|
- Sample selection versus two-part models revisited: The case of female . . .
The sample selection model was first introduced by Heckman, 1976, Heckman, 1979 and its main application was in the context of wage equation estimation (for a general discussion of the sample selection model see Puhani, 2000) In such applications we are often interested in the effect of a variable such as schooling on the wage
- Semiparametric Estimation with Data Missing Not at Random Using an . . .
Estimation using Heckman-type selection models may be sensitive to these parametric assumptions (Winship and Mare, 1992; Puhani, 2000), although there has been signi cant work towards relaxing some of the as-sumptions (Manski, 1985; Newey et al , 1990; Das et al , 2003; Newey, 2009)
- Grandparental availability for child care and maternal labor force . . .
Although the model is formally identified even without an exclusion restriction (Puhani 2000), we propose an economic identification that uses as “instrument” a proxy for the woman’s spouse being an only child; that is, the number (from the SHIW) of noncohabiting siblings still alive for each individual in a couple
- A Micro-perspective Analysis of the Demand for Greek and Non-Greek . . .
The exclusion restriction in the Heckman model states that there must be at least one variable which appears with a non-zero coefficient in the selection (probit) equation but does not appear in the conditional demand equation (Puhani, 2000)
- Using Instruments for Selection to Adjust for Selection Bias in . . .
The exclusion restriction assumption effectively requires the instrument to be independent of any variable for which data are missing In an MR study with missing data only for the exposure, 𝑍 Z italic_Z must be independent of the exposure (conditional on the genetic instrument 𝐺 G italic_G for inference) in order to adjust for selection
- Explaining travel distance during same-day visits - ScienceDirect
For a detailed discussion on the interpretation of the estimated coefficients of the Heckman model we refer to Puhani (2000) When examining the results, we notice that age plays both a roll on the probability to go on a same-day visit and on distance travelled The square term indicates a concave (i e inverted U-shaped) relationship
- Cloud technologies, firm growth and industry concentration: Evidence . . .
This variable must adhere to two conditions (Puhani 2000), similarly to the standard IV conditions of 2SLS: it must strongly predict the endogenous dummy variable (i e , exhibit relevance) and must be exogenous (i e , satisfy the exclusion restriction) in the presence of other controls
- Heckman correction - Wikipedia
The Heckman correction is a statistical technique to correct bias from non-randomly selected samples or otherwise incidentally truncated dependent variables, a pervasive issue in quantitative social sciences when using observational data [1] Conceptually, this is achieved by explicitly modelling the individual sampling probability of each observation (the so-called selection equation
|
|
|