Exercise

# One-sample t-test

In the last exercise, you used the `t.test()`

function to derive a confidence interval. In this exercise, you will use this function to test if the population's mean amounts to a specific value.

You can get asked about **the one-sample t-test** if your future role involves testing a sample against *a specific benchmark*.

In this exercise, you will once again work with the `sleep`

dataset from the datasets package.

The dataset contains the following variables:

`group`

- indicates which drug has been given to a patient (either`1`

or`2`

),`extra`

- an increase in hours of sleep compared to control.

You will perform the one-sample t-test twice - once for the first group and once for the second group.

Instructions 1/3

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## Question

What is the null hypothesis of the one-sample t-test?

### Possible answers

The population's mean is different than a given value.

The underlying distribution is normal.

The population's mean equals the hypothesized mean.

The sample needs to be random.