At the beginning of
2003, Stata Corp. released a major new version of their
software. Stata Version
8.0 contains a point-and-click interface and has greatly expanded
graphics capabilities. The
point-and-click interface allows users to generate most Stata commands
without knowing the precise command syntax.
Conventional text-based commands are also generated by this
interface that may be saved in do files or recalled from the Review
Window as in Version 7.
Most of the changes in Version 8 syntax are in
the graph commands. These
commands introduce many new features but can result in much longer
command lines. You may
use the old graph syntax by replacing the Version 7 graph
command by the graph7
command. For example, a
scatter plot in Version 7 with
x-axis labels at 1, 3, 5, and 7 would be written
graph
x y, xlabel(1 3 to 7)
The equivalent Version 8 command is
scatter
x y, xlabel(1(2)7)
However, Version 8 will also accept
graph7
x y, xlabel(1 3 to 7)
Substituting graph7
for graph allows almost all of the graph commands
given in the text to run under Version 8 without any other
modifications.
One difficulty with Version 8 is that it can
generate very long commands. These
commands are easier to read if they are written over multiple lines.
Stata interprets three consecutive slashes at the end of a line
to indicate that the next line is a continuation of the preceding one.
Hence,
by
treat: summarize age, detail
and