Many commands have a by option producing statistics for each group defined by a categorical variable.
| tabstat infmor , by(continent) | Summary statistics by continent |
| histogram urb, by(continent) | A histogram for each continent |
| graph box urb , by(continent) | Boxplot for each continent |
Another way of producing groupwise results is to use the BY prefix supported by most commands (one of the exceptions is the graph command.
The general syntax is:
by varlist1 [(varlist2)] [, sort] : stata_cmd bysort varlist1 [(varlist2)]: stata_cmd
BYSORT is a shortcut, as sorting on the group variable is a requirement for the command to work.
| bysort continent: stem urb | Stem and leaf plot for each continent. |