translogRayEst: Estimate a Translog Ray Function

Description

Estimate a translog ray function with two endogenous variables, e.g. a ray production function with two outputs.

Usage

translogRayEst( yNames, xNames, data, shifterNames = NULL, ...)
## S3 method for class 'translogRayEst':
print( x, \dots )

Arguments

yNames

a vector of two character strings containing the names of the two dependent variables.

xNames

a vector of strings containing the names of the independent variables.

data

data frame containing the data (possibly a panel data frame created with plm.data).

shifterNames

a vector of strings containing the names of the independent variables that should be included as shifters only (not in quadratic or interaction terms).

an object of class translogRayEst.

...

further arguments of translogRayEst are passed to translogEst and possibly further to lm or

Value

A list of class translogRayEst (and translogEst) that is very similar to the object returned by translogEst. It additionally includes following objects:
distancethe distance from the origin (zero) to the point of the dependent variables.
thetathe direction from the origin (zero) to the point of the dependent variables.

Details

The actual estimation is done by translogEst.

Examples

Run this code

data( germanFarms )
   # quantity of crop outputs:
   germanFarms$qCrop <- germanFarms$vCrop / germanFarms$pOutput
   # quantity of animal outputs:
   germanFarms$qAnimal <- germanFarms$vAnimal / germanFarms$pOutput
   # quantity of variable inputs
   germanFarms$qVarInput <- germanFarms$vVarInput / germanFarms$pVarInput

   # estimate a translog ray production function
   estResult <- translogRayEst( yNames = c( "qCrop", "qAnimal" ),
      xNames = c( "qLabor", "land", "qVarInput" ),
      data = germanFarms )

   estResult

   summary( estResult )