Suppose city police and paramedics know that the 95% confidence interval on the
ID: 3306068 • Letter: S
Question
Suppose city police and paramedics know that the 95% confidence interval on the proportion of calls for drug overdoses that end in fatalities is (0.775, 0.792).
What must be the value of , the point estimate for the proportion of calls for drug overdoses that end in fatalities?
What is the critical score that would be used to calculate the 95% confidence interval?
When can you use a T-score to calculate a confidence interval for a proportion?
Use the information you have for the two-sided 95% confidence interval to determine the level of confidence you would have if you were told that 0.775 is the one-sided lower bound for the confidence interval on the proportion of calls for drug overdoses that end in fatalities?
Explanation / Answer
1. the point estimate for the proportion of calls for drug overdoses that end in fatalities is the midpoint of the upper and lower bounds = (.775+.792)/2 = .7835
2.The critical score used to calc. 95% interval is 1.96
3. When the sample size is less than 30, then we should use t-score
4. This part is unclear as the level of confidence is asked. It is already defined at 95%