A researcher compares the effectiveness of two different instructional methods for teaching anatomy. A sample of 131 students using Method 1 produces a testing average of 88.1. A sample of 142 students using Method 2 produces a testing average of 87.1. Assume that the population standard deviation for Method 1 is 11.46, while the population standard deviation for Method 2 is 9.78. Determine the 95% confidence interval for the true difference between testing averages for students using Method 1 and students using Method 2. Step 1 of 2:  Find the critical value that should be used in constructing the confidence interval.

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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.