Chapter 9.2, Problem 8Q

A major source of “mercury poisoning” comes from the ingestion of methylmercury $\left({\text{CH}}_{\text{3}}{\text{Hg}}^{\text{+}}\right)$, which is found in contaminated fish (recall Question 5.3.3). Among the questions pursued by medical investigators trying to understand the nature of this particular health problem is whether methylmercury is equally hazardous to men and women. The following (121) are the halflives of methylmercury in the systems of six women and nine men who volunteered for a study where each subject was given an oral administration of ${\text{CH}}_{\text{3}}{\text{Hg}}^{\text{+}}$. Is there evidence here that women metabolize methylmercury at a different rate than men do? Do an appropriate two-sample t test at the $\alpha =0.01$ level of significance. The two sample standard deviations for these data are $s_X=15.1$ and $s_Y=8.1$.

Methylmercury $\left({\text{CH}}_3{\text{Hg}}^{\text{+}}\right)$ Females, $x_i$	Half-Lives (in days) Males, $y_i$
52	72
69	88
73	87
88	74
87	78
56	70
	78
	93
	74