Stata
From Wikipedia, the free encyclopedia
| Stata | |
|---|---|
 Stata 10.0 on Windows |
|
| Developed by | Statacorp |
| Latest release | 10.0 / Summer 2007 |
| OS | Windows, Mac OS X, Unix, Linux |
| Genre | statistical analysis |
| License | proprietary |
| Website | www.stata.com |
Stata is a general-purpose statistical software package created in 1985 by StataCorp. It is used by many businesses and academic institutions around the world. Most of its users work in research, especially in the fields of economics, sociology, political science, and epidemiology.
Stata's full range of capabilities includes:
- Data management
- Statistical analysis
- Graphics
- Simulations
- Custom programming
The name "Stata" was formed by blending "statistics" and "data"; it is not an acronym.
Contents |
[edit] User interface
Since version 8.0, Stata has included a graphical user interface which uses menus and dialog boxes to give access to nearly all built-in commands. This generates code which is always displayed, easing the transition to the command line interface and more flexible scripting language. The data set can be viewed or edited in spreadsheet format, but this must be closed before other commands are executed.
[edit] Data structure and storage
Stata can only open a single data set at any one time. Stata holds the entire data set in (random-access or virtual) memory, which limits its use with extremely large data sets. This is mitigated to some extent by efficient internal storage, as there are integer storage types which occupy only one or two bytes rather than four, and single-precision (4 bytes) rather than double-precision (8 bytes) is the default for floating-point numbers.
The data set is always rectangular in format, that is, all variables hold the same number of observations (in more mathematical terms, all vectors have the same length, although some entries may be missing values).
[edit] Extensibility
Stata is unusual among commercial statistics packages in allowing user-written commands, distributed as so called ado-files, to be straightforwardly downloaded from the internet which are then indistinguishable to the user from the built-in commands. In this respect, Stata combines the extensibility more often associated with open-source packages with features usually associated with commercial packages such as software verification, technical support and professional documentation. Some user-written commands have later been adopted by StataCorp to become part of a subsequent official release after appropriate checking, certification and documentation.
[edit] User community
Stata has an active email list (Statalist, over 1000 messages per month), to which StataCorp employees regularly contribute. Statalist is maintained by Marcello Pagano, Harvard School of Public Health not by StataCorp itself. Articles about the use of Stata and new user-written commands are published in the quarterly peer-reviewed Stata Journal. User group meetings are held annually in the USA, the UK, Germany and Italy, and less frequently in several other countries.
[edit] Example Stata code
To perform logistic regression of y on x:
logistic y x
To display a scatter plot of y against x restricted to values of x below 10:
scatter y x if x < 10
[edit] See also
[edit] External links
- Official Stata website
- Stata Journal
- Stata Gentle Introduction - Stata Introduction basic to advanced statistical procedures
- Extensive Introduction to Stata - Kit Baum (Boston College)
- UCLA Stata Portal
- UCLA ATS Resources to help you learn Stata - Resources for learning Stata
- UCLA ATS Techical Reports - See Technical Report #1. Strategically using General Purpose Statistics Packages: A Look at Stata, SAS and SPSS
- Stata Highlights Page - Demonstrates how Stata can be used for several basic and advanced statistical procedures
- Ideas Repec Statistical Software Components - The main archive of user-written add-on programs (ado-files) for Stata
