Answer Happy

Suppose that it was known that the level of activity of a particular enzyme on the heart of hamsters had a mean of 40 units. The researcher was interested in variations of activity in the heart, o2. Therefore, fifteen hamsters were randomly selected and given the enzyme. A summary from data gathered gave: , X; = 637 and 2 X = 27920. (a) What would you use as an appropriate pivotal function as a starting point for finding a confidence interval of the variance o?? Explain why this is a satisfactory pivotal function. (b) Without deriving it, state what is the underlying distribution associated with the pivotal function you selected in (a)? [You may assume the level of activity follows a normal distribution.] (c) Derive the 95% equal-tailed confidence interval for op. (d) For these data, calculate the 95% equal-tailed confidence interval for the standard deviation o.