frontier

News

• News about the frontier project are available at the project's R-Forge site.

What is frontier?

• frontier is an extension package for the "language and environment for statistical computing and graphics" called R.
• frontier estimates stochastic frontier production and cost functions by maximum likelihood. Two specifications are available: the error components specification with time-varying efficiencies (Battese and Coelli, 1992) and a model specification in which the firm effects are directly influenced by a number of variables (Battese and Coelli, 1995).
• frontier includes an improved version of the Fortran source code of Tim Coelli's software FRONTIER 4.1 and hence, provides the same features as FRONTIER 4.1. A comprehensive documentation of FRONTIER 4.1 is available in the file "Front41.pdf" that is included in the archive "FRONT41-xp1.zip", which is available at http://www.uq.edu.au/economics/cepa/frontier.htm. This documentation is helpful also to users of the frontier package, because this package is based on the FRONTIER 4.1 software.
• Furthermore, frontier includes functions for:
  • writing input files for FRONTIER 4.1 (function "front41WriteInput")
  • reading output files of FRONTIER 4.1 (function "front41ReadOutput")

What are the differences between FRONTIER 4.1 and the R package frontier?

• FRONTIER 4.1 is a stand-alone software, while the R package frontier is an add-on package to the software R.
• FRONTIER 4.1 only runs under MS-Windows, while the R package frontier runs under all major operating systems.
• Running FRONTIER 4.1 requires the preparation of an instruction file and a data file and possibly the modification of a file with settings, while the R package frontier has a much simpler user interface.
• The coefficients and efficiencies estimated by the R package frontier are directly available for further calculations.
• The Fortran code in FRONTIER 4.1 includes a bug that in specific circumstances can result in wrong estimates, while this bug has been fixed in the R package frontier.
• The Fortran code in the R package frontier has been optimised for numerical stability so that the estimates are numerically more stable.
• The user can control more details of the estimation procedure and the calculation of the efficiency estimates when using the R package frontier.
• The R package frontier can calculate the marginal effects of the "z variable" on the efficiency estimates when using the efficiency effects model of Battese and Coelli (1995).

Who has written frontier?

• Tim Coelli has written the Fortran source code, which is the main component of this package.
• Arne Henningsen has improved the Fortran code, included it into an R package, and has written the R interface.

Where can I get frontier?

• The released version is available on CRAN
  • You can download the source code, binaries for MacOS X and MS-Windows, and the reference manual from http://cran.r-project.org/web/packages/frontier/.
  • You can install the package by typing at the R prompt (if you have internet access):

     install.packages( "frontier" )

• The current development version is available on R-Forge
  • You can download the source code and binaries for MacOS X and MS-Windows from http://r-forge.r-project.org/R/?group_id=275.
  • You can install the package by typing at the R prompt (if you have internet access):

     install.packages( "frontier", repos="http://R-Forge.R-project.org" )

Under which license is frontier released?

• Under the GNU General Public License (GPL)

Where can I ask questions, report bugs, or suggest new features?

• Please use a forum or "tracker" at the project's R-Forge site.