translogHessian function

Hessian matrix of a translog function

Calculate the Hessian matrices of a translog function.

translogHessian( xNames, data, coef, yName = NULL,
   dataLogged = FALSE, bordered = FALSE )

Arguments

• xNames: a vector of strings containing the names of the independent variables.
• data: dataframe containing the data.
• coef: vector containing all coefficients.
• yName: an optional string containing the name of the dependent variable. If it is NULL, the dependent variable is calculated from the independent variables and the coefficients.
• dataLogged: logical. Are the values in data already logged?
• bordered: logical. Should the bordered Hessians be returned?

Returns

a list containing following the (bordered) Hessian matrices at each data point.

See Also

translogEst, translogDeriv and translogCalc

Author(s)

Arne Henningsen

Examples

data( germanFarms )
   # output quantity:
   germanFarms$qOutput <- germanFarms$vOutput / germanFarms$pOutput
   # quantity of variable inputs
   germanFarms$qVarInput <- germanFarms$vVarInput / germanFarms$pVarInput
   # a time trend to account for technical progress:
   germanFarms$time <- c(1:20)

   # estimate a quadratic production function
   estResult <- translogEst( "qOutput", c( "qLabor", "land", "qVarInput", "time" ),
      germanFarms )

   # compute the Hessian matrices (with "fitted" output)
   hessians <- translogHessian( c( "qLabor", "land", "qVarInput", "time" ),
      germanFarms, coef( estResult ) )
   hessians[[ 1 ]]

   # compute the Hessian matrices (with observed output)
   hessiansObs <- translogHessian( c( "qLabor", "land", "qVarInput", "time" ),
      germanFarms, coef( estResult ), "qOutput" )
   hessiansObs[[ 1 ]]

   # compute the bordered Hessian matrices
   borderedHessians <- translogHessian( c( "qLabor", "land", "qVarInput", "time" ),
      germanFarms, coef( estResult ), bordered = TRUE )
   borderedHessians[[ 1 ]]