Lesson 14 covers Inferences on the Population Mean when the Population Standard Deviation is **known**. The resulting hypothesis test and confidence interval are based on the Z-distribution, also called the Standard Normal Distribution. Lesson 15 covers Inference on the Population Mean when the Population Standard Deviation is **unknown.** The sample standard deviation, S, will be used as an estimator for sigma, the population standard deviation, but when that occurs the test statistic is not Z, but t and the confidence interval form is also based on t, not Z. Here are some details, Class Notes Z test and t test, with CI equations .

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February 28, 2020 – 9:14 am
Exam Two is Thursday, March 5, 2020. Begin to study by using this exam two review that represents all the types of distributions covered since exam one. In the exam two review KEY the answers are provided, but additionally it indicates which past exam that the question came from. Study Up! Make an A!