A Researcher Is Conducting a Matched-Pairs Study Assume That the Data Are Normally Distributed in the Population

Multiple Choice

A researcher is conducting a matched-pairs study.She gathers data on each pair in the study resulting in: $$\begin{array} { | c | c | c | } \hline \text { Pair } & \text { Group 1 } & \text { Group } 2 \\\hline 1 & 10 & 12 \\\hline 2 & 8 & 9 \\\hline 3 & 11 & 11 \\\hline 4 & 8 & 10 \\\hline 5 & 9 & 12 \\\hline\end{array}$$ Assume that the data are normally distributed in the population.The sample standard deviation (s_d) of the differences is _______.

A) 1.30
B) 1.14
C) 1.04
D) 1.02
E) 1.47