Refer to the stock you selected in Module 1. Using the same downloaded data, build a 95 percent confidence interval for the daily stock volume using your downloaded data. What does this confidence interval mean?

Why might dedecision-makerse interested in such an interval?

 

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Confidence Interval for a Population Proportion From a sample proportion, we can calculate the standard deviation of the sampling distribution (the standard error of the estimate), and use the standardized normal distribution to get a z multiple, using the Excel function NORMSINV. The margin of error is the z multiple times the standard error, and it is how far the confidence interval extends on each side of the point estimate. Input Variables -- Sample Proportion (p-bar) 0.45 <-- Input the appropriate number for your situation Sample Size (n) 1263 <-- Input the appropriate number for your situation Confidence Level: 0.95 <-- Input the appropriate number for your situation Intermediate Calculations -- Standard Error of the Estimate: 0.0140 Prob. in One Tail for this Conf Level: 0.025 Prob. to use in NORMSINV: 0.975 Z Multiple: 1.960 Confidence Interval -- Lower limit: 0.4226 We can be 95% confident that the population proportion Upper limit: 0.4774 lies between 0.4226 and 0.4774 Margin of error: 0.0274 Confidence Interval for a Population Proportion From a sample proportion, we can calculate the standard deviation of the sampling distribution (the standard error of the estimate), and use the standardized normal distribution to get a z multiple, using the Excel function NORMSINV. The margin of error is the z multiple times the standard error, and it is how far the confidence interval extends on each side of the point estimate. Input Variables -- Sample Proportion (p-bar) 0.45 <-- Input the appropriate number for your situation Sample Size (n) 1263 <-- Input the appropriate number for your situation Confidence Level: 0.95 <-- Input the appropriate number for your situation Intermediate Calculations -- Standard Error of the Estimate: 0.0140 Prob. in One Tail for this Conf Level: 0.025 Prob. to use in NORMSINV: 0.975 Z Multiple: 1.960 Confidence Interval -- Lower limit: 0.4226 We can be 95% confident that the population proportion Upper limit: 0.4774 lies between 0.4226 and 0.4774 Margin of error: 0.0274

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General motors data from 30082013 to 30082018 The summary of this data is n 1260 Mean 1493073246 Std... View the full answer