This edition: Inference for One Mean
This lesson pursues a more realistic test of significance than the z test discussed in Lesson 15. In that lesson, you learned to use the ƶ test to determine whether or not a sample population mean is significantly different from the claimed population mean. The z-test assumes that we know the population standard deviation. In reality, we rarely know standard deviation. In this lesson, you will learn how researchers get around that problem by using a different test with more realistic parameters.