Suppose that 100 randomly selected members of the Karaoke channel were asked how much time they typically spend on the site during the week. The sample mean X, with line above it was found to be 3.8 hours. Assume that the population standard deviation is known to be 2.9. a) Cary Oakey computes the 95% interval for the average time on the sote as 3.8 +/- 1.96 (2.9/100). What is his mistake? b) He corrects this mistake and then states that 95% of the members spend between 3.23 and 4.37 hours a week on the site." What is wrong with his interpretation of this interval? c) The margin of error is slightly higher than half an hours. To reduce this to roughly 15 minutes, cary says that the sample size needs to be doubled to 200. What is wrong with this statement?

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Estimation

A new framework of data analysis where the new statistical methods are used for interpreting the results and analyzing the data is known as estimation in statistics.