A Nonlinear Panel Data Model of Cross-Sectional Dependence

This paper proposes a nonlinear panel data model which can generate endogenously both `weak' and `strong' cross-sectional dependence. The model's distinguishing characteristic is that a given agent's behaviour is influenced by an aggregation of the views or actions of those around them. The model allows for considerable flexibility in terms of the genesis of this herding or clustering type behaviour. At an econometric level, the model is shown to nest various extant dynamic panel data models. These include panel AR models, spatial models, which accommodate weak dependence only, and panel models where cross-sectional averages or factors exogenously generate strong, but not weak, cross sectional dependence. An important implication is that the appropriate model for the aggregate series becomes intrinsically nonlinear, due to the clustering behaviour, and thus requires the disaggregates to be simultaneously considered with the aggregate. We provide the associated asymptotic theory for estimation and inference. This is supplemented with Monte Carlo studies and two empirical applications which indicate the utility of our proposed model as both a structural and reduced form vehicle to model different types of cross-sectional dependence, including evolving clusters.Nonlinear Panel Data Model; Clustering; Cross-section Dependence; Factor Models; Monte Carlo Simulations; Application to Stock Returns and Inflation Expectations

A Nonlinear Panel Model of Cross-sectional Dependence

This paper proposes a new panel model of cross-sectional dependence. The model has a number of potential structural interpretations that relate to economic phenomena such as herding in financial markets. On an econometric level it provides a flexible approach to the modelling of interactions across panel units and can generate endogenous cross-sectional dependence that can resemble such dependence arising in a variety of existing models such as factor or spatial models. We discuss the theoretical properties of the model and ways in which inference can be carried out. We supplement this analysis with a detailed Monte Carlo study and two empirical illustrations.Cross-sectional dependence, Nonlinearity, Factor models, Panel models, Fixed effects

An initial approach to the utilization of VAS satellite sounding data

The primary objective is the development of methods to utilize satellite soundings. To achieve that, a more precise understanding of the characteristics of satellite derived soundings is required. The initial approach in the utilization of satellite soundings is to find a way to combine rawinsondes and satellite data into a unified data set. If this can be done in a meaningful way, satellite data could be integrated into existing data and interpretation would be enhanced. In this attempt, both rawinsonde and satellite soundings will be decomposed by the use of the Fourier cosine series. Then, each harmonic will be compared to get a better understanding of the representativeness of the satellite sounding data. Harmonics taken from satellite and rawinsonde soundings will be combined to provide a unified data set that can be used both over data sparse ocean areas as well as over land where rawinsonde data are available

Value Discount of Business Groups Surrounding the Asia Financial Crisis: Evidence from Korean Chaebols

Asian Financial Crisis, Business Group, Chaebol, Diversification, Firm Value

Stereochemical assignment of the protein-protein interaction inhibitor JBIR-22 by total synthesis

The authors acknowledge the EPSRC and Cancer Research UK (CRUK Grant No. C21383/A6950) for funding this research.Recent reports have highlighted the biological activity associated with a sub-family of the tetramic acid class of natural products. Despite the fact that members of this sub-family act as protein-protein interaction inhibitors of relevance to proteasome assembly, no synthetic work has been reported. This may be because this sub-family contains an unnatural 4,4-disubstitued glutamic acid, the synthesis of which provides a key challenge. Here we describe a highly stereoselective route to a masked form of this unnatural amino acid. This enabled the synthesis of two of the possible diastereomers of JBIR-22 and allowed its relative and absolute stereochemistry to be assigned.Publisher PDFPeer reviewe

Ab initio no-core solutions for 6^6Li

We solve for properties of $^6$Li in the ab initio No-Core Full Configuration approach and we separately solve for its ground state and $J^{\pi}=2_{2}^{+}$ resonance with the Gamow Shell Model in the Berggren basis. We employ both the JISP16 and chiral NNLO$_{opt}$ realistic nucleon-nucleon interactions and investigate the ground state energy, excitation energies, point proton root-mean-square radius and a suite of electroweak observables. We also extend and test methods to extrapolate the ground state energy, point proton root-mean-square radius, and electric quadrupole moment. We attain improved estimates of these observables in the No-Core Full Configuration approach by using basis spaces up through N$_{max}$=18 that enable more definitive comparisons with experiment. Using the Density Matrix Renormalization Group approach with the JISP16 interaction, we find that we can significantly improve the convergence of the Gamow Shell Model treatment of the $^6$Li ground state and $J^{\pi}=2_{2}^{+}$ resonance by adopting a natural orbital single-particle basis.Comment: 25 pages, 18 figure

A robotics platform for automated batch fabrication of high density, microfluidics-based DNA microarrays, with applications to single cell, multiplex assays of secreted proteins

Microfluidics flow-patterning has been utilized for the construction of chip-scale miniaturized DNA and protein barcode arrays. Such arrays have been used for specific clinical and fundamental investigations in which many proteins are assayed from single cells or other small sample sizes. However, flow-patterned arrays are hand-prepared, and so are impractical for broad applications. We describe an integrated robotics/microfluidics platform for the automated preparation of such arrays, and we apply it to the batch fabrication of up to eighteen chips of flow-patterned DNA barcodes. The resulting substrates are comparable in quality with hand-made arrays and exhibit excellent substrate-to-substrate consistency. We demonstrate the utility and reproducibility of robotics-patterned barcodes by utilizing two flow-patterned chips for highly parallel assays of a panel of secreted proteins from single macrophage cells

Impact of BovineSomatotropin (BST) on Dairy Produce

The use of bovine somatotropin (BST) in dairy herds has been shown to increase productivity levels. Bovine somatotropin is a biotechnology that, when injected in dairy cows, results in increased milk production levels anywhere from 10 to 40 percent (Kalter, et al.). Presently the injections are daily and have been shown to have a rather quick and dramatic increase in production levels