To begin, z-tests are usually done for large samples (n greater than 30). The purpose is to determine whether there is a difference between a sample compared to an entire population. To perform a z test, the standard deviation of the population is usually known.
A rental car company claims the mean time to rent a car on their website is 60 seconds with a standard deviation of 30 seconds. A random sample 36 customers attempted to rent a car on the website. The mean time to rent was 75 seconds. Is this enough evidence to contradict the company's claim?
Since we have an n value of 36 in the above example with a known population standard deviation and we are aiming to find a ...
This 500 word response provides explanations and original examples for several types of statistical tests.