A 95% confidence interval for the mean, μ, of a population is (13, 20) A 95% confidence interval for the mean, μ, of a population is (13, 20). Based on this interval: there is a 95% chance μ is in the interval. 95% of the observations lie in the interval. the method gives correct results 95% of the time.

We would like to construct a confidence interval to estimate the mean μ of some variable X. For a given sample size, which of the following combinations of confidence level will produce the shortest interval? 90% confidence, 95% confidence 99% confidence These three will have the same size interval

The manager at a movie theater would like to estimate the true mean amount of money spent by customers on popcorn only. He selects a simple random sample of 26 receipts and calculates a 92% confidence interval for true mean to be ($12.45, $23.32). The confidence interval can be interpreted to mean that, in the long run:   92% of similarly constructed intervals would contain the population mean. 92% of similarly constructed intervals would contain the sample mean. 92% of all customers who buy popcorn spend between $12.45 and $23.22.

A random sample of size n is collected from a population with standard deviation s. With the data collected, a 95% confidence interval is computed for the mean of the population. Which of the following would produce a new confidence interval with smaller width (smaller margin of error) based on these same data? Increase s. Use a smaller confidence level. Use a smaller sample size.

Suppose we have a 99% confidence interval of [8,10]. This means There is a 99% chance that the population mean is in the interval The probability that the population mean is in the interval is 0.99 99% of the data is in [8,10] Two are correct All are correct None of the above

Answers C,A,A,B,F