OBJECTIVES Protest responses, whereby respondents refuse to state the value they place on the health gain, are commonly encountered in contingent valuation (CV) studies, and they tend to be excluded from analyses. Such an approach will be biased if protesters differ from non-protesters on characteristics that predict their responses. The Heckman selection model has been commonly used to adjust ...

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...

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...

Abstract This paper aims to identify neighborhood institutional resources (e.g., nonprofit organizations, libraries, and labor market conditions) that promote Mexican‐origin high school students' progress in the science, technology, engineering, mathematics (STEM) pathway into postsecondary education. A nationally representative, longitudinal sample of 1340 students from Educational Longitudina...

The asymptotics of characters $\chi_{k\lambda}(\exp(h/k))$ irreducible representations a compact Lie group $G$ for large values the scaling factor $k$ are given by Duistermaat-Heckman (DH) integrals over coadjoint orbits $G$. This phenomenon generalises to central extensions loop groups $\widehat{LG}$ and diffeomorphisms circle $\widehat{\rm Diff}(S^1)$. We show that integrable modules affine K...

OBJECTIVE The aim was to examine whether design features of Wave 1, 1980 National Incidence Study (NIS) data resulted in sample selection bias when certain victims of maltreatment were excluded. METHOD Logistic regression models for the probability of child abuse reports to the child protective services (CPS) were estimated using maximum likelihood methods for Black (n = 511) and White (n = 2...