/*
Exercise - Data Structure
Run the following command to load a data set from the U.S. Census

webuse census.dta, clear

- What year were these data collected?
- How many observations are there?  What is the unit of observation?
- Are there any string variables?  If so, which are they?
- Which variables have variable labels?
- Which variables have value labels?
- Which variables are categorical?  Which are continous measures?  Which are indicators?
- Where are there missing values in these data?

/*
Exercise - Elements of Stata Syntax: 
Create and run a do file using the auto data set.

- Write a command to browse domestic cars that get more than 25 miles per gallon and are known to have good repair records (rep78 greater than 3). 
- Then write a command to browse foreign cars that cost less than $5,000 and are not known to have poor repair records (rep78 less than or equal to 3). When browsing, include the variables used in the conditions so you can spot-check your results. 
- Explain why you handled missing values the way you did in both commands.
*/

/*
Exercise - Statistics Commands: 
Create and run a do file using the auto data set.

- Find the mean price of cars that get more than 25 miles per gallon. 
- Next compare that with the mean price of cars that get 25 miles per gallon or less.
Did American consumers in 1978 considered good gas mileage a negative or
a positive characteristic?

In another do file, run the following command to load a data set concerning mothers' health and
infants' birth weight.

webuse lbw, clear
- What type of variable is "low"?  What is the proportion of infants with
a low birth weight?
- What type of variable is "smoke"?  What is the proportion of mothers who
smoke during pregnancy?
- Is there a relationship between smoking status and low birth weight?
- What is the average age of a mother in these data?  What is the average age
for a nonsmoking mother?  a mother who smoked during pregnancy?
*/