snqProfitWeights {micEcon} | R Documentation |
Returns a vector of weights to normalize prices on a Symmetric Normalized Quadratic (SNQ) Profit function.
snqProfitWeights( priceNames, quantNames, data, method = "DW92", base = 1 )
priceNames |
a vector of strings containing the names of netput prices. |
quantNames |
a vector of strings containing the names of netput quantities. |
data |
a data frame containing the data. |
method |
the method to determine the weights (see details). |
base |
the base period(s) for scaling prices (see details). |
If argument method
is 'DW92' the method of Diewert and
Wales (1992) is applied. They predetermine the weights by
theta_{i} = frac{ displaystyle <=ft | overline{x}_{i} right| p_{i}^{0} }{ displaystyle sum_{i=1}^{n} <=ft| overline{x}_{i} right| p_{i}^{0}}
Defining the scaled netput quantities as widetilde{x}_{i}^{t} & = & x_{i}^{t}cdot p_{i}^{0} we get following formula:
theta_{i} = frac{ displaystyle <=ft| overline{ widetilde{ x } }_{i} right|}{ displaystyle sum_{i=1}^{n} <=ft| overline{ widetilde{ x } }_{i} right|}
The prices are scaled that they are unity in the base period or - if there
is more than one base period - that the
means of the prices over the base periods are unity.
The argument base
can be either
(a) a single number: the row number of the base prices,
(b) a vector indicating several observations: The means of these
observations are used as base prices,
(c) a logical vector with the same length as the data
: The
means of the observations indicated as 'TRUE' are used as base prices, or
(d) NULL
: prices are not scaled.
Arne Henningsen
data( germanFarms ) germanFarms$qOutput <- germanFarms$vOutput / germanFarms$pOutput germanFarms$qVarInput <- -germanFarms$vVarInput / germanFarms$pVarInput germanFarms$qLabor <- -germanFarms$qLabor priceNames <- c( "pOutput", "pVarInput", "pLabor" ) quantNames <- c( "qOutput", "qVarInput", "qLabor" ) snqProfitWeights( priceNames, quantNames, germanFarms )