micEcon (version 0.5-6)

quadFuncEst: Estimate a quadratic function

Description

Estimate a quadratic function.

Usage

quadFuncEst( yName, xNames, data, quadHalf = TRUE, exVarScale = 1 )

Arguments

yName

a vector of strings containing the name of the dependent variable.

xNames

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

data

dataframe containing the data.

quadHalf

logical. Multiply the quadratic terms by one half?

exVarScale

a scalar or vector with length equal to nrow( data ). All exogenous variables (including the quadratic terms) are divided by this value/these values.

Value

• a list of class quadFuncEst containing following objects:
• lm
  a list returned by lm.
• residuals
  residuals.
• fitted
  fitted values.
• coef
  vector of all coefficients.
• coefCov
  covariance matrix of all coefficients.
• r2
  $R^2$ value.
• r2bar
  adjusted $R^2$ value.
• nObs
  number of observations.
• model.matrix
  the model matrix.

See Also

quadFuncCalc, quadFuncDeriv, translogEst and snqProfitEst.

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 <- quadFuncEst( "qOutput", c( "qLabor", "land", "qVarInput", "time" ),
      germanFarms )

   coef( estResult )
   estResult$r2