Consider the study design and summary data presented in Exercise 12.2.4 to examine the correlation between age and the number of neurons in the CA1 region of the hippocampus.
(a) Can this study be used to gather evidence that aging is a cause for CA1 neuron loss? If not, what could be said? Briefly explain.
(b) Suppose the researchers had hypothesized that the number of neurons in the CA1 region increased with age and thus considered the directional test of HA: p > 0. Considering all of the information above, what would be the resulting P-value and conclusions for this test?