---
title: "Sleep Study"
output: html_document
---


# Purpose

This document analyzes the `sleep` study dataset, which contains the results of an experiment with 2 sleep aid (soporific) drugs.

The variables contained are:

* **extra**: increase in hours of sleep compared to control drug
* **group**: drug given
* **ID**: patient ID



## The data set

Here are the data:




## Log-transforming the outcome

First, log-transforming the outcome **extra** was suggested:

But there are negative values, so we'll stick to leaving the outcome untransformed.

The mean of the untransformed variable **extra** is XXX.