Question

In: Statistics and Probability

1. In 1989, the average age of inmates on death row was 36.5 years of age,...

1. In 1989, the average age of inmates on death row was 36.5 years of age, according to data obtained from the U.S. Department of Justice. A sociologist believes that the average age of death-row inmates has changed since then. She randomly selects 40 death-row inmates and finds that their mean age is 38.9 years. Assuming that ages of death-row inmates vary with a standard deviation of 8.6 years,

a. Provide a point estimate (and the associated standard error) for the current average age of death-row inmates.

b. Provide a 95% two-sided confidence interval for the current average age of death-row inmates. Interpret the result.

c. Based on your interval in part b, does it look like this average has changed?

d. Provide a 90% upper bound confidence interval for the current average age of death-row inmates. Interpret the result.

e. Provide a 99% lower bound confidence interval for the current average age of death-row inmates. Interpret the result.

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orchestra answered 1 year ago
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