SOLUTION: Listed below are student evaluation ratings of​ courses, where a rating of 5 is for​ "excellent." The ratings were obtained at one university in a state. Construct a confidence

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Question 1182690: Listed below are student evaluation ratings of​ courses, where a rating of 5 is for​ "excellent." The ratings were obtained at one university in a state. Construct a confidence interval using a 98​% confidence level. What does the confidence interval tell about the population of all college students in the​ state?
4.0​, 3.2​, 4.0​, 4.6​, 3.1​, 4.3​, 3.5​, 4.7​, 4.7​, 4.0​, 4.0​, 3.8​, 3.4​, 3.8​, 3.5
What is the confidence interval for the population mean μ​?
__ < μ < __ ​(Round to two decimal places as​ needed.)

Answer by Boreal(15235)   (Show Source): You can put this solution on YOUR website!
Assuming one may treat these as interval data,
the mean is 3.907
s=0.513
there are 15 items, so a t(0.99, df=14) is 2.624
the half-interval is 2.624*0.513/sqrt(15)=0.348
the interval is (3.559, 4.255)
This suggests with high confidence (90%) the true mean, unknown, is in this interval.

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