The current version of stata is Stata 10. Stata 10 is a statistical software system including
Stata for UNIX may be used on the central UNIX server, strauss, but stata is not available on copland. UNIX Stata is located at
/opt/bin/stata
The full-screen GUI stata is located at
/opt/bin/xstata
To access either of these two applications, type just the name of the application at the strauss prompt
stata
or
xstata
UNIX stata is available on strauss (not on
copland).
Stata for Windows is available in the Research & Data Management
Services (RDMS) lab. Check in the User Services office (002 Smith Hall) to get
an acoount on these machines.
This document describes use of Stata on UNIX.
Stata may be run (1) in a full-screen environment, (2) in line-prompt mode, or (3) batch mode.
Full-screen Mode. To run Stata interactively in full-screen mode, you must be logged onto your unix account using an X-window interface such as a SunRay, a UNIX Workstation, or an emulation of an X-window connection such as Exceed running on Windows or an xterm window running on a Mac. Or free software called Cygwin is a workable alternative to Exceed.
To start full-screen Stata, logon to strauss and type --
xstata
at the UNIX prompt. Three panes appear in a new window. Figure 1 shows an image of the Stata 10 window.
The Results window may be difficult to read, as implied by Figure 1. You may customize its appearance by clicking Edit/Preferences/General/Preferences/Results. Change "Color scheme:" from "Black background" to "White background" and change the font to Courier New, point size 12 (See Figure 1a).
The editor is the bottom right pane. Type Stata commands here. For example, type the following two lines --
sysuse auto, clear summarize
Figure 2 shows the results of these two commands. The upper left pane displays the Stata commands that were entered in the lower right pane. The lower left pane lists the names of the variables, and the Stata Results pane (upper right, default to black background) displays the output.
For example, to show a high-resolution scatterplot with overlaid linear-regression line, type --
graph twoway (lfit mpg weight) (scatter mpg weight)
The result looks like --
You may print the plot by issuing the print command -
print @Graph
or by clicking the right mouse button on the plot and releasing on "Print".
You may create a plot in an interactive mode or in a batch submission, as described below.
Line Mode. To run a prompted Stata session but without the full-screen window, type --
stata
at the UNIX prompt. The Stata prompt is a period located at the beginning of the command line. To exit Stata, type --
. exit
at the Stata prompt. If you have unsaved work in memory, Stata will refuse to exit. You can save your worksheet, then exit --
. save filename . exit
replacing filename with the name of your file.
Stata adds an extension of .dta to your filename.
Or you can force Stata to exit without saving your data by typing --
. exit, clear
at the Stata prompt.
You may enter data at the Stata prompt by typing the keyword input followed by a list of variable names. For example --
input price mpg weight
Stata responds with a sequence of numbered prompts (shown in red
below), one for each new observation. End the input with the keyword,
end
1. 4697 25 1930 2. 8814 21 4060 3. 3667 . 2750 4. 4099 22 2930 5. end
To list the data, type list at the Stata prompt --
. list
+----------------------+
| price mpg weight |
|----------------------|
1. | 4697 25 1930 |
2. | 8814 21 4060 |
3. | 3667 . 2750 |
4. | 4099 22 2930 |
+----------------------+
.
Variable names must --
Notes: (1) Variable names are case sensitive. (2) A period denotes a missing numeric value.
To add more observations, type input with no variable list, for example --
. input 5. 5079 24 2280 6. 5189 20 3280 7. 8129 21 2750 8. end .
List the cases again to confirm --
. list
+----------------------+
| price mpg weight |
|----------------------|
1. | 4697 25 1930 |
2. | 8814 21 4060 |
3. | 3667 . 2750 |
4. | 4099 22 2930 |
5. | 5079 24 2280 |
|----------------------|
6. | 5189 20 3280 |
7. | 8129 21 2750 |
+----------------------+
.
To get univariate descriptive statistics type --
. summarize
Variable | Obs Mean Std. Dev. Min Max
---------+-----------------------------------------------------
price | 7 5667.714 1997.448 3667 8814
mpg | 6 22.16667 1.94079 20 25
weight | 7 2854.286 688.7878 1930 4060
.
To record your session in a file, type --
. log using filename, text
substituting the name of your file for filename.
The text option is required to get a plain text file that
formats properly in a text editor such as pico. The log file will be
named filename.log. To stop recording commands and
output in the log, type --
. log close
Batch Mode. You can run a Stata job with your commands in a command file instead of typing them interactively at the Stata prompt. Stata expects a filename extension of .do for its command files. For example, suppose a command file named mpgtest.do contains the following commands --
sysuse auto, clear summarize graph twoway (scatter mpg weight) (lfit mpg weight) graph export mpgXweight.ps, replace shell xv mpgXweight.ps
To run Stata using this command file, type --
stata -b do mpgtest
The -b do flag indicates a batch run. The do keyword indicates to Stata to execute the commands in the file named after it, in this example, mpgtest.do. Stata assumes an extension of .do if you omit it. Output for this example is saved in a file called mpgtest.log. If your output is not written or not updated, check this .log file for diagnostics.
Plots do not automatically display on the terminal screen when running batch stata. You can display a plot saved during a batch run using a unix viewer such as ghostview or xv. This command file ends with a Stata shell command to display the plot using the UNIX application named xv. But It works only if you use an X-window connection to strauss.
You also can run a batch Stata job by using the UNIX redirection symbols, like this --
stata < mpgtest.do >! mpgtest.log
The advantage of using the UNIX redirection symbols is that you have complete control over the names of your command files and output files. But the disadvantage is that you cannot set the command delimiter.
The command to set the character that divides Stata commands is #delimit. This can be quite useful if you have commands that span more than one line, because it improves the readablity of your code. For example, to set it to the semicolon, put--
#delimit ;
at the top of your command file. Using the #delimit command, the previous example might be reformatted for easy readability like this --
#delimit ;
sysuse auto, clear;
summarize;
graph twoway
(scatter mpg weight)
(lfit mpg weight);
graph export mpgXweight.ps,
replace;
shell xv mpgXweight.ps;
However, the #delimit command is ignored unless you run the batch command file using the -b do flag.
To run the job in the background, use the &
character at the end of the command. For example --
stata -b do mpgtest &
There are several sources of additional information about Stata --
Help command:
help command name.Search command:
search search topic.To get started with help, type
helpwithout a command name.