# Statistics Lectures - 20: One Sample z-Test & One Sample t-Test

A series of free Statistics Lectures with lessons, examples & solutions in videos.

This is page twenty of the series of free video lessons, “Statistics Lectures”. These lectures discuss various types of samples t-test, covering one sample z-test and one sample t-test.

### Statistics - Lecture 59: One Sample z-Test

1. Define Null and Alternative Hypothesis
2. State Alpha
3. State Decision Rule
4. Calculate Test Statistic
5. State Results
6. State Conclusion

### Statistics - Lecture 60: One Sample z-Test For Proportions

Example:
A survey claims that 9 out of 10 doctors recommend aspirin for their patients with headaches. To test this claim, a random sample of 100 doctors is obtained. Of these 100 doctors, 82 indicate that they recommend aspirin. Is this claim correct? Use alpha = 0.05

### Statistics - Lecture 61: One Sample t-Test

z-Tests are commonly done when the population standard deviation is known. t-Tests are commonly done when the population standard deviation is unknown. We use the t-distribution because the unknown population standard deviation is now a value we must estimate. 