Nonlinear Impulse Response Functions and Local Projections

The goal of this paper is to extend the method of estimating Impluse Response Functions (IRFs) by means of Local Projection (LP) in a nonlinear dynamic framework. We discuss the existence of a nonlinear autoregressive representation for a Markov process, and explain how their Impulse Response Functions are directly linked to the nonlinear Local Projection, as in the case for the linear setting. We then present a nonparametric LP estimator, and compare its asymptotic properties to that of IRFs obtained through direct estimation. We also explore issues of identification for the nonlinear IRF in the multivariate framework, which remarkably differs in comparison to the Gaussian linear case. In particular, we show that identification is conditional on the uniqueness of deconvolution. Then, we consider IRF and LP in augmented Markov models.Comment: 44 pages, 4 figure

Theoretical Engineering and Satellite Comlink of a PTVD-SHAM System

This paper focuses on super helical memory system's design, 'Engineering, Architectural and Satellite Communications' as a theoretical approach of an invention-model to 'store time-data'. The current release entails three concepts: 1- an in-depth theoretical physics engineering of the chip including its, 2- architectural concept based on VLSI methods, and 3- the time-data versus data-time algorithm. The 'Parallel Time Varying & Data Super-helical Access Memory' (PTVD-SHAM), possesses a waterfall effect in its architecture dealing with the process of voltage output-switch into diverse logic and quantum states described as 'Boolean logic & image-logic', respectively. Quantum dot computational methods are explained by utilizing coiled carbon nanotubes (CCNTs) and CNT field effect transistors (CNFETs) in the chip's architecture. Quantum confinement, categorized quantum well substrate, and B-field flux involvements are discussed in theory. Multi-access of coherent sequences of 'qubit addressing' in any magnitude, gained as pre-defined, here e.g., the 'big O notation' asymptotically confined into singularity while possessing a magnitude of 'infinity' for the orientation of array displacement. Gaussian curvature of k(k<0) is debated in aim of specifying the 2D electron gas characteristics, data storage system for defining short and long time cycles for different CCNT diameters where space-time continuum is folded by chance for the particle. Precise pre/post data timing for, e.g., seismic waves before earthquake mantle-reach event occurrence, including time varying self-clocking devices in diverse geographic locations for radar systems is illustrated in the Subsections of the paper. The theoretical fabrication process, electromigration between chip's components is discussed as well.Comment: 50 pages, 10 figures (3 multi-figures), 2 tables. v.1: 1 postulate entailing hypothetical ideas, design and model on future technological advances of PTVD-SHAM. The results of the previous paper [arXiv:0707.1151v6], are extended in order to prove some introductory conjectures in theoretical engineering advanced to architectural analysi

Change-point Problem and Regression: An Annotated Bibliography

The problems of identifying changes at unknown times and of estimating the location of changes in stochastic processes are referred to as the change-point problem or, in the Eastern literature, as disorder . The change-point problem, first introduced in the quality control context, has since developed into a fundamental problem in the areas of statistical control theory, stationarity of a stochastic process, estimation of the current position of a time series, testing and estimation of change in the patterns of a regression model, and most recently in the comparison and matching of DNA sequences in microarray data analysis. Numerous methodological approaches have been implemented in examining change-point models. Maximum-likelihood estimation, Bayesian estimation, isotonic regression, piecewise regression, quasi-likelihood and non-parametric regression are among the methods which have been applied to resolving challenges in change-point problems. Grid-searching approaches have also been used to examine the change-point problem. Statistical analysis of change-point problems depends on the method of data collection. If the data collection is ongoing until some random time, then the appropriate statistical procedure is called sequential. If, however, a large finite set of data is collected with the purpose of determining if at least one change-point occurred, then this may be referred to as non-sequential. Not surprisingly, both the former and the latter have a rich literature with much of the earlier work focusing on sequential methods inspired by applications in quality control for industrial processes. In the regression literature, the change-point model is also referred to as two- or multiple-phase regression, switching regression, segmented regression, two-stage least squares (Shaban, 1980), or broken-line regression. The area of the change-point problem has been the subject of intensive research in the past half-century. The subject has evolved considerably and found applications in many different areas. It seems rather impossible to summarize all of the research carried out over the past 50 years on the change-point problem. We have therefore confined ourselves to those articles on change-point problems which pertain to regression. The important branch of sequential procedures in change-point problems has been left out entirely. We refer the readers to the seminal review papers by Lai (1995, 2001). The so called structural change models, which occupy a considerable portion of the research in the area of change-point, particularly among econometricians, have not been fully considered. We refer the reader to Perron (2005) for an updated review in this area. Articles on change-point in time series are considered only if the methodologies presented in the paper pertain to regression analysis

Prices, delay and the dynamics of trade.

We characterize trading patterns and their dynamics in a market in which trade is bilateral, finding a trading partner is costly, prices are determined by bargaining, and preferences are private information. We also determine how the trading pattern depends on the market composition. Our analysis reveals that market equilibria may be inefficient and may exhibit delay. As the market becomes frictionless the welfare loss due to inefficiency vanishes; delay persists, however, and in this respect frictionless markets are not competitive.Trade dynamics; Matching; Bargaining; Delay; Asymmetric information; Decentralized trade;

Three implications of learning behaviour for price processes.

no abstract availableConsumers' preferences; Economics -- Psychological aspects;

Diffusion MRI and Pharmacological Enhancement of Motor Recovery after Stroke

The primary goal of these studies is to enhance recovery of motor function following stroke and to understand the relationship between dMRI measures and the cellular, functional, and behavioral changes acutely and chronically following rehabilitation. We hypothesize that dMRI will be a sensitive tool to identify microstructural changes acutely and chronically following stroke and that promoting mitochondria biogenesis will lead to better functional recovery and induce structural and functional plasticity following rehabilitative training. Towards this goal, we used a combination of sensitive behavioral, immunohistochemical and mitochondrial-related molecular markers, and diffusion magnetic resonance imaging (dMRI) to investigate the time course of acute and chronic stroke effects. We were able to detect acute changes in dMRI metrics and correlate those changes with functional and morphological plasticity following stroke. Our work has shown that mean kurtosis, a dMRI metric, increased acutely after stroke and persists days poststroke in the lesion core. We found strong correlations between mean diffusivity and astrogliosis in the perilesional stroke area. There were no correlations between dendritic and axonal surface densities and dMRI metrics acutely following stroke. However, behavioral-induced and learning-induced neural plasticity was not detected with dMRI changes chronically in perilesional grey matter or white matter. Our studies have revealed mitochondria dysfunction that persists for at least six days post stroke in ipsilesional cortex and striatum following a focal sensorimotor (SMC) ischemic lesion. Therefore, we proposed that pharmacologically enhancing mitochondria function and biogenesis would promote recovery after stroke when administered early after stroke. We found that giving a drug known to induce mitochondria biogenesis, formoterol, a FDA approved long-lasting β2-adrenergic receptor agonist, twenty-four hours after SMC ischemic lesions caused a full restoration of markers of mitochondria function in the striatum three days post stroke and stimulates a partial recovery of functional markers in the cortex six days post-stroke. Our studies revealed that animals given formoterol (0.1mg/kg) combined with motor rehabilitative training (RT) daily for 15 days leads to better recovery of motor function than animals given vehicle treatment and RT. These data demonstrate that stimulating mitochondria biogenesis acutely after stroke enhances functional motor recovery

Celebrated Econometricians: Katarina Juselius and Søren Johansen

This Special Issue collects contributions related to advances in the theory and practice of Econometrics induced by the research of Katarina Juselius and Søren Johansen, whom this Special Issue aims to celebrate. The papers in this Special Issue provide advances on several topics, and they are grouped in the following areas, with three to four papers per group). The first group provides a historical perspective on Katarina’s and Søren’s contributions to Econometrics. The second group of papers concentrates on representation theory, while the third focuses on estimation and inference. The fourth group explores extensions of CVARs for modelling and forecasting, and the fifth and final group is centered on empirical applications