Search results for " Root"
showing 10 items of 627 documents
Is the environmental performance of industrialized countries converging? A ‘SURE’ approach to testing for convergence
2008
In this paper, we test for convergence in the environmental performance of a sample of OECD countries, with data ranging from 1971 to 2002. First, we use Data Envelopment Analysis (DEA) to compute two environmental performance indicators (EPIs) in the production theory framework. Second, we propose the use of a sequential multivariate approach to test for convergence in environmental performance. These tests allow us to reconcile the time series literature with the cross-sectional dimension, which is basic when testing for convergence in regional blocs. The SURE technique is used, which allows for the existence of correlations across the series without imposing a common speed of mean revers…
Hysteresis vs. natural rate of unemployment: new evidence for OECD countries
2004
Abstract The paper tests hysteresis effects in unemployment using panel data for 19 OECD countries. We apply a sequential procedure based in two multivariate augmented Dickey-Fuller test (ADF)-type panel unit root tests in a SURE framework. We strongly reject the joint null of hysteresis and find that only seven countries present evidence of hysteresis.
Testing the stationarity of interest rates using a SUR approach
1998
Abstract Using data on average yields to maturity of German bonds with different time to maturity it is shown that the time series contain a unit root if the standard augmented Dickey–Fuller test is applied separately to each series. To improve the power of the test we carried out a recently developed approach, estimating the regressions for each time to maturity jointly using a seemingly unrelated regressions approach.
50 years of capital mobility in the eurozone: breaking the Feldstein-Horioka puzzle
2021
AbstractThis paper assesses capital mobility for the Eurozone countries by studying the long-run relationship between domestic investment and savings for the period 1970-2019. Our main goal is to analyze the impact of economic events on capital mobility during this period. We apply the cointegration methodology in a setting that allows us to identify endogenous breaks in the long-run saving-investment relationship. Precisely, the breaks coincide with relevant economic events. We find a downward trend in the saving-investment retention since the 70s for the so-called “core countries”, whereas this trend is not so evident in the peripheral, where the financial and sovereign crises have had a …
TESTING FOR REAL INTEREST RATE PARITY USING PANEL STATIONARITY TESTS WITH DEPENDENCE: A NOTE*
2009
In this paper we test for real interest parity (RIRP) among the 19 major OECD countries over the period 1978:Q1–2006:Q1 using both short- and long-run definitions of interest rates. Once the independence hypothesis is rejected among these series, we test for RIRP using panel data unit root and stationarity tests based on common factor models that allow for pervasive forms of dependence. Our results indicate that there is no evidence in favor of the weak version of the RIRP since one of the common factors that have been estimated is non-stationary.
Estimating additional root cohesion by exploiting a root topological model based on Leonardo’s Rule
2020
Root topological models are schematic representations of the root structure based on a defined topology graph theory. In the context of hillslope stabilization modeling against rainfall-induced shallow landslides, the root topological models may be used in combination with root strength models assessment, such as the Root Bundle Model (RBM), to estimate the ultimate root reinforcement. The effect of plant roots on slope stabilization is determined by the interaction between soil and the hydrological processes (within the root zone) and the biotechnical characteristics of the root system, such as root length, root density, root tensile strength, root area, root diameter profile and the total…
A new mathematical function for describing electrophoretic peaks.
2005
A new model is proposed for characterizing skewed electrophoretic peaks, which is a combination of leading and trailing edge functions, empirically modified to get a rapid recovery of the baseline. The peak model is a sum of square roots and is called thereby "combined square roots (CSR) model". The flexibility of the model was checked on theoretical and experimental peaks with asymmetries in the range of 0-10 (expressed as the ratio of the distance between the center and the trailing edge, and the center and the leading edge of the chromatographic peak, measured at 10% of peak height). Excellent fits were found in all cases. The new model was compared with other three models that have show…
Clinical evaluation of the Er:YAG laser in combination with an enamel matrix protein derivative for the treatment of intrabony periodontal defects: a…
2003
OBJECTIVES The aim of the present study was to compare the combination therapy of deep intrabony periodontal defects using an Er:YAG laser (ERL) and enamel matrix protein derivative (EMD) to scaling and root planing+ ethylenediaminetetraacetic acid (EDTA)+EMD. MATERIAL AND METHODS Twenty-two patients with chronic periodontitis, each of whom displayed 1 intrabony defect, were randomly treated with access flap surgery and defect debridement with an Er:YAG (160 mJ/pulse, 10 Hz) plus EMD (test) or with access flap surgery followed by scaling and root planing (SRP) with hand instruments plus EDTA and EMD (control). The following clinical parameters were recorded at baseline and at 6 months: plaq…
Energy use–GDP deterministic cointegration: progress towards EU-15 Kyoto targets
2015
This article examines whether the energy consumption–GDP relationship is in long-term equilibrium for EU-15 countries. Unlike many previous works, we apply a nonlinear unit root test introduced by Kapetanios et al. (2003a) and extended by Chong et al. (2008) that identifies not only deterministic cointegration, but also the stronger concept of stochastic cointegration. The results yield a clear pattern: Austria, Denmark, Italy, the Netherlands, Portugal and Spain must achieve greater emissions reductions between 2009 and 2012 to reach their respective Kyoto targets.
Dental anatomy portrayed with microscopic volume investigations
1993
The clinical treatment of the root canal of teeth--called endodontics--assumes a precise idea of the spatial arrangement of the anatomy of teeth and their inner structure. By using computer-assisted data acquisition from filmed sequences of histologic serial sections and a special kind of magnetic resonance microscope--the Stray Field Imaging (STRAFI)--volume investigations were carried out using special functions of a newly developed 3D software. Possible applications and future perspectives are discussed.