نتایج جستجو برای: copula

تعداد نتایج: 3447  

Journal: :Journal of Business & Economic Statistics 2018

Journal: :تحقیقات آب و خاک ایران 0
مهدی امیدی محسن محمدزاده سعید مرید

to analyze and manage the risk of drought in a region, access to some certain information is required, the most important of which is the frequency of drought severity-duration. realizing the high correlation of these factors, one must pick up a method that pinpoint the relation and effects of these factors on drought analysis. in this paper, numerous copula families were employed to model the ...

2012
Liang Peng Yongcheng Qi Ingrid Van Keilegom

Copulas are used to depict dependence among several random variables. Both parametric and non-parametric estimation methods have been studied in the literature. Moreover, profile empirical likelihood methods based on either empirical copula estimation or smoothed copula estimation have been proposed to construct confidence intervals of a copula. In this paper, a jackknife empirical likelihood m...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه تفرش - دانشکده مهندسی صنایع 1390

در این پژوهش با به کارگیری توابع copula به عنوان ابزاری برای ارتباط برقرار کردن بین توابع احتمال متغیرهای تصادفی، به معرفی مدلی برای تصمیم گیری در خصوص انتخاب پورتفولیو پرداخته و در نهایت با مقایسه ی مدل یاد شده با مدل مشهور مارکویتز به بیان نقاط قوت و ضعف آن می پردازیم. نتایج به دست آمده در این پژوهش نشان از توانایی توابع copula در پاسخگویی به پرسش سرمایه گذار در خصوص انتخاب سهام موجود در پور...

2010
Adrian Dobra Alex Lenkoski A. LENKOSKI

We propose a comprehensive Bayesian approach for graphical model determination in observational studies that can accommodate binary, ordinal or continuous variables simultaneously. Our new models are called copula Gaussian graphical models (CGGMs) and embed graphical model selection inside a semiparametric Gaussian copula. The domain of applicability of our methods is very broad and encompass m...

Journal: :Kybernetika 2011
Andrea Stupnanová Anna Kolesárová

Copulas were introduced by Sklar [13] to capture the stochastic dependence structure of random variables. Recall that for n ≥ 2, a function C : [0, 1] → [0, 1] is called an n-dimensional copula (n-copula, for short) whenever it is a restriction of an ndimensional distribution function with all univariate margins uniformly distributed on [0, 1]. Hence an n-copula is characterized by the properties:

2011
A. LENKOSKI

We propose a comprehensive Bayesian approach for graphical model determination in observational studies that can accommodate binary, ordinal or continuous variables simultaneously. Our new models are called copula Gaussian graphical models (CGGMs) and embed graphical model selection inside a semiparametric Gaussian copula. The domain of applicability of our methods is very broad and encompasses...

2012
Mélanie Rey Volker Roth

We present a reformulation of the information bottleneck (IB) problem in terms of copula, using the equivalence between mutual information and negative copula entropy. Focusing on the Gaussian copula we extend the analytical IB solution available for the multivariate Gaussian case to distributions with a Gaussian dependence structure but arbitrary marginal densities, also called meta-Gaussian d...

2008
KLARA GOETHALS

Copulas and frailty models are important tools to model bivariate survival data. Equivalence between Archimedean copula models and shared frailty models, e.g., between the Clayton-Oakes copula model and the shared gamma frailty model, has often been claimed in the literature. In this note we show that, in both models, there is indeed the well known equivalence between the copula functions; the ...

2007
Paul Embrechts

Copula modeling has taken the world of finance and insurance, and well beyond, by storm. Why is this? In this paper I review the early start of this development, discuss some important current research, mainly from an applications point of view, and comment on potential future developments. An alternative title of the paper would be “Demystifying the copula craze”. The paper also contains what ...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید