frontierQuad {frontier}R Documentation

Quadratic or Translog Frontiers

Description

This is a convenient interface for estimating quadratic or translog stochastic frontier functions using frontier.

Usage

frontierQuad( yName, xNames, shifterNames = NULL, zNames = NULL,
   data, quadHalf = TRUE, ... )

Arguments

yName string: name of the endogenous variable.
xNames a vector of strings containing the names of the X variables (exogenous variables of the production or cost function) that should be included as linear, quadratic, and interaction terms.
shifterNames a vector of strings containing the names of the X variables that should be included as shifters only (not in quadratic or interaction terms).
zNames a vector of strings containing the names of the Z variables (variables explaining the efficiency level).
data a (panel) data frame that contains the data; if data is a usual data.frame, it is assumed that these are cross-section data; if data is a panel data frame (created with plm.data), it is assumed that these are panel data.
quadHalf logical. Multiply the quadratic terms by one half?
... further arguments passed to frontier.

Value

frontierQuad returns a list of class frontierQuad (and frontier) containing the same elements as returned by frontier and additionally the element quadHalf which is equal to the argument quadHalf.

Author(s)

Arne Henningsen

See Also

frontier.

Examples

   # example included in FRONTIER 4.1 (cross-section data)
   data( front41Data )
   front41Data$logOutput  <- log( front41Data$output )
   front41Data$logCapital <- log( front41Data$capital )
   front41Data$logLabour  <- log( front41Data$labour )

   translog <- frontierQuad( yName = "logOutput",
      xNames = c( "logCapital", "logLabour" ),
      data = front41Data )
   translog

[Package frontier version 0.991-0 Index]