BACKGROUND The objective of this study was to demonstrate the use of the Heckman two-step method to assess and correct for bias due to missing health related quality of life (HRQL) surveys in a clinical study of acute coronary syndrome (ACS) patients. METHODS We analyzed data from 2,733 veterans with a confirmed diagnosis of acute coronary syndromes (ACS), including either acute myocardial in...

On the Identification of Frisch Labor Supplies This paper examines how Frisch labor supplies, and other structural components of the intertemporal model of labor supply, can be recovered from estimates obtained with the approach developed by Heckman and MaCurdy. JEL Classification: J22

As a coastal emerging country, export-led marine economy has been the development model of Vietnam over past decades since The Renovation 1986. Given rise globalization, regional economic integration and logistics enhancement have identified as key engines for sustainability by Vietnamese government. Nevertheless, little sectoral sub-sectoral evidence given platform shaped policies relevant to ...

Following Boalch-Yamakawa and Meinrenken, we consider a certain class of moduli spaces on bordered surfaces from quasi-Hamiltonian perspective. For given Lie group $G$, these character varieties parametrize flat $G$-connections "twisted" local systems, in the sense that transition functions take values $G\rtimes\mathrm{Aut}(G)$. After reviewing necessary tools to discuss twisted manifolds, cons...

We present an explicit product formula for the spherical functions of the compact Gelfand pairs (G,K1) = (SU(p+ q), SU(p)× SU(q)) with p ≥ 2q, which can be considered as the elementary spherical functions of one-dimensional K-type for the Hermitian symmetric spaces G/K with K = S(U(p)× U(q)). Due to results of Heckman, they can be expressed in terms of Heckman-Opdam Jacobi polynomials of type B...

This introduction to the R package sampleSelection is a slightly modified version of Toomet and Henningsen (2008b), published in the Journal of Statistical Software. This paper describes the implementation of Heckman-type sample selection models in R. We discuss the sample selection problem as well as the Heckman solution to it, and argue that although modern econometrics has nonand semiparamet...

This paper derives conditions under which preferences and technology are nonparametrically identified in hedonic equilibrium models, where products are differentiated along more than one dimension and agents are characterized by several dimensions of unobserved heterogeneity. With products differentiated along a quality index and agents characterized by scalar unobserved heterogeneity, single c...

Section 5.2 of this book decries the decline in the understanding of structural equation modeling in econometric in the past three decades (see also Hoover 2003, “Lost Causes”) and attributes this decline to a careless choice of notation which blurred the essential distinction between algebraic and structural equations. In a series of articles (Heckman 2000, 2003, 2005; Heckman and Vytlacil 200...