1. The principal randomly selected six students to take an aptitude test. Their scores were: 81.6 72.0 81.1 86.4 70.2 83.1 The sample standard deviation is s = 6.47 but you will have to calculate the sample mean. (a) Determine a 90% confidence interval for the mean score for all students. (b) Raise the level of confidence to 99%, and show the effect on the confidence interval.

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A:

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Q:

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Q: what is the correct choice

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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.