Add description of variables shown in the data matrix

Author: mine-cetinkaya-rundel

Chp 1/1-2_data_basics/1-2_data_basics.tex

@@ -6,6 +6,24 @@ \section{Data basics}
 
 \subsection{Observations and variables}
 
+\begin{frame}
+\frametitle{Classroom survey}
+
+A survey was conducted on students in an introductory statistics course. Below are a few of the questions on the survey, and the corresponding variables the data from the responses were stored in:
+
+\begin{itemize}
+\item \var{gender}: What is your gender? 
+\item \var{intro\_extra}: What is your gender? 
+\item \var{sleep}: How many hours do you sleep at night, on average?
+\item \var{bedtime}: What time do you usually go to bed?
+\item \var{countries}: How many countries have you visited?
+\item \var{dread}: On a scale of 1-5, how much do you dread being here?
+\end{itemize}
+
+\end{frame}
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
 \begin{frame}
 \frametitle{Data matrix}