Podcasts about copula

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2022.09.15.508099v1?rss=1 Authors: Sitek, K. R., Chandra, N., Sarkar, A., Chandresekaran, B. Abstract: The central auditory system is comprised of multiple subcortical brain structures that sequentially process and refine incoming acoustic signals along the primary auditory pathway. Due to the technical limitations of imaging small structures deep inside the brain, most of our knowledge of the subcortical auditory system is based on research in animal models using invasive methodologies. While recent advances in ultra-high field functional magnetic resonance imaging (fMRI) acquisition have enabled novel investigations of the human subcortex non-invasively, optimal approaches to assessing functional activation and connectivity are still being developed. Traditionally, functional connectivity using fMRI data is estimated with simple correlation matrices. Partial correlations however reveal the connectivity between two regions after removing the effects of all other regions and hence are often more meaningful. Partial correlation analysis is particularly promising in the subcortical auditory system, where sensory information is passed serially from nucleus to nucleus up the primary auditory pathway, providing redundant but also increasingly abstract representations of auditory stimuli (Chechik and Nelken, 2012). In this project, we developed and implemented a Gaussian copula graphical model (GCGM) approach to estimate the partial correlations and thereby infer the functional connectivity patterns within the auditory system. Given the paucity of non-invasive methods for human subcortical investigations, we aim to unveil novel information about the hierarchy and direct connections throughout the human subcortical auditory system. Our results show strong positive partial correlations between contralateral structures throughout the auditory system, particularly in the auditory midbrain and thalamus. We also found positive partial correlations between successive structures in the auditory pathway on each side (left and right), including between auditory midbrain and thalamus, and between primary and associative auditory cortex. Further, we confirmed that these connectivity estimates were unique to the auditory system, as non-auditory regions included as controls - namely, visual cortex and superior frontal cortex - were strongly connected to their contralateral homologues but only minimally connected with auditory brain regions. Additionally, these results were highly stable when splitting the data in half according to the acquisition schemes and computing partial correlations separately for each half of the data, as well as across cross-validation folds. Overall, these results demonstrate that unique functional connectivity patterns along the auditory pathway are recoverable using novel connectivity approaches and that our connectivity methods are reliable across multiple acquisitions. Copy rights belong to original authors. Visit the link for more info Podcast created by PaperPlayer

Zev Weinstein joins Lexman for a discussion about how the copula can be used to describe moral metrics. They discuss how beggardom may be best described using the copula.

David on Twitter - https://twitter.com/LittleFunnyGeek David's Website - http://davidpham87.github.io Linear Algebra - https://en.wikipedia.org/wiki/Linear_algebra Google Colab - https://colab.research.google.com Paperspace - https://www.paperspace.com Copula - https://en.wikipedia.org/wiki/Copula_(probability_theory) Criterium - https://github.com/hugoduncan/criterium/ Matrix - https://github.com/mikera/core.matrix Video Courses: https://clojure.stream https://learnpedestal.com https://learndatomic.com https://learnreitit.com https://learnreframe.com https://learnreagent.com https://www.jacekschae.com

In this episode of the Biblical Languages Podcast, Kevin Grasso talks with Dr. Daniel Wilson about some special clauses in biblical Hebrew: copula clauses and existential clauses. Show notes available at: https://biblingo.org/blog/copula-and-existential-clauses-in-biblical-hebrew/

In this episode, we will learn how to use the Korean copula 이다 (To Be Verb) - 이었다, 이/가 아니다, 이/가 아니었다 in informal, polite, formal forms. https://onlinekoreaned.wordpress.com/2022/05/26/korean-copula-이다/

DESU is a COPULA! But who understands what that even means!

Desu, a Japanese copula, has a few different uses and pronunciations depending on the formality of the situation. Japanese is a very polite and respectful language, and it is important to know when to use each desu.

Desu, a Japanese copula, has a few different uses and pronunciations depending on the formality of the situation. Japanese is a very polite and respectful language, and it is important to know when to use each desu.

On this episode of the world famous Sofa King Podcast, we talk about the creator of a galaxy far, far away, the one and only George Lucas. He’s most famous for the creation of the Star Wars universe, but people forget he was part of the creative force behind Indiana Jones and one of the ultimate pioneers of special and visual effects in cinema. Most love him for his technical advancements, but some bemoan what he did to cinema, moving it from content to spectacle. And then, too, there was Jar Jar Binks… George Lucas was born in the small town of Modesto, California to a couple of blue collar parents who ran a small walnut ranch and sold office supplies. His biggest hobby growing up was cars and racing, and he even had plans to become a professional race car driver. This dream went up in smoke when he suffered a horrible car crash while racing, and it scared the thrill right out of him. Instead, a friend suggested he follow up with his second biggest passion, which was film. He attended a local community college and then transferred to the fledgling film studies department at USC, where he met incredible talent, from Francis Ford Copula to Steven Spielberg and countless others. He graduated from USC, got drafted, got booted due to health reasons, and went back to USC as a graduate student. Here, he and Copula had the ballsy decision to create their own indie film studio called American Zoetrope, designed to give upstart directors a chance to make films without big studio money. His first film was THX1138 which did poorly at the box office, but it was followed by the cult classic American Graffiti, which did incredibly well at the box office and was Oscar nominated. This got him a golden ticket to turn his passion project—a little science fiction serial he’d been working on—into a film. He directed the first Star Wars and released it in 1977. Nobody expected the film to do well, but it became a global phenomenon. He based the film on Joseph Campbell’s notion of the Archetypical Romantic Quest, something nobody had done in Hollywood, but something virtually everyone does today. This was the start of not just George Lucas’ impact on popular culture, but his climb to become the wealthiest entertainer on earth (which he is as of this recording). It was a fluke, really. He turned down a raise from Fox to write and direct Star Wars in order to retain rights to sequels and merchandising. Fox Studios never dreamed there would be sequels to this strange thing, and nobody made money merchandising, so they struck the deal. Within a year, Lucas was a multi-millionaire. From there, he went on to launch the Indiana Jones movies and produce more Star Wars. Empire Strikes Back and Return of the Jedi were both smashes, as were the Indiana Jones movies, and along the way, he created Industrial Light and Magic to help foster technological innovation in film. From the 80s on, if you watched a sci-fi block buster with crazy effects, odds are it was done by ILM. He also created THX sound systems—the gold standard for movie theaters even to this day—and the company Lucasarts, which created video games, novels, comics, and toys. All of this led to George Lucas being not just a household name, but a billionaire and a myth maker. He released the notorious prequels to mixed reviews, and he ultimately sold his company to Disney for just over $4 Billion dollars. Not bad for a greaser from Modesto… Special thanks to guest host Jason Roskam for sharing his knowledge of all things Lucas. He’s co-host of All Things Star Wars, which is part of the Podbelly family of podcasts.   Visit Our Sources: https://www.biography.com/filmmaker/george-lucas https://en.wikipedia.org/wiki/George_Lucas https://www.rottentomatoes.com/celebrity/george_lucas https://www.forbes.com/profile/george-lucas/#3dd21c736e63 https://www.architecturaldigest.com/story/george-lucas-buys-beachfront-home-in-carpinteria-california https://www.

Today we start with a beautiful song and we will talk about "Copula verbs" and more ...

Today we start with a beautiful song and we will talk about "Copula verbs" and more ...

Part 2 of our discussion of souls, eschatology, and the elven afterlife examines the properties inherent to fëa, including thought transmission, and then we discuss elven resurrection! Show Notes Join Athrabeth's new Discord! Tolkien and Inspiration: A Multidisciplinary Symposium at the Morgan Library Tensing the Copula by David Lewis, the philosophical essay jude referenced in this episode. (note: I kinda made a hash out of explaining why my brain leapt from tolkien’s philosophical musing on how the bodies are the same to the much more complicated topics advanced in this paper, but if you’re interested in checking it out anyway, heres a link) Works Referenced This Episode J.R.R. Tolkien, Christopher Tolkien (ed.), "Laws and Customs of the Eldar", published in Morgoth's Ring M. Devaux, with the assistance of Christopher Tolkien and Carl F. Hostetter (ed.), "Fragments on elvish reincarnation", published in La Feuille de la Compagnie 3 J.R.R. Tolkien , "Ósanwe-kenta", published in Vinyar Tengwar issue 39 J.R.R. Tolkien, Christopher Tolkien (ed.), "Glorfindel", published in The Peoples of Middle-earth

This week we talk about "ii" adjectives and copula.As well as answer questions about what music I like and what is up with the 30 day challenge!If you have questions please send them to manga-sensei.com

This week we talk about "ii" adjectives and copula.As well as answer questions about what music I like and what is up with the 30 day challenge!If you have questions please send them to manga-sensei.com

Thu, 8 Oct 2015 12:00:00 +0100 https://edoc.ub.uni-muenchen.de/18757/ https://edoc.ub.uni-muenchen.de/18757/1/Rose_Doro.pdf Rose, Doro ddc:310, ddc:300, Fakultät für Mathematik, Informat

This thesis presents several non-parametric and parametric models for estimating dynamic dependence between financial time series and evaluates their ability to precisely estimate risk measures. Furthermore, the different dependence models are used to analyze the integration of emerging markets into the world economy. In order to analyze numerous dependence structures and to discover possible asymmetries, two distinct model classes are investigated: the multivariate GARCH and Copula models. On the theoretical side a new dynamic dependence structure for multivariate Archimedean Copulas is introduced which lifts the prevailing restriction to two dimensions and extends the multivariate dynamic Archimedean Copulas to more than two dimensions. On this basis a new mixture copula is presented using the newly invented multivariate dynamic dependence structure for the Archimedean Copulas and mixing it with multivariate elliptical copulas. Simultaneously a new process for modeling the time-varying weights of the mixture copula is introduced: this specification makes it possible to estimate various dependence structures within a single model. The empirical analysis of different portfolios shows that all equity portfolios and the bond portfolios of the emerging markets exhibit negative asymmetries, i.e. increasing dependence during market downturns. However, the portfolio consisting of the developed market bonds does not show any negative asymmetries. Overall, the analysis of the risk measures reveals that parametric models display portfolio risk more precisely than non-parametric models. However, no single parametric model dominates all other models for all portfolios and risk measures. The investigation of dependence between equity and bond portfolios of developed countries, proprietary, and secondary emerging markets reveals that secondary emerging markets are less integrated into the world economy than proprietary. Thus, secondary emerging markets are more suitable to diversify a portfolio consisting of developed equity or bond indices than proprietary

Un problème important en statistiques est de trouver une loi de probabilité jointe entre deux variables à partir de ses lois marginales. Dans le cas de deux variables, les densités marginales f1(x) et f2(y) sont liées à leurs distribution jointe f(x,y) via des intégrations suivant les deux axes horizontal et vertical. Ce problème ressemble à un problème de reconstruction d'image en tomographie où on chercherait à reconstruire une image à partir de seulement deux projections. Ce problème est un problème mal-posé au sens qu'il admet une infinité de solutions, et justement, la notion de "Copula" qui permet de caractériser l'ensemble des lois jointes avec des marginales données, peut être utilisé en tomographie pour caractériser l'ensemble des images compatibles avec deux projections. On pourra alors rechercher une solution particulière dans cet ensemble. A l'inverse, nous pensons que les techniques de reconstruction d'image peuvent apporter une nouvelle voie dans la détermination d'une loi jointe à partir de ses lois marginales, un sujet qui est très important en inférence statistiques. An important problem in statistics is determining a joint probability distribution from its marginals. In 2D case, the marginal probability density functions f1(x) and f2(y) are related to their joint distribution f(x,y) via the horizontal and vertical line integrals. So, the problem of determining f(x,y) from f1(x) and f2(y) is an ill-posed inverse problem. In statistics the notion of emph{copula} is exactly introduced to obtain a solution to this problem. Interestingly, this is also a problem encountered in X ray tomography image reconstruction where f(x,y) is an image representing the distribution of the material density and f1(x) and f2(y) are the horizontal and vertical line integrals. In this talk we try to link the notion of copula to X ray Computed Tomography (CT) and to see if we can use the methods used in each domain to the other one. Ceci est un travail commun avec Doriano Pougaza et Jean Francois Bercher. Ali Mohammad-Djafari. Supélec. Vous pouvez entendre l'intervention, tout en visualisant le Power Point, en cliquant sur ce lien : http://epn.univ-paris1.fr/modules/ufr27statim/UFR27STATIM-20090123-Djafari/UFR27STATIM-20090123-Djafari.html. Ecouter l'intervention : Bande son disponible au format mp3 Durée : 49 mn

In this paper we extend the standard approach of correlation structure analysis in order to reduce the dimension of highdimensional statistical data. The classical assumption of a linear model for the distribution of a random vector is replaced by the weaker assumption of a model for the copula. For elliptical copulae a correlation-like structure remains but different margins and non-existence of moments are possible. Moreover, elliptical copulae allow also for a copula structure analysis of dependence in extremes. After introducing the new concepts and deriving some theoretical results we observe in a simulation study the performance of the estimators: the theoretical asymptotic behavior of the statistics can be observed even for a sample of only 100 observations. Finally, we test our method on real financial data and explain differences between our copula based approach and the classical approach. Our new method yields a considerable dimension reduction also in non-linear models.

Building on the work of Bedford, Cooke and Joe, we show how multivariate data, which exhibit complex patterns of dependence in the tails, can be modelled using a cascade of pair-copulae, acting on two variables at a time. We use the pair-copula decomposition of a general multivariate distribution and propose a method to perform inference. The model construction is hierarchical in nature, the various levels corresponding to the incorporation of more variables in the conditioning sets, using pair-copulae as simple building blocs. Pair-copula decomposed models also represent a very flexible way to construct higher-dimensional coplulae. We apply the methodology to a financial data set. Our approach represents the first step towards developing of an unsupervised algorithm that explores the space of possible pair-copula models, that also can be applied to huge data sets automatically.

In general, risk of an extreme outcome in financial markets can be expressed as a function of the tail copula of a high-dimensional vector after standardizing marginals. Hence it is of importance to model and estimate tail copulas. Even for moderate dimension, nonparametrically estimating a tail copula is very inefficient and fitting a parametric model to tail copulas is not robust. In this paper we propose a semi-parametric model for tail copulas via an elliptical copula. Based on this model assumption, we propose a novel estimator for the tail copula, which proves favourable compared to the empirical tail copula, both theoretically and empirically.