Search results for "square"
showing 10 items of 1317 documents
Coefficient shifts in geographical ecology: an empirical evaluation of spatial and non-spatial regression
2009
12 páginas, 4 figuras, 3 tablas.
The Real Effects of Bank Branch Deregulation at Various Stages of Economic Development: The European Experience
2011
This paper provides evidence on the links between financial deregulation and economic performance in a European context. Specifically, we study the relaxation of bank branching restrictions in Spain which triggered off a remarkable inter-regional expansion of savings banks which was coincidental with an unprecedented period of sustained growth. Although related questions have been largely investigated for the US, the European experiences remain largely unexplored. An additional contribution is the use of quantile regression techniques which, unlike traditional OLS regression analysis, do not focus on the “average effect for the average province”. This change of focus helps to overcome the d…
BALANCED VARIABLE ADDITION IN LINEAR MODELS
2018
This paper studies what happens when we move from a short regression to a long regression in a setting where both regressions are subject to misspecification. In this setup, the least-squares estimator in the long regression may have larger inconsistency than the least-squares estimator in the short regression. We provide a simple interpretation for the comparison of the inconsistencies and study under which conditions the additional regressors in the long regression represent a “balanced addition” to the short regression.
Antecedentes y efectos del burnout-engagement del vendedor
2012
ResumenEl burnout o «síndrome del trabajador quemado» ha demostrado tener una gran importancia en el campo de las ventas. Sin embargo, no se han encontrado estudios que analicen en profundidad su opuesto, el engagement. El presente trabajo trata de profundizar en los antecedentes y efectos de un concepto integrador de ambos opuestos denominado burnout-engagement. Para ello, se realiza un estudio sobre 107 vendedores de distintos sectores. Los datos obtenidos, dado el tamaño de la muestra, son analizados mediante el sistema PLS. En lo relativo a antecedentes, los resultados demuestran una relación significativa entre el conflicto de rol y el burnout-engagement, la ambigüedad de rol y el burn…
WEIGHTED-AVERAGE LEAST SQUARES (WALS): A SURVEY
2014
Model averaging has become a popular method of estimation, following increasing evidence that model selection and estimation should be treated as one joint procedure. Weighted- average least squares (WALS) is a recent model-average approach, which takes an intermediate position between frequentist and Bayesian methods, allows a credible treatment of ignorance, and is extremely fast to compute. We review the theory of WALS and discuss extensions and applications.
Sampling properties of the Bayesian posterior mean with an application to WALS estimation
2022
Many statistical and econometric learning methods rely on Bayesian ideas, often applied or reinterpreted in a frequentist setting. Two leading examples are shrinkage estimators and model averaging estimators, such as weighted-average least squares (WALS). In many instances, the accuracy of these learning methods in repeated samples is assessed using the variance of the posterior distribution of the parameters of interest given the data. This may be permissible when the sample size is large because, under the conditions of the Bernstein--von Mises theorem, the posterior variance agrees asymptotically with the frequentist variance. In finite samples, however, things are less clear. In this pa…
Determinants of COVID-19 Vaccine Rollouts and Their Effects on Health Outcomes
2022
Background Vaccination against the coronavirus disease (SARS-CoV-2) is understood to be the key way out of the COVID-19 pandemic. Limited evidence exists on the determinants of vaccine rollouts and their health effects at the country level. Objective Examine the determinants of COVID-19 vaccine rollouts and their effects on health outcomes. Methods Ordinary least squares regressions with standard errors clustered at the country level for Cross-section and Panel daily data of vaccinations and various health outcomes (new COVID-19 cases, fatalities, intensive care unit (ICU) admissions) for an unbalanced sample of about 200 countries during the period 16 December 2020 to 20 June 2021. Results…
Molecular origin and hydration dependence of protein anharmonicity: an elastic neutron scattering study.
2010
Two main onsets of anharmonicity are present in protein dynamics. Neutron scattering on protein hydrated powders revealed a first onset at about 150 K and a second one at about 230 K (the so called dynamical transition). In order to assess the molecular origin of protein anharmonicity, we study different homomeric polypeptides by incoherent elastic neutron scattering, thus disentangling the contribution of different molecular groups in proteins. We show that methyl group rotations are the main contributors to the low temperature onset. Concerning the dynamical transition, we show that it also occurs in absence of side chains; however, the presence and mobility of side chains substantially i…
Electric relaxation and Mn3+/Mn4+ charge transfer in Fe-doped Bi12MnO20–BiMn2O5 structural self-composite
2016
Fe-doped Bi12MnO20–BiMn2O5 ceramics was sintered at 1130 K for 6 h in ambient air. Two centro-symmetric phases formed thermodynamically stable self-composite material that was deduced from X-ray pattern analysis. The lattice parameters were a = 10.147(8) Å—for the cubic I23 Bi12MnO20 phase; and a = 7.545(4) Å, b = 8.538(1) Å, c = 5.758(3) Å—for the orthorhombic Pbam BiMn2O5 phase. The 57Fe Mössbauer spectrum, recorded at room temperature, has shown pure electronic quadrupolar split. The major doublets reflected the occurrence of Fe3+ ions distributed in two sites, i.e., octahedral Fe4+O6 and square pyramidal Fe3+O5, with preferential occupation of the pyramidal sites, that was consistent wi…
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…