twostep {ssmodels}R Documentation

Two-Step Estimation of the Classic Heckman Model

Description

Estimates the parameters of the classical Heckman sample selection model using the two-step procedure.

Usage

twostep(selection, outcome, data = sys.frame(sys.parent()))

Arguments

selection

A formula for the selection equation.

outcome

A formula for the outcome equation.

data

A data frame containing the variables.

Details

The two-step method first estimates a Probit model for the selection equation, then fits an outcome equation that includes the Inverse Mills Ratio (IMR) as an additional regressor to correct for sample selection bias.

Value

A numeric vector containing:

References

There are no references for Rd macro ⁠\insertAllCites⁠ on this help page. For details, see Heckman (1979).

Examples

data(MEPS2001)
attach(MEPS2001)
selectEq <- dambexp ~ age + female + educ + blhisp + totchr + ins + income
outcomeEq <- lnambx ~ age + female + educ + blhisp + totchr + ins
twostep(selectEq, outcomeEq, data = MEPS2001)


[Package ssmodels version 2.0.1 Index]