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Beating the Swedish Market : A dynamic approach to Value Investing using Modern Portfolio TheoryKarlsson, Viktor, Nygren, Emil January 2012 (has links)
Previous research has confirmed the existence of a value premium in a wide array of markets and using this value stock anomaly has yielded superior performance. This thesis investigates if one could take advantage of the existence of a value premium to deploy a dynamic investment strategy on the Swedish stock market (OMXS30) with focus on minimizing risk to achieve higher risk adjusted performance than the stock market index. The investment strategy implemented use Market-to-Book-Value to screen for both entry and exit signals and Modern Portfolio Theory, using the minimum-variance portfolio with short-selling constraints, to allocate assets within the portfolio. The investment strategy is evaluated using the Modigliani-Modigliani Risk Adjusted Performance measure. Conclusions from the thesis are that the strategy does outperform the Swedish stock market index, both in terms of nominal return and risk-adjusted performance. The suboptimal behaviour of investors where they overreact to signals and unconsciously rely on heuristics is used to explain why this is possible. Market-to-Book-Value, using the first quartile as entry signal and third quartile as exit signal, is considered to be a successful key ratio to screen for value stocks.
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Adaptive dispersion compensation and ultrasonic imaging for structural health monitoringHall, James Stroman 29 June 2011 (has links)
Ultrasonic guided wave imaging methods offer a cost-effective mechanism to perform in situ structural health monitoring (SHM) of large plate-like structures, such as commercial aircraft skins, ship hulls, storage tanks, and civil structures. However, current limits in imaging quality, environmental sensitivities, and implementation costs, among other things, are preventing widespread commercial adoption. The research presented here significantly advances state of the art guided wave imaging techniques using inexpensive, spatially distributed arrays of piezoelectric transducers. Novel adaptive imaging techniques are combined with in situ estimation and compensation of propagation parameters; e.g., dispersion curves and transducer transfer functions, to reduce sensitivity to unavoidable measurement inaccuracies and significantly improve resolution and reduce artifacts in guided wave images. The techniques can be used not only to detect and locate defects or damage, but also to characterize the type of damage. The improved ability to detect, locate, and now characterize defects or damage using a sparse array of ultrasonic transducers is intended to assist in the establishment of in situ guided wave imaging as a technically and economically viable tool for long-term monitoring of plate-like engineering structures.
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Estimation And Hypothesis Testing In Stochastic RegressionSazak, Hakan Savas 01 December 2003 (has links) (PDF)
Regression analysis is very popular among researchers in various fields but almost all the researchers use the classical methods which assume that X is nonstochastic and the error is normally distributed. However, in real life problems, X is generally stochastic and error can be nonnormal. Maximum likelihood (ML) estimation technique which is known to have optimal features, is very problematic in situations when the distribution of X (marginal part) or error (conditional part) is nonnormal.
Modified maximum likelihood (MML) technique which is asymptotically giving the estimators equivalent to the ML estimators, gives us the opportunity to conduct the estimation and the hypothesis testing procedures under nonnormal marginal and conditional distributions. In this study we show that MML estimators are highly efficient and robust. Moreover, the test statistics based on the MML estimators are much more powerful and robust compared to the test statistics based on least squares (LS) estimators which are mostly used in literature. Theoretically, MML estimators are asymptotically minimum variance bound (MVB) estimators but simulation results show that they are highly efficient even for small sample sizes. In this thesis, Weibull and Generalized Logistic distributions are used for illustration and the results given are based on these distributions.
As a future study, MML technique can be utilized for other types of distributions and the procedures based on bivariate data can be extended to multivariate data.
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Algoritmos de imagen y sonido digital con restricciones de tiempo realAlventosa Rueda, Francisco Javier 28 February 2022 (has links)
[ES] En la actualidad, cada vez existen más y más tareas que necesitamos exportar y
automatizar en dispositivos portables de bajo consumo que se alimentan de baterías, en los cuales
es imprescindible realizar un uso "optimo" de la energía disponible con la finalidad de no drenarlas
rápidamente.En la sección primera de esta tesis, "Filtros de señales de audio digital", "optimizamos" las implementaciones de diferentes filtros, tanto generales como específicos, para aplicaciones de sonido digital diseñados e implantados en plataformas basadas en las arquitecturas ARM®. Como filtros generales, trabajamos con los filtros FIR, IIR y Parallel IIR, siendo este tipo de filtros implementados a bajo nivel con instrucciones vectoriales NEON®. Finalmente, se implementa un filtro de separación de señales conocido como "Beamforming", el cual plantea después de su estudio, la problemática de realizar una factorización QR de una matriz relativamente grande en tiempo real, lo cual nos lleva a desarrollar diferentes técnicas de "aceleración" de los cálculos de la misma. En la segunda parte, "Rellenado de mapa de profundidad de una escena", describimos el proceso de rellenado de un mapa de profundidad de una escena capturada a partir del uso de la imagen RGB y de un mapa de profundidad disperso donde únicamente tenemos valores de profundidad en los bordes de los objetos que componen la escena. Estos algoritmos de "rellenado" del mapa de profundidad, también han sido diseñados e implantados en dispositivos basados en la arquitectura ARM®. / [CA] Actualment, cada vegada existixen més i més tasques que tenen la necessitat d'exportar i automatitzar a dispositius portables de baix consum que s'alimenten amb bateríes, als quals es imprescindible realitzar un ús "óptim" de l'energia disponible amb la finalitat de no drenar-les ràpidament.
Part I: Filtres de senyals d'àudio digital
En aquesta secció "optimitzarem" les implementacions de diferents filtres, tant generals com específics, empreats a aplicacions de so digital disenyats e implantats a plataformes basades a les arquitectures ARM®. Com a filtres generals, treballem amb els filtres FIR, IIR y Parallel IIR, sent
aquests tipus de filtres implementats a baix nivell amb instruccions vectorials NEON®. Finalment, s'implementa un filtro de separació de senyals conegut com "Beamforming", el qual planteja després del seu estudi, la problem`atica de realitzar una factorizació QR d'una matriu relativament gran en temps real, i açó ens porta a desenvolupar diferents tècniques "d'acceleració" dels càlculs de la mateixa.
Part II: Emplenat del mapa de profunditat d'una escena
A la secció d'image per computador, descrivim el procés d'emplenat d'un mapa de profunditat d'una escena capturada fent servir l'image RGB i un mapa de profunditat dispers on únicament tenim valors de profunditat als bordes dels objetes que composen l'escena. Aquests algoritmes "d'emplenat" del mapa de profunditat, també han sigut disenyats e implantats a dispositius basats en l'arquitectura ARM®. / [EN] Currently, there are more and more tasks that we need to export and automate in low-consumption mobile devices that are powered by batteries, in which it is essential to make an
"optimum" use of the available energy in order to do not drain them quickly.
Part I: Filters of digital audio signals
In this section we "optimize" the implementations of different filters, both general and specific, for digital sound applications designed and implemented on platforms based on the ARM®. As general
filters, we work with the FIR, IIR and Parallel IIR filters, these types of filters being implemented at a low level with NEON®vector instructions. Finally, a signal separation filter known as "Beamforming"
is implemented, which set out after its study, the problem of performing a QR factorization of a relatively large matrix in real time, which leads us to develop different techniques of "acceleration" of the calculations of it.
Part II: Filling the depth map of a scene
In the computer image section, we describe the process of filling in a depth map of a captured scene using RGB image and a sparse depth map where we only have depth values at the edges of the
objects that make up the scene. These depth map "filling" algorithms have also been designed and implemented in devices based on the ARM® architecture. / Alventosa Rueda, FJ. (2022). Algoritmos de imagen y sonido digital con restricciones de tiempo real [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/181573 / TESIS
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Enhancing ESG-Risk Modelling - A study of the dependence structure of sustainable investing / Utvecklad ESG-Risk Modellering - En studie på beroendestrukturen av hållbara investeringarBerg, Edvin, Lange, Karl Wilhelm January 2020 (has links)
The interest in sustainable investing has increased significantly during recent years. Asset managers and institutional investors are urged to invest more sustainable from their stakeholders, reducing their investment universe. This thesis has found that sustainable investments have a different linear dependence structure compared to the regional markets in Europe and North America, but not in Asia-Pacific. However, the largest drawdowns of an sustainable compliant portfolio has historically been lower compared to the a random market portfolio, especially in Europe and North America. / Intresset för hållbara investeringar har ökat avsevärt de senaste åren. Fondförvaltare och institutionella investerare är, från deras intressenter, manade att investera mer hållbart vilket minskar förvaltarnas investeringsuniversum. Denna uppsats har funnit att hållbara investeringar har en beroendestruktur som är skild från de regionala marknaderna i Europa och Nordamerika, men inte för Asien-Stillahavsregionen. De största värdeminskningarna i en hållbar portfölj har historiskt varit mindre än värdeminskningarna från en slumpmässig marknadsportfölj, framförallt i Europa och Nordamerika.
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MAGNETIC TWEEZERS: ACTUATION, MEASUREMENT, AND CONTROL AT NANOMETER SCALEZhang, Zhipeng 03 September 2009 (has links)
No description available.
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期貨最適避險策略之研究--國際金融性期貨商品實證分析鄭適薰, ZHENG,SHI-XUN Unknown Date (has links)
一、研究動機與目的
由於國際經濟體系日趨複雜,持有資產的不確定性因而增加,投資者為了避免因為資
產報酬過大的波動而造成損失,紛紛尋求迴避風險的工具。而期貨由於具備了高度流
動性,融通功能的保證金制度及公正的中介機構等優點,使其產品種類及交易量日益
擴大,提供了金融資產持有者良好的避險管道。
本研究探討金融性期貨商品在各種避險期間長度及不同到期日的期貨契約,降低風險
的程度是否有差異,並就各避險策略理論,比較其績效。
二、研究期間與樣本。
本研究由華爾街日報及偷敦金融時報抄錄由1988年 1月到1990年1 月共108 週,每週
三金融性商品現貨及期貨收盤價格。包括黃金、英鎊、日圓、西德馬克、瑞士法郎及
S & P 500 NYSE股價指數和T-Bill Euro Dollar利率等九種。
三、研究方法。
主要比較以下三種避險策略降低風險的程度,並研究以期貨避險時,是否愈早簽訂契
約或選擇到期日距今較遠的契約愈能降低風險。
1.天真法則 (Naive Approch)
該策略假設任何資產的現貨與期貨價格變動方向一致且幅度相同。於是為了避免資產
因為價格波動造成損失,投資者的避險策略應該是分別持有數量相同但方向相反的現
貨與期貨部位(position)。如此現貨資產與期貨資產的損益可完全抵消,若不計交易
成本,則造成損失的可能性為零。
2.最小變異數法則 (Minimum Variance Approach)
該法則認為,現貨與期貨價格同方向且等幅度變動的假設並不合理,而將現貨與期貨
所持有的部位視為資產組合 (portfolio),此資產組合價格的變異數視為風險;求出
使該資產組合風險最小的期貨部位。期貨相對現貨的持有比值就是最適避險比率,以
此比率構成資產組合風險最小。
3.風險迴避法則(Risk Aversion Approach)
該法則引用普雷特-亞羅(Pratt-Arrow) 絕對風險迴避的觀念,尋求報酬和風險間的
替代關係,在報酬不為負的要求下,求出使資產組合風險最小的避險比率。此法則由
於衡量的標準更為嚴格,故計算亦較繁複。
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Statistical InferenceChou, Pei-Hsin 26 June 2008 (has links)
In this paper, we will investigate the important properties of three major parts of statistical inference: point estimation, interval estimation and hypothesis testing. For point estimation, we consider the two methods of finding estimators: moment estimators and maximum likelihood estimators, and three methods of evaluating estimators: mean squared error, best unbiased estimators and sufficiency and unbiasedness. For interval estimation, we consider the the general confidence interval, confidence interval in one sample, confidence interval in two samples, sample sizes and finite population correction factors. In hypothesis testing, we consider the theory of testing of hypotheses, testing in one sample, testing in two samples, and the three methods of finding tests: uniformly most powerful test, likelihood ratio test and goodness of fit test. Many examples are used to illustrate their applications.
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