gmnl (version 1.1-3.2)

wtp.gmnl: Compute Willingness-to-pay

Description

Compute the willingness-to-pay.

Usage

wtp.gmnl(object, wrt = NULL, digits = max(3, getOption("digits") - 2))

Arguments

object

an object of class gmnl.

wrt

a string indicating the variable with respect to which the WTP is computed,

digits

number of significant digits to be used for most numbers.

Value

A coefficient matrix with the WTP point estimates and standard errors.

Details

For each coefficient, this function computes both the point estimate and standard error of WTP with respect to the variable specified in the argument wrt. Specifically, let \(\beta_k\) be the coefficient for variable \(k\), then $$WTP_{k}=-\beta_k/\beta_p$$

where \(\beta_p\) is the coefficient for the variable specified with the argument wrt. Note that, wtp.gmnl does not include the negative sign.

wtp.gmnl function is a wrapper for the deltamethod function of the msm package.

References

• Greene, W. H. (2012). Econometric Analysis, Seventh Edition. Pearson Hall.

• Train, K. (2009). Discrete Choice Methods with Simulation. Cambridge University Press.

See Also

deltamethod for the estimation of the standard errors.

Examples

# NOT RUN {
## Examples using the Electricity data set from the mlogit package
library(mlogit)
data("Electricity", package = "mlogit")
Electr <- mlogit.data(Electricity, id.var = "id", choice = "choice",
                     varying = 3:26, shape = "wide", sep = "")
                     
## Estimate a conditional logit model
clogit <- gmnl(choice ~ pf + cl + loc + wk + tod + seas| 0,
               data = Electr)
wtp.gmnl(clogit, wrt = "pf")
# }