10 One sample tests
One sample tests are for cases in which you have one sample, and what to determine if it belongs to a certain population. Like:
is it the gas in Hawaii significantly more expensive than the rest of the USA?.
is a 10 year old girl taller than expected?
These types of questions can be answered with either the Z-test or the T-Test, which we will introduce in this chapter. Both of these tests are suited for one-sample test, but the Z-test is used for cases in which you know the population standard deviation (SD) and your sample size is larger than 30 observations. If on the contrary, you do not know your population SD or your sample size is smaller than 30 observations, then you used the T-Test.
Figure 10.1: Z-score fucntion
At the end of this chapter, you are expected to:
Run a one sample Z-test and interpret its results from R.
Run a one sample T-test and interprets its results from R.