You can download the example data files from this tidbit (as well as all of the other tidbits) as shown below. These will download all of the example data files into the current folder on your computer. (If you have done this before, then you may need to specify net get stowdata, replace to overwrite the existing files.
If you have thoughts on this Stata Tidbit of the Week, you can post a comment. You can also send me an email at MichaelNormanMitchell and then the at sign and gmail dot com. If you are receiving this tidbit via email, you can find the web version at http://www.michaelnormanmitchell.com/ . ]]>net from http://www.MichaelNormanMitchell.com/storage/stowdata net get stowdata
While many people and organizations host their user written Stata programs on their own web sites, the SSC archive (which is often called the Boston College Archive) is one of the largest (if not in fact the largest) repository of Stata programs contributed by Stata enthusiasts from all over the world. The ssc command, which is built into Stata, is a convenience command that easily connects you to this repository.
For example, if you type the ssc hot command, shown below, you will see the top 10 packages that have been recently downloaded. The output below shows the output that I saw executing the command today (your results will vary as the downloads for packages change over time).
. ssc hot Top 10 packages at SSC Feb2011 Rank # hits Package Author(s) ---------------------------------------------------------------------- 1 4404.1 outreg2 Roy Wada 2 3098.8 estout Ben Jann 3 1652.5 ivreg2 Christopher F Baum, Mark E Schaffer, Steven Stillman 4 1470.2 psmatch2 Barbara Sianesi, Edwin Leuven 5 1034.5 gllamm Sophia Rabe-Hesketh 6 1025.3 ranktest Mark E Schaffer, Frank Kleibergen 7 910.8 xtabond2 David Roodman 8 749.8 tabout Ian Watson 9 706.8 xtivreg2 Mark E Schaffer 10 630.0 tabstatmat Austin Nichols ---------------------------------------------------------------------- (Click on package name for description)
You can click on the names of the packages to view
its associated help file. Viewing these different help files
gives you a quick sense of the range, scope, and utility
of the programs located at SSC. (Note the names of the packages
in the output above are hot-linked to their online help files using
the technique illustrated in the tidbit from last week).
You are not limited to just viewing the top 10 packages. For example,
you can use the n() option, as illustrated below, to control
how many packages you see. The example below shows the
top 100 packages recently downloaded (the output is omitted).
You can see the packages that have been created or revised in
the last month with the ssc new command.
When I executed this command, approximately 50 commands
were listed that have been created or updated in the last month.
This illustrates how lively the activity is with respect to
updates and new contributions to the ssc archive. Suppose that, after perusing the output of ssc new
or ssc hot that you find decide that you want
to install a package, for example the package called
outreg2. You can then simply type
and that package is downloaded and installed. You can
then begin using the programs described in the program.
You can view the help file by typing
You can learn more about the SSC archive with the
help ssc command.
You can download the example data files from this tidbit
(as well as all of the other tidbits) as shown below.
These will download all of the example data files into
the current folder on your computer. (If you have done this
before, then you may need to specify net get stowdata, replace
to overwrite the existing files.
. ssc hot, n(100)
. ssc new
. ssc install outreg2
. help outreg2
If you have thoughts on this Stata Tidbit of the Week, you can
post a comment. You can also send me an email at MichaelNormanMitchell
and then the at sign and gmail dot com.
If you are receiving this tidbit via email, you can find
the web version at
http://www.michaelnormanmitchell.com/ .
net from http://www.MichaelNormanMitchell.com/storage/stowdata
net get stowdata
You can use this as a means of displaying the help file for SSC programs within your web site or perhaps for sending the link of a help file to a friend. For more information about the SSC archive, see help ssc.
You can download the example data files from this tidbit (as well as all of the other tidbits) as shown below. These will download all of the example data files into the current folder on your computer. (If you have done this before, then you may need to specify net get stowdata, replace to overwrite the existing files.
If you have thoughts on this Stata Tidbit of the Week, you can post a comment. You can also send me an email at MichaelNormanMitchell and then the at sign and gmail dot com. If you are receiving this tidbit via email, you can find the web version at http://www.michaelnormanmitchell.com/ . ]]>net from http://www.MichaelNormanMitchell.com/storage/stowdata net get stowdata
To display the help associated with regress postestimation you can specify either http://www.stata.com/help.cgi?regress postestimation (with a space) or http://www.stata.com/help.cgi?regress_postestimation (with an underscore). If you specify a term that is not the name of a help file, the web page will give you the opption to view the table of contents of the help files, or to search for the term you specified.
I can think of a few instances where this can be useful. Maybe you want to point to a Stata help file from within one of your web pages. Or, perhaps you might want to send an email to a friend or colleague (who might not have Stata) with a link pointing to a particular help file in Stata.
You can download the example data files from this tidbit (as well as all of the other tidbits) as shown below. These will download all of the example data files into the current folder on your computer. (If you have done this before, then you may need to specify net get stowdata, replace to overwrite the existing files.
If you have thoughts on this Stata Tidbit of the Week, you can post a comment. You can also send me an email at MichaelNormanMitchell and then the at sign and gmail dot com. If you are receiving this tidbit via email, you can find the web version at http://www.michaelnormanmitchell.com/ . ]]>net from http://www.MichaelNormanMitchell.com/storage/stowdata net get stowdata
For more information about the features in this update, you can type help whatsnew in the Stata command window.
You can download the example data files from this tidbit (as well as all of the other tidbits) as shown below. These will download all of the example data files into the current folder on your computer. (If you have done this before, then you may need to specify net get stowdata, replace to overwrite the existing files.
If you have thoughts on this Stata Tidbit of the Week, you can post a comment. You can also send me an email at MichaelNormanMitchell and then the at sign and gmail dot com. If you are receiving this tidbit via email, you can find the web version at http://www.michaelnormanmitchell.com/ . ]]>net from http://www.MichaelNormanMitchell.com/storage/stowdata net get stowdata
The result is that the ado files can be more recent than the executable, and until the executable is updated, some commands will not work because they are newer than the executable. To avoid this, I have started doing the updates in a different order. First, I use the
. update executuable
command to update the Stata executable file. I make sure that the update of the executable, if any, is complete. This can include using the update swap command and restarting Stata. Then, after the executable has been updated, I type
. update ado
This updates any of the ado files. After that is complete, I then run the
. update utilities
command. This updates Stata utilities including the Stata PDF documentation. This last step can take a while if there are many PDF files that need to be updated. However, I can pass the baton at this stage because I know that the executable and ado files have both been updated properly. This takes a bit longer, but ensures that the update is fully successful. For more information, you can see help update.
You can download the example data files from this tidbit (as well as all of the other tidbits) as shown below. These will download all of the example data files into the current folder on your computer. (If you have done this before, then you may need to specify net get stowdata, replace to overwrite the existing files.
If you have thoughts on this Stata Tidbit of the Week, you can post a comment. You can also send me an email at MichaelNormanMitchell and then the at sign and gmail dot com. If you are receiving this tidbit via email, you can find the web version at http://www.michaelnormanmitchell.com/ . ]]>net from http://www.MichaelNormanMitchell.com/storage/stowdata net get stowdata
Lately I have been working with some very large datasets and have been interested in how long Stata commands take to complete. The set rmsg on command has been useful for showing how long each command takes to execute, as well as the time it completed. To turn on return messages, you can type
To illustrate the effect of this command, let's use the auto dataset and the run a logistic regression.. set rmsg on
. sysuse auto (1978 Automobile Data) r; t=0.00 10:52:02 . logit foreign gear_ratio displacement turn length weight Iteration 0: log likelihood = -45.03321 Iteration 1: log likelihood = -21.846131 Iteration 2: log likelihood = -16.826028 Iteration 3: log likelihood = -15.938989 Iteration 4: log likelihood = -15.883186 Iteration 5: log likelihood = -15.88236 Iteration 6: log likelihood = -15.88236 Logistic regression Number of obs = 74 LR chi2(5) = 58.30 Prob > chi2 = 0.0000 Log likelihood = -15.88236 Pseudo R2 = 0.6473 ------------------------------------------------------------------------------ foreign | Coef. Std. Err. z P>|z| [95% Conf. Interval] -------------+---------------------------------------------------------------- gear_ratio | 3.536476 1.799346 1.97 0.049 .0098232 7.063128 displacement | -.0371318 .033608 -1.10 0.269 -.1030023 .0287388 turn | -.5515612 .242733 -2.27 0.023 -1.027309 -.0758133 length | .1025261 .0834969 1.23 0.219 -.0611249 .2661771 weight | -.0001706 .0027558 -0.06 0.951 -.005572 .0052307 _cons | -3.973186 10.60993 -0.37 0.708 -24.76827 16.8219 ------------------------------------------------------------------------------ r; t=0.48 10:52:33
Each command ends with a return message that begins with r; and then shows the amount of time it took to execute the command and when the command completed. The sysuse command took almost no time at all (less than a tenth of a second). The logit command took .48 seconds and completed at 10:52am. This can be useful for seeing how long a particular command takes to complete. This setting will also show how long a do-file takes to complete (and the time it completed).
If you want to make this setting permanent, you can type set rmsg on, permanently and Stata will remember this setting for future Stata sessions.
For more information, you can see help rmsg.
You can download the example data files from this tidbit (as well as all of the other tidbits) as shown below. These will download all of the example data files into the current folder on your computer. (If you have done this before, then you may need to specify net get stowdata, replace to overwrite the existing files.If you have thoughts on this Stata Tidbit of the Week, you can post a comment. You can also send me an email at MichaelNormanMitchell and then the at sign and gmail dot com. If you are receiving this tidbit via email, you can find the web version at http://www.michaelnormanmitchell.com/ . ]]>net from http://www.MichaelNormanMitchell.com/storage/stowdata net get stowdata
You can begin a command log with the cmdlog command, for example...
opens up a log file named mycommands.txt. Note that the extension for command files is .txt, emphasizing that they are text files.. cmdlog using mycommands
Now, every command that you type (and just the commands) will be saved in the file mycommands.txt.
When you want to close the file, you can type the command.
. cmdlog close
The log then contains all of the commands that you typed after opening the command log. Here is an example.
. type mycommands.txt sysuse auto describe summarize
If you exit Stata before closing the command log file, Stata will close the file for you. You can have a command log and a regular log open at the same time. For more information, see help log.
You can download the example data files from this tidbit (as well as all of the other tidbits) as shown below. These will download all of the example data files into the current folder on your computer. (If you have done this before, then you may need to specify net get stowdata, replace to overwrite the existing files.
If you have thoughts on this Stata Tidbit of the Week, you can post a comment. You can also send me an email at MichaelNormanMitchell and then the at sign and gmail dot com. If you are receiving this tidbit via email, you can find the web version at http://www.MichaelNormanMitchell.com/ . ]]>net from http://www.MichaelNormanMitchell.com/storage/stowdata net get stowdata
To recap from last week, we saw a do-file that looked like the following.
. capture log close . log using mergefiles, replace * Some commands here. . log close
Now, imagine that we wanted to write a do-file that would analyze our data. It would include a long set of tabulations, a long set crosstabulations, and then a long set of regressions. Say the do-file was named analyze.do. The contents of the do-file might look like this.
. capture log close . log using analyze, replace * Some commands here. . log close
But suppose we also wanted to separate the output into three separate log files, the tabulations, the crosstabs, and the regressions. We could do so like this.
. capture log close . log using analyze, replace capture log close logtab log using tab, replace name(logtab) * Tabulation commands here. log close logtab capture log close logxtab log using xtab, replace name(logxtab) * Cross tabulation commands here. log close logxtab capture log close logreg log using reg, replace name(logreg) * Regression commands here. log close logreg . log close
Running this do-file would create the overall log file named analyze.smcl that would contain the commands and output from the entire do-file. The log file tab.smcl would contain just the output of the tabulations, xtab.smcl would contain the output of the cross tabulations, and reg.smcl would contain the output of the regression analyses. The log file for the tabulations includes the name(logtab) option that specifies that the logname is logtab. The capture log close logtab and log close logtab commands specifically refer to that log file, letting Stata know that we are referring to the log file with the logname of logtab
At any one time, this do-file has up to two log files active at once. You can have up to five SMCL logs and five text (.log) files active at one time, probably more than you would ever need. For more information, see help log.
You can download the example data files from this tidbit (as well as all of the other tidbits) as shown below. These will download all of the example data files into the current folder on your computer. (If you have done this before, then you may need to specify net get stowdata, replace to overwrite the existing files.
If you have thoughts on this Stata Tidbit of the Week, you can post a comment. You can also send me an email at MichaelNormanMitchell and then the at sign and gmail dot com. If you are receiving this tidbit via email, you can find the web version at http://www.MichaelNormanMitchell.com/ . ]]>net from http://www.MichaelNormanMitchell.com/storage/stowdata net get stowdata
A do-file allows you to simplify the process of repeating a series of Stata commands. However, without a log file, you have no permenent record of the results of running a do-file. This is why I create a log file as part of almost every do-file that I create. Suppose I create a do-file named mergefiles.do. It will look something like this.
. log using mergefiles, replace * Some commands here. . log close
The first log using command creates a log file with the name mergefiles.smcl (the same name as the do-file), and will overwrite it if it already exists. Then, some commands are executed, followed by the log close command. The only fly in the ointment is if the do-file encounters an error, in which case the log close command would not be executed, leaving the log file open. When the do-file is executed again, the log using command will result in an error, because the log is already open. So, my standard do-file looks more like the following.
. capture log close . log using mergefiles, replace * Some commands here. . log close
The capture log close command forces the log to be closed, whether it was open or not. Then, the log using command opens the log file, the commands are executed, and the log file is closed. This is a bare bones outline for a do-file to make sure you always have a permenent record of running the do-file. And, if you change the name of the do-file, be sure to change the name of the log file within the log using command. For more information, see help log.
Next week I will discuss how to have more than one log file active at a time.
You can download the example data files from this tidbit (as well as all of the other tidbits) as shown below. These will download all of the example data files into the current folder on your computer. (If you have done this before, then you may need to specify net get stowdata, replace to overwrite the existing files.
If you have thoughts on this Stata Tidbit of the Week, you can post a comment. You can also send me an email at MichaelNormanMitchell and then the at sign and gmail dot com. If you are receiving this tidbit via email, you can find the web version at http://www.MichaelNormanMitchell.com/ . ]]>net from http://www.MichaelNormanMitchell.com/storage/stowdata net get stowdata