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This paper presents some two-step estimators for a wide range of parametric panel data models with censored endogenous variables and sample selection bias. Our approach is to derive estimates of the unobserved heterogeneity responsible for the en-dogeneity/selection bias to include as additional explanatory variables in the primary equation. These are(More)
Any opinions expressed here are those of the author(s) and not those of the institute. Research disseminated by IZA may include views on policy, but the institute itself takes no institutional policy positions. The Institute for the Study of Labor (IZA) in Bonn is a local and virtual international research center and a place of communication between(More)
The closely related mitogen-activated protein kinase isoforms extracellular signal-regulated kinase 1 (ERK1) and ERK2 have been implicated in the control of cell proliferation, differentiation and survival. However, the specific in vivo functions of the two ERK isoforms remain to be analysed. Here, we show that disruption of the Erk2 locus leads to(More)
Any opinions expressed here are those of the author(s) and not those of the institute. Research disseminated by IZA may include views on policy, but the institute itself takes no institutional policy positions. The Institute for the Study of Labor (IZA) in Bonn is a local and virtual international research center and a place of communication between(More)
The anterior visceral endoderm plays a pivotal role in establishing anterior-posterior polarity of the mouse embryo, but the molecular nature of the signals required remains to be determined. Here, we demonstrate that Cerberus-like(-/-);Lefty1(-/-) compound mutants can develop a primitive streak ectopically in the embryo. This defect is not rescued in(More)
This paper provides a control function estimator to adjust for en-dogeneity in the triangular simultaneous equations model where there are no available exclusion restrictions to generate suitable instruments. Our approach is to exploit the dependence of the errors on exogenous variables (e.g. heteroscedasticity) to adjust the conventional control function(More)
H ousehold conditions and characteristics play an important role in determining the outcomes of children. The strength and nature of that role has been an important research area for social scientists. One characteristic is of special importance for economists—household incomes. Does having more money in the household produce better child outcomes over(More)
  • Ouarda Merrouche, Eliana La Ferrara, +5 authors Francis Vella
  • 2007
The International Campaign to Ban Landmines production and use estimates that there are more than 80 billion landmines in the ground in more than 80 countries. Despite the scale of the problem and large investments by OECD countries to clear mines in low income countries, the economic consequences of landmine contamination have been so far unexamined by(More)
This paper introduces bias-corrected estimators for nonlinear panel data models with both time invariant and time varying heterogeneity. These models include systems of equations with limited dependent variables and unobserved individual effects, and sample selection models with unobserved individual effects. Our two-step approach first estimates the(More)