* SHAZAM code downloaded from UCLA Econ 143 (CAMERON) WebSite: 
* HTML file called e143sh5.htm, and should have 
*  been downloaded as colds.sha

* example of omitted variables bias in estimation:  religion and health
* colds= number of colds caught per year
* visits=number of visits to place of worship per month
* age=age of respondent

sample 1 12
read colds visits age
4 4 44
5 3 48
2 0 19
3 3 31
4 2 42
2 2 20
3 1 33
4 3 41
2 1 22
3 2 29
5 4 52
5 5 54