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Card-Shuffling Analysis with Weighted Rank DistanceWu, Kung-sheng 24 June 2007 (has links)
In this paper, we cite two weighted rank distances (Wilcoxon rank and Log rank) to analyze how many times must a deck of 52 cards be shuffled to become
sufficiently randomized. Bayer and Diaconis (1992) used the variation distance as a measure of randomness to analyze the card-shuffling. Lin (2006) used the deviation distance to analyze card-shuffling without complicated mathematics formulas. We provide two new ideas to measure the distance for card-shuffling analysis.
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SVM-based Robust Template Design of Cellular Neural Networks and Primary Study of Wilcoxon Learning MachinesLin, Yih-Lon 01 January 2007 (has links)
This thesis is divided into two parts. In the first part, a general problem of the robust template decomposition with restricted weights for cellular neural networks (CNNs) implementing an arbitrary Boolean function is investigated. In the second part, some primary study of the novel Wilcoxon learning machines is made.
In the first part of the thesis for the robust CNN template design, the geometric margin of a linear classifier with respect to a training data set, a notion borrowed from the machine learning theory, is used to define the robustness of an uncoupled CNN implementing a linearly separable Boolean function. Consequently, the so-called maximal margin classifiers can be devised via support vector machines (SVMs) to provide the most robust template design for uncoupled CNNs implementing linearly separable Boolean functions. Some general properties of robust CNNs with or without restricted weights are discussed. Moreover, all robust CNNs with restricted weights are characterized. For an arbitrarily given Boolean function, we propose an algorithm, which is the generalized version of the well known CFC algorithm, to find a sequence of robust uncoupled CNNs implementing the given Boolean function.
In the second part of the thesis, we investigate the novel Wilcoxon learning machines (WLMs). The invention of these learning machines was motivated by the Wilcoxon approach to linear regression problems in statistics. The resulting linear regressors are quits robust against outliers, as is well known in statistics. The Wilcoxon learning machines investigated in this thesis include Wilcoxon Neural Network (WNN), Wilcoxon Generalized Radial Basis Function Network (WGRBFN), Wilcoxon Fuzzy Neural Network (WFNN), and Kernel-based Wilcoxon Regressor (KWR).
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Evaluating multiple endpoints in heart failure clinical trialsYang, Yijun 12 March 2016 (has links)
The selection of the best response variables in a clinical trial is often not straightforward; the primary endpoint of a trial should be clinically relevant, directly related to the primary objective of the trial, and with favorable efficiency to detect the treatment benefit with a reasonable sample size and duration of the trial. With the recent success in the management of heart failure, the mortality rate has dropped significantly compared to two decades ago, and patients with heart failure have high rates of hospitalization and morbid complications along with multiple symptoms and severe limitations in daily activities. Although mortality still remains important as a measure of the clinically relevant benefit and the safety of the intervention, with the low event rate of mortality, it requires large and longer clinical trials to detect treatment benefit of new intervention using mortality as the sole primary endpoint. Thus most heart failure trials use the combined endpoint of death and a second efficacy outcome, such as hospitalizations. This is often analyzed with time-to-first-event survival analysis which ignores possible subsequent hospitalization events and treating the death and first hospitalization equally in the importance and hierarchy of clinical relevance. Accounting for the recurrent events or subsequent death after the hospitalization(s) provides more detailed information on the disease-control process and treatment benefit.
In this dissertation we propose a hierarchical endpoint with death in the higher priority and number of hospitalization events in the lower priority as primary endpoint to assess experimental treatment benefit versus a control using a non-parametric generalized Gehan-Wilcoxon test. In addition to the hierarchical endpoint, we also evaluated assessment of experimental treatment benefit on recurrent events with a multi-state model using extended stratified Cox model, considering the multi-states in which patients might transition during the study. We compared the false positive rate and power of the above mentioned methods with the composite endpoint approach and recurrent event endpoint approach analyzed using Andersen-Gill, WLW, and PWP models in simulation studies. Finally we applied all evaluated procedures to the Digitalis Investigation Group (DIG) trial.
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Distribution-Free Confidence Intervals for Difference and Ratio of MediansPrice, Robert M., Bonett, Douglas G. 01 December 2002 (has links)
The classic nonparametric confidence intervals for a difference or ratio of medians assume that the distributions of the response variable or the log-transformed response variable have identical shapes in each population. Asymptotic distribution-free confidence intervals for a difference and ratio of medians are proposed which do not require identically shaped distributions. The new asymptotic methods are easy to compute and simulation results show that they perform well in small samples.
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Performance evaluation of Multithreading, Hashtables, and Anonymous Functions for Rust and C++ : in Game DevelopmentNordström, Oscar, Raivio, Lowe January 2023 (has links)
Background C++ is a programming language introduced in 1985, while Rust was introduced in 2010. Rust focuses on speed and safety and was created with the need for concurrency in mind.These languages have different memory management systems as C++ originally only supported manual memory management, while Rust's memory management system performs checks before the compilation of the application begins to prevent issues such as dereferencing null pointers, use-after-free errors, and buffer overflows.These languages' standard libraries have some features in common such as anonymous functions, hashtables, and threads.These features can be utilized in games by implementing resource management with hashtables, event systems with anonymous functions, and parallelization with threads. Objectives The objectives included designing two equivalent game implementations, one with Rust and one with C++. These games were the testing grounds used to test the standard library implementations of anonymous functions, hashtables, and threads. These features' execution times were measured and compared to determine if there existed a difference between them in Rust and C++. Methods Using Raylib, two identical games have been created that utilized and collected execution time metrics for anonymous functions, hashtables, and threads. These games were executed 90 times for a duration of 10 seconds. When all tests were completed, the execution time data was compiled. This data was visualized and analyzed to determine the differences in execution time between Rust and C++ for these specific features. Results The results indicate that Rust performs better at creating anonymous functions, searching and deleting entries in hashtables, and joining threads. The results also reveal that C++ performs better at calling anonymous functions, inserting into hashtables, and creating and starting threads. Conclusions A substantial statistical difference exists between the execution times for the selected features in Rust and C++. The performance differences are significant to the extent that a developer can gain some performance by selecting the language that performs best depending on their needs. In the end, both languages are well suited for game development based on the result of this limited study.
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A abordagem não paramétrica para avaliação da percepção de sustentabilidade do sistema de produção de arroz de terras altas / The non-parametric approach for evaluation of the perception of sustainability of high lands rice production systemInga de La Cruz, Elvis Edgard 19 August 2015 (has links)
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Previous issue date: 2015-08-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This study aimed, expand the method of Production Systems Sustainability Perception Rice High -MPSAT Lands. The choice of this method is justified by the fact that it has a good theoretical framework and be easily understood by the actors; however, it lacks nonparametric statistical approach. They were interviewed actors in the production chain of upland rice in Mato Grosso on two occasions, in 2006/07, when the MPSATA and 2014 was developed as part of this research. The methodology transformed the qualitative elements that make up the MPSATA (questions, attributes, indicators, key variables, secondary counselors, primary guiding and sustainability dimensions) for ordinal type and identified the sense of the order of the categories of these elements. Then it verified the significance of matched elements, considering the 2007 and 2014 surveys, with the IBM-SPSS 21. Later the element values were calculated. These elements have as a data source practices and managements carried out along the production chain. The end result of the research was the development of Parametric Method Not for Perception Sustainability Highlands Rice Production System - MPSATA-NP. The results obtained by MPSATA-NP allowed to accept or reject in statistical terms, if there were significant differences between the values of the features found in different eras who were surveyed, revealing that the 221 questions elements, eleven have statistical difference between their medians (three environmental dimension, two of the socioeconomic scale, four in the economic dimension and two territorial dimension). The other sustainability factors have changes compared to paired terms, however, it can´t be said that these elements are in fact different and represent more or less sustainable production conditions. So it follows that not hear significant change in the perception of the actors with respect to the sustainability of the land rice production system in the region. / O presente trabalho teve como objetivo, ampliar o método da Percepção de Sustentabilidade de Sistemas de Produção Arroz de Terras Altas -MPSAT1. A escolha desse método se justifica pelo fato do mesmo possuir uma boa estrutura teórica e ser de fácil compreensão pelos atores, no entanto, carece de abordagem estatística não paramétrica. Foram entrevistados atores da cadeia produtiva de arroz de terras altas em Mato Grosso em dois momentos, em 2006/07, quando o MPSATA foi desenvolvido e 2014, como parte integrante da presente pesquisa. A metodologia utilizada transformou os elementos qualitativos que compõem o MPSATA (quesitos, atributos, indicadores, variáveis essenciais, orientadores secundários, orientadores primários e dimensões de sustentabilidade) para o tipo ordinal e identificou o sentido da ordem das categorias desses elementos. Em seguida foi verificada a significância dos elementos emparelhados, considerando os levantamentos de 2007 e 2014, com o software IBM-SPSS 21. Posteriormente foram calculados os valores dos elementos. Estes elementos possuem como fonte de dados as práticas e manejos realizados ao longo da cadeia produtiva. O resultado final da pesquisa foi a elaboração do Método Não Paramétrico para a Percepção de Sustentabilidade de Sistema de produção de Arroz de Terras Altas – MPSATA-NP. Os resultados obtidos pelo MPSATA-NP permitiram aceitar ou rejeitar em termos estatísticos, se havia diferenças significativa entre os valores dos elementos quesitos encontrados nas diferentes épocas que foram pesquisados, revelando que dos 221 elementos quesitos, onze possuem diferença estatística entre as suas medianas (três da dimensão ambiental, duas da dimensão socioeconômica, quatro da dimensão econômica e dois da dimensão territorial). Os outros elementos de sustentabilidade possuem mudanças, no entanto, não pode-se se afirmar sejam de fato diferentes e que representem condições de produção mais ou menos sustentáveis. Assim, se conclui que não ouve mudança significativa na percepção dos atores com respeito à sustentabilidade do sistema de produção de arroz de terras na região.
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Kungsängsverkets kväverening : inverkan på den interna fosforbelastningen i Ekoln / Kungsängsverkets nitrogen removal : effect on the internal phosphosous load in EkolnLousa-Alvin, Alexandra January 2011 (has links)
Många sjöar är idag påverkade av mänsklig aktivitet, bland annat är 1 % av Sveriges sjöar eutrofierade, däribland Ekoln. Ekoln är en stor sjö i Uppsala län söder om Uppsala som länge varit eutrofierad. Fyrisån och Örsundaån är de största inflödena till Ekoln och Sävjaån är ett betydande biflöde till Fyrisån. Kungsängsverket är Uppsalas reningsverk och har sitt utlopp i Fyrisån och som ett led i att minska eutrofieringen byggdes fosforreningen ut 1972. Fosforhalterna i Ekoln sjönk och algblomningarna blev färre. Kvävereningen byggdes ut 1999 och i detta arbete utvärderas detta reningssteg. Hypotesen är att när ammonium minskar i bottenvattnet kommer syrgasförhållandena att förbättras på grund av minskad ammoniumnedbrytning som förbrukar syrgas. Med ökad halt syrgas är det känt sedan tidigare studier att den interna fosforbelastningen och algblomningen minskar. För att undersöka om det skett en signifikant minskning av näringsämnen i intransporten till Ekoln och av halterna i Ekoln utfördes statistiska test av ämnena för perioden före och perioden efter införandet av kväverening. Intransporterna modellerades även i StormTac. Resultatet visar att det skett en minskning av kväve- och ammoniumtransport och en ökning av fosfor-, fosfat- och TOC-transport. I Ekoln har en minskning påvisats i ammonium-, totalfosforhalt och en ökning i fosfat- och TOC-halt. Ammoniumhalten har minskat i bottenvattnet så den minskade intransporten av ammonium gett en effekt. Fosfor- och fosfathalten har inte förändrats signifikant i bottenvattnet, men det har skett en viss minskning av fosfor och en viss ökning av fosfat i Ekoln perioden 1990-1998 till 2000-2010. Även syrgashalten har ökat i bottenvattnet. Att det inte skett signifikanta förändringar i fosfor, fosfat och syrgas tyder på att intransporten till vattenmassan inte förändrats. Ökade TOC-halter leder till ökad nedbrytning där syrgas förbrukas i bottenvattnet. Det är möjligt att situationen sett ännu värre ut i Ekoln om inte kväveutsläppen minskat.
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[en] UNDERPRICING IN THE BRAZILIAN STOCK MARKET: OCCURENCE AND RELATED FACTORS / [pt] UNDERPRICING NO MERCADO ACIONÁRIO BRASILEIRO OCORRÊNCIA E FATORES RELACIONADOSANTHONY COELHO SADKOWSKI 30 November 2018 (has links)
[pt] O objetivo deste trabalho é verificar a ocorrência do underpricing no mercado brasileiro e analisar sua relação com fatores internos, externos da empresa e da oferta. O underpricing é considerado uma anomalia de mercado, pois proporciona para os investidores ganhos elevados com a mesma composição de risco. Para as empresas, a ocorrência do underpricing no IPO compromete a eficiência da oferta, uma vez que reduz o montante arrecadado. Este fenômeno foi estudado nas décadas de 80 e 90, porém somente na última década estudos começaram a ser realizados com foco no mercado brasileiro. Desta forma, foi observada a ocorrência do underpricing no mercado brasileiro em uma amostra composta por 30 IPO entre os anos de 2010 a 2016, e para analisar a relação dos fatores foi aplicado a análise de cluster aliada ao teste não paramétrico de Wilcoxon. / [en] The objective of this paper is to verify the occurrence of underpricing in the Brazilian market and to analyze its relationship with internal, external factors of the company and the offer. Underpricing is considered a market anomaly as it provides investors with high returns with the same risk composition. For companies, the occurrence of underpricing in the IPO compromises the efficiency of the offer, since it reduces the amount collected. This phenomenon was studied in the 80 s and 90 s, but only in the last decade studies began to be carried out focusing on the Brazilian market. Thus, underpricing in the Brazilian market was observed in a sample composed of 30 IPO between the years 2010 and 2016, and to analyze the relationship of factors was applied to the cluster analysis allied to the Wilcoxon nonparametric test.
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Análise de correlação de longo alcance no registro da atividade elétrica cortical no fenômeno da depressão alastrante em ratosNASCIMENTO, Rosângela Silveira do 29 February 2008 (has links)
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Previous issue date: 2008-02-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In the present work we analyze the dynamics of electrical cortical activity during the phenomenon of spreading depression (DA) and during the periods before and after this phenomenon. The characteristic of DA is reduced amplitude of spontaneous electrical activity that occurs in neural tissue after the application of stimulus that can be electrical, chemical, mechanical, luminous etc. In order to study properties of time series of electrical cortical activity recorded by ECoG (electrocortiogram) before,during and after DA, we apply Detrended Fluctuation Analysis(DFA). This method is designed to quantify long term correlations (memory) in temporal series such ECoG register. The method was successfully applied in studies of DNA sequences and non-stationary time series as heart rate variability, stride intervals, financial time series etc. The application of DFA results in scaling exponentα that quantifies correlation properties of nonlinear dynamical systems. This experiment indicates if temporal series posses long term correlations. In this work we calculate exponent α for different intervals: control (before the stimulus), after the stimulus, during the avalanche, during DA and after DA for two experimental groups of rats, nourished and malnourished. For both experimental groups the values of exponent α indicates persistent behavior for all intervals except during the avalanche in which correlations degrade. The presence of long term correlations in physiological time series observed in healthy organisms represents complexity that guaranties the organism’s adaptability to stress and disease. The absence of correlations during the avalanche indicates the loss of this complexity. Non-parametric Wilcoxon test was used to compare mean values of exponents α for all intervals of analyzed time series. In cases of nourished rats, the mean values ofα are significantly different for control, stimulus, avalanche, DA and after-DA intervals. Wilcoxon test was also used to compare mean values of α for corresponding intervals for the two experimental groups. The result is significant difference in mean values of α for control, stimulus avalanche, DA and after DA intervals between two experimental groups. The hypothesis that α =0.5 for avalanche intervals was not rejected by test, confirming the loss of correlations in this phase. Comparison of mean values of α for different intervals (control, stimulus, DA and after DA) with avalanche using the Wilcoxon test results in significant difference between two groups. / O presente estudo se propõe a analisar a dinâmica da atividade elétrica cortical durante o fenômeno da depressão alastrante (DA) e nos períodos que antecede e sucede o fenomêno. A DA é caracterizada pela redução da amplitude da atividade elétrica espontânea que ocorre no tecido neural, após a aplicação de um estímulo de natureza elétrica, química, mecânica, luminosa e outros. Visando estudar o comportamento da série temporal da atividade elétrica cortical, registrada no ECoG (eletrocorticograma), durante a DA e nos períodos que precede e sucede o fenômeno, foi aplicado o método do DFA (Detrended Fluctuation Analysis). Este método permite quantificar a existência de correlação de longo alcance (memória) numa série temporal, como é o caso do registro do ECoG. Anteriormente, o método foi aplicado em seqüências de DNA e no estudo de séries temporais não estacionárias, tais como, dinâmica da variabilidade cardíaca, flutuações de eletroencefalograma de humanos, intervalos entre passos sucessivos de humanos, séries econômicas e outros. A aplicação do DFA numa série temporal permite a determinação de um expoente de escalonamento α, que pode contribuir para a compreensão das propriedades dos sistemas dinâmicos não lineares. Este expoenteα revela se a série temporal apresenta correlação de longo alcance ou não. Neste trabalho os expoentes α foram calculados nas fases de controle, estímulo, avalanche, DA e após a DA para o ECoG, em dois grupos experimentais, ratos nutridos e ratos desnutridos. Em ambos os grupos experimentais, os valores obtidos para o expoente de escalonamento α denotam que a série temporal do ECoG apresenta correlação persistente (comportamento da série no presente se mantém no futuro) em todas as fases do processo com exceção da avalanche, período no qual ocorre perda de correlação. A presença de correlação de longo alcance numa série temporal biológica é uma resposta sempre observada em organismos saudáveis cuja complexidade do sinal registrado garante a adaptabilidade do organismo a situações de estresse e/ou distúrbios. Enquanto a ausência de correlação, observada na avalanche, indica a perda de propriedades fractais nos sistemas fisiológicos. O uso do método não-paramétrico de Wilcoxon, para comparar os valores médios dos expoentes α obtidos para o grupo de animais nutrido, durante as fases de controle, estimulação, DA, após DA, revelou que essas diferentes fasesdiferem significativamente. Os valores médios dos expoentes α obtidos para o grupo de animais desnutrido, durante as fases de controle, estimulação, DA, após DA, também não foram significativamente diferentes, quando comparados pelo método de Wilcoxon. Na comparação dos valores médios de α nas fases de controle, estimulação, DA, após DA entre os dois grupos de animais (nutrido e desnutrido) o teste de Wilcoxon revelou que as médias dos expoentes α em cada fase para os animais nutridos diferem significativamente daquelas obtidas para os animais desnutridos. Na avalanche a hipótese de que o expoente α é igual a 0,5, não foi rejeitada pelo teste de Wilcoxon, ou seja, o teste confirmou a perda de correlação nessa fase. Na comparação entre as médias dos expoentes α nos diferentes intervalos (controle, estimulação, DA, após DA) com o valor do expoente α na avalanche, o teste de Wilcoxon acusou diferença significativa tanto no grupo dos nutridos como no grupo dos desnutridos.
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Utvärdering av tre olika metoder för Van Gieson Elastin färgning på Kolorektalcancer i syfte att identifiera venös invasion / Evaluation of three different methods for Van Gieson Elastin staining on Colorectal Cancer in order to identify venous invasionMoradi, Behrouz January 2021 (has links)
Kolorektalcancer är den tredje vanligaste cancerformen hos både män och kvinnor i Sverige där storkärls invasion, venös invasion (VI), är en viktig prognostisk indikator. Noggrann bedömning av VI är särskilt viktigt för patienter med kolorektal cancer i stadium II eftersom det kan påverka beslutet att erbjuda adjuvant behandling. Histologisk bedömning av VI kan vara utmanande på rutinmässig Hematoxylin och Eosin färgning (H&E). Elastinfärgning med syfte att identifiera elastinfibrer i kärlväggen kan underlätta bedömning av VI. I dagsläget finns inte någon bra elastinfärgning som kan användas rutinmässigt hos klinisk patologi i Värmland, Centralsjukhuset Karlstad, prover måste skickas till annat laboratorium vilket är tidskrävande. Denna studie ska finna den optimala färgningsmetoden för elastin genom att utvärdera tre olika färgningsmetoder för elastin fibrer. Färgningens resultat bedömdes rent histokemiskt av överläkare enlig kriterierna, frånvaro av avsedda kärl (skala 0–1), specifik infärgning (skala 0–1), specifik infärgnings intensitet (skala 1–3) och ospecifik infärgning (skala 0–1) och data samlades för respektive metod. Resultatet tyder på att rent histokemiskt är den manuella elastinfärgning metoden från Region Jönköpings län konsekvent och visade signifikant skillnad. Därför metoden är potentiellt användbar för den större frågeställningen om storkärlsinväxt i kolorektal cancer samt rekommenderas starkt som en rutinmässig elastinfärgning till klinisk patologi i Värmland, Centralsjukhuset Karlstad. / The third most common form of cancer in both men and women in Sweden is Colorectal cancer. Prognostic indicators of colorectal cancer include Large vessel invasion and venous invasion (VI). Careful assessment of VI is of particular interest especially with patients having stage II colorectal cancer. This is because it may influence decisions to offer adjuvant therapy. Accurate histological assessment of VI can be challenging on routine hematoxylin and eosin staining. But staining that can identify the elastin fibers in the vessel can enhance the assessment of VI. Currently, there is not any good Elastin staining that can be routinely used in clinical pathology in Värmland, Karlstad Central Hospital. Therefore, samples are required to be sent to other laboratories which in effect is time consuming. This study is aimed at finding an optimal elastin staining method through evaluations of three different staining methods for elastin fibers. Staining results were assessed histochemically by the chief physician according to the following criteria, absence of intended vessels (scale 0–1), specific staining (scale 0–1), specific staining intensity (scale 1–3) and nonspecific staining (scale 0–1), while different data were collected for each method. The results indicate that purely histochemically, elastin staining-manual method Region Jönköping County is consistent and significant. Therefore, the method is potentially useful for the detection of colorectal cancer and is strongly recommended as a routine elastin staining for clinical pathology in Värmland, Karlstad Central Hospital.
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