ESTIMATING NON-PARAMETRIC AND PARAMETRIC TRANSFORMATION FUNCTIONS FROM SURVEY DATA: AN APPLICATION OF MINIMUM CROSS-ENTROPY

A model of a (convex) technology of representative and non-representative firms in a heterogeneous sector is presented in non-parametric and parametric versions. The heterogeneity is specified with error terms. The models including a non-parametric distribution of the errors can be estimated with entropy econometrics from firm survey data. This requires two important modifications in the standard approach to entropy estimation of Golan, Judge and Miller: The compact support of the probability distribution should be designed to capture eventual non-zero covariance. And cross-entropy need to be redefined for cases of multiple observations.Research Methods/ Statistical Methods,

Adsorption of Methanol on Aluminum Oxide: A Density Functional Study

Theoretical calculations based on density functional theory have made significant contributions to our understanding of metal oxides, their surfaces, and the binding of molecules at these surfaces. In this paper we investigate the binding of methanol at the alpha-Al2O3(0001) surface using first-principles density functional theory. We calculate the molecular adsorption energy of methanol to be E^g_ads=1.03 eV/molecule. Taking the methanol-methanol interaction into account, we obtain the adsorption energy E_ads=1.01 eV/molecule. Our calculations indicate that methanol adsorbs chemically by donating electron charge from the methanol oxygen to the surface aluminum. We find that the surface atomic structure changes upon adsorption, most notably the spacing between the outermost Al and O layers changes from 0.11 Angstrom to 0.33 Angstrom.Comment: 11 pages, 3 figures, 1 tabl

FRW Universe Models in Conformally Flat Spacetime Coordinates. I: General Formalism

The 3-space of a universe model is defined at a certain simultaneity. Hence space depends on which time is used. We find a general formula generating all known and also some new transformations to conformally flat spacetime coordinates. A general formula for the recession velocity is deduced.Comment: 12 page

Bianchi Type-I Universe Models with Nonlinear Viscosity

In this paper we study the evolution of spatially homogeneous and anisotropic Bianchi type-I Universe models with the cosmological constant, \Lambda, and filled with nonlinear viscous fluid. The dynamical equations for these models are obtained and solved for some special cases. We calculate the statefinder parameters for the models and display them in the s-r-plane