Chapter 10.2, Problem 20E

Suppose that you arc an inspector for the Fish and Game Department and that you are given the task of determining whether to prohibit fishing along part of the Oregon coast. You will close an area to fishing if it is determined that fish in that region have an unacceptably high mercury content.

1. a. Assuming that a mercury concentration of 5 ppm is considered the maximum safe concentration, which of the following pairs of hypotheses would you test:

   $H_0:\mu =\text{5}\text{versus}{H}_a: \mu >\text{5}$

or

$H_0:\mu =\text{5 }\text{versus}{H}_a:\mu <\text{5}$

Give the reasons for your choice.

1. b. Would you prefer a significance level of 0.10 or 0.01 for your test? Explain. (Hint: See discussion just before Example 10.7.)