Find the critical value zα/2 needed to construct a(n) 79% confidence interval.

A sample of 66 night-school students' ages is obtained in order to estimate the mean age of night-school students. x = 24.7 years. The population variance is 18. (a) Give a point estimate for u. (Give your answer correct to one decimal place.) (b) Find the 95% confidence interval for u. (Give your answer correct to two decimal places.) Lower Limit Upper Limit (c) Find the 99% confidence interval for u. (Give your answer correct to two decimal places.) Lower Limit Upper Limit

Suppose you have a model Y = B₁ + B₂X₂ + uż that satisfies all CNLRM assumption with 8 observations, and the o2 = 36. What is the 95% confidence interval of o²? (17.17, 98.19) (18.63, 132.46) (17.75, 145.56) (14.95, 174.62) Do not have enough information

Suppose we are making predictions of the dependent variable y for specific values of the independent variable x using a simple linear regression model holding the confidence level constant. Let Width (C.I) = the width of the confidence interval for the average value y for a given value of x, and Width (P.I) = the width of the prediction interval for a single value y for a given value of x. Which of the following statements is true? Width (C.I) = 0.5 Width (P.I) Width (C.I) = Width (P.I) Width (C.I) > Width (P.I) Width (C.I) < Width (P.I)

In a large scale study of energy conservation in single family homes, 20 homes were randomly selected from homes built in a housing development in southern England. Ten of the houses, randomly selected from the 20 houses selected for the study, were constructed with standard levels of insulation (70 mm of roof insulation and 50 mm of insulation in the walls). The other 10 houses were constructed with extra insulation (120 mm of roof insulation and 100 mm of insulation in the walls). Each house was heated with a gas furnace and energy consumption was monitored for eight years. The data shown below give annual gas consumption in MWh for each of the 20 houses. Standard Insulation Extra Insulation 13.8 15.1 17.8 13.9 18.0 15.9 17.3 17.2 16.9 15.2 19.9 13.8 13.6 11.3 17.6 13.2 15.9 18.8 12.3 14.0 Sample means Sample Standard Deviation 16.31 14.84 2.38 2.12

What critical value t∗t∗ from Table C would you use for a confidence interval for the mean of the population in each of the following situations?   (a)96% confidence interval based on n = 25 observations.(b) A 95% confidence interval from an SRS of 17 observations.(c) A 90% confidence interval from a sample of size 13.

find the critical value Z of alpha over 2 used to construct a confidence interval of 94%

Suppose a marketing company randomly surveyed 404 households and found that in 214 of them, the woman made the majority of the purchasing decisions. Construct a 90% confidence interval for the population proportion of households where the women make the majority of the purchasing decisions.p'=α2=zα2=Margin of Error: E=We are 90% confident that the proportion of households in the population where women make the majority of purchasing decisions is between___ and ___.

Consider a company is looking for a new location to mine for gold, and they send a surveyor out to different locations to test for the presence of gold. The surveyor will continue testing locations until they find a location that tests positive for gold, then they will consider that location a success and recommend the new site be built in that location. The probability they find gold at any one of the preliminary locations is 0.05. a) What is the probability that the surveyor will find gold at the first location they test? b) What is the probability that the surveyor will need to test more than 5 locations? c) If it cost the company $150 for each site they test, what is the average cost for them to find a new location with gold present to build a mine?

Find the critical values x1-a/2 for a 98% confidence level and a sample size of n = 25. and α/2 1-a/2 (Round to three decimal places as needed.)