Search Results - "Fraga, M. Isabel"

Qualitative and quantitative analysis of carrageenan content in gametophytes of Mastocarpus stellatus (Stackhouse) Guiry along Galician coast (NW Spain) by Tasende, Manuel Garcia, Cid, Miguel, Fraga, M. Isabel

“…Qualitative and quantitative differences in carrageenan composition of gametophytes of the rhodophyte Mastocarpus stellatus (Gigartinales) were observed in…”
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Spatial and temporal variations of Chondrus crispus (Gigartinaceae, Rhodophyta) carrageenan content in natural populations from Galicia (NW Spain) by García Tasende, Manuel, Cid, Miguel, Fraga, M. Isabel

“…Qualitative and quantitative differences in carrageenan composition of gametophytes and tetrasporophytes of Chondrus crispus were observed in this study…”
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Adaptive PORT-MVRB estimation: an empirical comparison of two heuristic algorithms by Gomes, M. Ivette, Henriques-Rodrigues, Lígia, Fraga Alves, M. Isabel, Manjunath, B. G.

“…In this article, we deal with an empirical comparison of two data-driven heuristic procedures of estimation of a positive extreme value index (EVI), working…”
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Port-estimation of a shape second-order parameter by Henriques-Rodrigues, Ligia, Gomes, M. Ivette, Alves, M. Isabel Fraga, Neves, Claudia

“…* In this paper we study, under a semi-parametric framework and for heavy right tails, a class of location invariant estimators of a shape second-order…”
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Statistics of extremes for IID data and breakthroughs in the estimation of the extreme value index: Laurens de Haan leading contributions by Gomes, M. Ivette, Canto e Castro, Luísa, Fraga Alves, M. Isabel, Pestana, Dinis

“…In the last decades there has been a shift from the parametric statistics of extremes for IID random variables, based on the probabilistic asymptotic results…”
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Semi-parametric approach to the Hasofer–Wang and Greenwood statistics in extremes by Neves, Cláudia, Fraga Alves, M. Isabel

“…This paper deals with the semi-parametric approach to the problem of statistical choice of extreme domains of attraction. Relying on concepts of regular…”
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Chloroplast microsatellites reveal that metallicolous populations of the Mediterranean shrub Cistus ladanifer L have multiple origins by Quintela-Sabarís, Celestino, Vendramin, Giovanni Giuseppe, Castro-Fernández, Daniel, Fraga, M. Isabel

“…Cistus ladanifer L. (Cistaceae) is a Mediterranean shrub covering different kinds of soils in the Western Mediterranean area. This species has colonised…”
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Chloroplast DNA phylogeography of the shrub Cistus ladanifer L. (Cistaceae) in the highly diverse Western Mediterranean region by Quintela-Sabarís, C., Vendramin, G. G., Castro-Fernández, D., Isabel Fraga, M.

“…This study investigated the phylogeographic structure of Cistus ladanifer, in order to locate its Quaternary refugia, reconstruct its recolonisation patterns…”
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Weiss-Hill estimator by Alves, M. Isabel Fraga

“…In this paper the asymptotic distributional behaviour is derived for a new estimator for the extreme value index γ of distribution, which is a combination of…”
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PORT Hill and Moment Estimators for Heavy-Tailed Models by Gomes, M. Ivette, Alves, M. Isabel Fraga, Santos, Paulo Araújo

“…In this article, we use the peaks over random threshold (PORT)-methodology, and consider Hill and moment PORT-classes of extreme value index estimators. These…”
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Testing Extreme Value Conditions — an Overview and Recent Approaches by Cláudia Neves, M. Isabel Fraga Alves

“…The aim of this paper is to give a brief overview about several tests published in the context of statistical choice of extreme value domains and for assessing…”
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Mixed moment estimator and location invariant alternatives by Fraga Alves, M. Isabel, Gomes, M. Ivette, de Haan, Laurens, Neves, Cláudia

“…A new class of estimators of the extreme value index is developed. It has a simple form and is asymptotically very close to the maximum likelihood estimator…”
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A Note on Second Order Conditions in Extreme Value Theory: Linking General and Heavy Tail Conditions by M. Isabel Fraga Alves, M. Ivette Gomes, Laurens de Haan, Cláudia Neves

“…Second order conditions ruling the rate of convergence in any first order condition involving regular variation and assuring a unified extreme value limiting…”
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Peaks Over Random Threshold Methodology for Tail Index and High Quantile Estimation by Paulo Araújo Santos, M. Isabel Fraga Alves, M. Ivette Gomes

“…In this paper we present a class of semi-parametric high quantile estimators which enjoy a desirable property in the presence of linear transformations of the…”
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Improvements in the Estimation of a Heavy Tail by Orlando Oliveira, M. Ivette Gomes, M. Isabel Fraga Alves

“…In this paper, and in a context of regularly varying tails, we suggest new tail index estimators, which provide interesting alternatives to the classical Hill…”
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