A researcher wants to calculate the 98% confidence interval on the variable prior arrests. She draws a sample of 130 inmates who have a mean of 3.4 prior arrests and a standard deviation of 1.1 prior arrests. What is the value of t that she would use in the formula? What is the value of the standard error in the formula?
Added by Alejandro H.
Step 1
The degrees of freedom can be calculated using the formula: \[ df = n - 1 \] where \( n \) is the sample size. In this case, \( n = 130 \), so: \[ df = 130 - 1 = 129 \] Show more…
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