d_i = A_i - B_i$$$$d = (6.1-8.5), (7.1-7.4), (9.0-7.3), (6.0-7.2), (6.1-8.6)$$$$d = -2.4, -0.3, 1.7, -1.2, -2.5$$$$\overline{d} = \frac{-2.4 - 0.3 + 1.7 - 1.2 - 2.5}{5}$$$$\overline{d} = \frac{-4.7}{5} = -0.94$$Thus, the mean difference $\overline{d}$ is -0.94.

Assume That the Paired Data Came from a Population That