A multiple-comparison procedure for comparing four treatment means produced the confidence intervals shown below. Rank the means from smallest to largest. Use solid lines to connect those means which are not significantly different. $$\begin{array} { l }
\left( \mu _ { 1 } - \mu _ { 2 } \right) : ( 8,20 ) \
\left( \mu _ { 1 } - \mu _ { 3 } \right) : ( - 8,4 ) \
\left( \mu _ { 1 } - \mu _ { 4 } \right) : ( 8,22 ) \
\left( \mu _ { 2 } - \mu _ { 3 } \right) : ( - 22 , - 10 ) \
\left( \mu _ { 2 } - \mu _ { 4 } \right) : ( - 2,4 ) \
\left( \mu _ { 3 } - \mu _ { 4 } \right) : ( 13,21 )
\end{array}$$
A) $24 \overline { 13 }$
B) 4213
C) $\overline { 41 } \overline { 23 }$
D) $\overline { 42 } \overline { 13 }$

Question

A multiple-comparison procedure for comparing four treatment means produced the confidence intervals shown below. Rank the means from smallest to largest. Use solid lines to connect those means which are not significantly different. $$\begin{array} { l } 
\left( \mu _ { 1 } - \mu _ { 2 } \right) : ( 8,20 ) \
\left( \mu _ { 1 } - \mu _ { 3 } \right) : ( - 8,4 ) \
\left( \mu _ { 1 } - \mu _ { 4 } \right) : ( 8,22 ) \
\left( \mu _ { 2 } - \mu _ { 3 } \right) : ( - 22 , - 10 ) \
\left( \mu _ { 2 } - \mu _ { 4 } \right) : ( - 2,4 ) \
\left( \mu _ { 3 } - \mu _ { 4 } \right) : ( 13,21 )
\end{array}$$
A) $24 \overline { 13 }$
B) 4213
C) $\overline { 41 } \overline { 23 }$
D) $\overline { 42 } \overline { 13 }$

Quizplus · Accepted Answer

The confidence intervals indicate that $\mu_1$ and $\mu_3$ are not significantly different, and $\mu_2$ and $\mu_4$ are not significantly different. The ranking from smallest to largest is $\mu_4$, $\mu_2$, $\mu_1$, $\mu_3$, with $\mu_4$ and $\mu_2$ connected, and $\mu_1$ and $\mu_3$ connected.

A Multiple-Comparison Procedure for Comparing Four Treatment Means Produced the Confidence