Artificial hip joints consist of a ball and socket. As the joint wears, the ball (head) becomes rough. Investigators performed wear tests on metal artificial; hip joints. Joints with several different diameters were tested. The following table presents measurements of head roughness (in nanometers).
$\begin{array}{ccccc}
\hline \text { Diameter } & {\text { Head Roughness }} \
\hline 16 & 27.5 & 21.4 & 27.4 & 26.3 \
24 & 30.2 & 35.6 & 33.8 & \
30 & 24.9 & 21.2 & 25.5 & \
\hline
\end{array}$
Can you conclude that the mean roughness varies with diameter? Use the $\alpha = 0.01$ level o significance.

Question

Quizplus · Accepted Answer

Since the P-value is less than $\alpha = 0.01$, we reject the null hypothesis and conclude that the mean roughness varies with diameter.

Artificial Hip Joints Consist of a Ball and Socket Can You Conclude That the Mean Roughness Varies with Diameter