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Sequential Monte Carlo (SMC) methods are a class of Monte Carlo methods that are used to obtain random samples of a high dimensional random variable in a sequential fashion. Many problems encountered in applications often involve different types of constraints. These constraints can make the problem much more challenging. In this paper, we formulate a general framework of using SMC for constrained sampling problems based on forward and backward pilot resampling strategies. We review some existing methods under the framework and develop several new algorithms. It is noted that all information observed or imposed on the underlying system can be viewed as constraints. Hence the approach outlined in this paper can be useful in many applications.

Estimation of the high-dimensional banded covariance matrix is widely used in multivariate statistical analysis. To ensure the validity of estimation, we aim to test the hypothesis that the covariance matrix is banded with a certain bandwidth under the high-dimensional framework. Though several testing methods have been proposed in the literature, the existing tests are only powerful for some alternatives with certain sparsity levels, whereas they may not be powerful for alternatives with other sparsity structures. The goal of this paper is to propose a new test for the bandedness of high-dimensional covariance matrix, which is powerful for alternatives with various sparsity levels. The proposed new test also be used for testing the banded structure of covariance matrices of error vectors in high-dimensional factor models. Based on these statistics, a consistent bandwidth estimator is also introduced for a banded high dimensional covariance matrix. Extensive simulation studies and an application to a prostate cancer dataset from protein mass spectroscopy are conducted for evaluating the effectiveness of the proposed adaptive tests blue and bandwidth estimator for the banded covariance matrix.

Evidence suggests that emotional distress, including problems like depression and anxiety is commonly reported by individuals meeting criteria for psychosis spectrum disorders. It has been argued that the appraisals individuals hold about the meaning of their psychosis may explain the emotional distress experienced. However, this literature has often failed to acknowledge the role of other variables in accounting for this distress. The aim of this thesis was to investigate the mechanisms underpinning emotional distress in those experiencing psychosis, by focusing specifically on psychosis-related appraisals and goal expectancy. A total of five studies are reported, four of these addressed the above aim by focusing specifically on individuals with a psychosis related disorder who were receiving support from a rehabilitation service. The final study captured how parental carers make sense of their child’s future following an experience of psychosis. Following a review of the literature in Chapter One, Chapter Two aimed to provide an overview of the methodological approaches employed in the current thesis. The study presented in Chapter Three aimed to synthesis the literature investigating the association between appraisals of psychosis experience and emotional distress in those experiencing psychosis, in order to determine the direction and magnitude of this association. A total of 17 studies were included in the review (15 in the meta-analysis). Small to moderate associations were observed between appraisals of psychosis and both depression and anxiety. A narrative synthesis of the literature showed that significant associations were evident in a small number of longitudinal studies (with regards to depression only). Furthermore, i in a number of cross-sectional studies significant associations held even when accounting for symptoms of psychosis, suggesting that the association that beliefs have with distress may not be entirely explained by the shared association with psychosis symptom severity. Chapter Four presents the findings of a study that aimed to validate a goal generation task within individuals experiencing psychosis. Using behaviour sequence analysis, the utility of the task in capturing goal generation processes in those meeting criteria for psychosis was determined. The study highlighted that those experiencing psychosis were able to progress from lower to higher-order goals. Using a cross-sectional design, Chapter Five aimed to investigate the extent to which psychosis related appraisals and goal expectancies (goal likelihood and goal difficulty) could account for emotional distress in those experiencing psychosis. A total of 73 individuals accessing support from a rehabilitation service were recruited. Results revealed that appraisals of psychosis were significantly associated with depression and anxiety. Specifically, appraisals of psychosis as a source of internal shame and defectiveness, external shame and as resulting in loss (e.g., loss of future employments) were all found to predict both depression and anxiety. Many of these associations held when controlling for other variables. Only appraisals of internal shame and defectiveness were found to be significantly associated with emotional distress, however, this association did not hold when controlling for other variables. When adjusting for appraisals of psychosis, goal appraisals were not found to be significantly associated with emotional distress. Chapter Six aimed to expand upon the results presented in chapter five by investigating the longitudinal association between goal expectancies (goal likelihood, difficulty and progress) and emotional distress. A series of mixed model ii regression analyses were carried out to determine the concurrent association between the variable and to establish if the degree of change in goal appraisals would correspond with changes in depression scores. On the whole these models revealed that goal expectancies do not have a consistent association with emotional distress when adjusting for other factors. However, they did highlight that appraisals of psychosis may be implicated in emotional distress within individuals experiencing psychosis. Finally, Chapter Seven presents the findings of a qualitative paper. Nine parental carers were interviewed with the aim of exploring how they make sense of their child’s future following an experience of psychosis, focusing particularly on the goals and aspirations parental carers hold for their adult children. An interpretative phenomenological analysis was carried out. A total of three superordinate themes emerged, impact of psychosis (subthemes: psychosis causing a change of path, goals: lost, maintained and adjusted), a fear of relapse (subthemes: concerns about coping and adjustment), and navigating the future (subthemes: hope, uncertainty and somewhere in between, barriers and facilitators). Overall, the findings from the current thesis suggest that appraisals of psychosis experience are important in accounting for emotional distress, an effect that was observed consistently across the studies reported within this thesis. However, it appears that goal expectancies do not have a consistent effect with emotional distress.

This paper aims to test the number of spikes in a generalized spiked covariance matrix, the spiked eigenvalues of which may be extremely larger or smaller than the non-spiked ones. For a high-dimensional problem, we first propose a general test statistic and derive its central limit theorem by random matrix theory without a Gaussian population constraint. We then apply the result to estimate the noise variance and test the equality of the smallest roots in generalized spiked models. Simulation studies showed that the proposed test method was correctly sized, and the power outcomes showed the robustness of our statistic to deviations from a Gaussian population. Moreover, our estimator of the noise variance resulted in much smaller mean absolute errors and mean squared errors than existing methods. In contrast to previously developed methods, we eliminated the strict conditions of diagonal or block-wise diagonal form of the population covariance matrix and extend the work to a wider range without the assumption of normality. Thus, the proposed method is more suitable for real problems., 23 pages,3 figures

The goal of this study is to review the overall prevalence, burden, and distribution of the dengue disease in Pakistan from 2000 to 2019. Literature was searched using different search engines like Google scholar, PubMed, etc. providing the keywords “Dengue disease/infection, Dengue virus, DENV, DF/DHF/ DSS Pakistan”. All the published research papers/reports on the dengue virus over the period 2000 to 2019 were studied and selected data were summarized using MS Excel for windows such as total cases, age wise, gender, DENV serotype distribution, total DHF, and DSS patients. The literature providing insufficient data was excluded. The total number of cases reported during 2000-19 were 201,269. The maximum number of cases during the mentioned literature survey period was reported in Khyber Pakhtunkhwa (KP) (23.3%) followed by Punjab (3.8%) and Sindh (1.9%). The majority of dengue-infected cases were reported as Dengue fever (74.4%) followed by DHF (24.1%) and DSS (1.5%). Overall the deaths during the mentioned literature survey were 1082, of which the maximum mortalities were reported from KP (N=248) followed by Punjab (N=220). DENV remains a major public health problem in Pakistan and seems to remain endemic for a long time. The total prevalence of dengue infection is increased accordingly with time from 2000 to 2019. Moreover, all the four serotypes exist in Pakistan with increased mortalities.

A composite likelihood is a combination of low-dimensional likelihood objects useful in applications where the data have complex structure. Although composite likelihood construction is a crucial aspect influencing both computing and statistical properties of the resulting estimator, currently there does not seem to exist a universal rule to combine low-dimensional likelihood objects that is statistically justified and fast in execution. This paper develops a methodology to select and combine the most informative low-dimensional likelihoods from a large set of candidates while carrying out parameter estimation. The new procedure minimizes the distance between composite likelihood and full likelihood scores subject to a constraint representing the afforded computing cost. The selected composite likelihood is sparse in the sense that it contains a relatively small number of informative sub-likelihoods while the noisy terms are dropped. The resulting estimator is found to have asymptotic variance close to that of the minimum-variance estimator constructed using all the low-dimensional likelihoods.

In this paper, we propose a new spectral-based approach to hypothesis testing for populations of networks. The primary goal is to develop a test to determine whether two given samples of networks come from the same random model or distribution. Our test statistic is based on the trace of the third order for a centered and scaled adjacency matrix, which we prove converges to the standard normal distribution as the number of nodes tends to infinity. The asymptotic power guarantee of the test is also provided. The proper interplay between the number of networks and the number of nodes for each network is explored in characterizing the theoretical properties of the proposed testing statistics. Our tests are applicable to both binary and weighted networks, operate under a very general framework where the networks are allowed to be large and sparse, and can be extended to multiple-sample testing. We provide an extensive simulation study to demonstrate the superior performance of our test over existing methods and apply our test to three real datasets.

Treball acceptat per publicar al proper volum 65 de la revista "Onomázein : Revista de Lingüística, Filología y Traducción" al tercer trimestre de 2024. Desde la campaña de Reforma y apertura iniciada en China en 1978, se ha despertado en este país el interés por la poesía española y han sido publicadas numerosas antologías poéticas. Sin embargo, la poesía femenina, muy destacable en el conjunto de la producción poética española, no había sido recopilada de manera sistemática hasta la publicación en 2001 de Antología de la poesía femenina española del siglo XX, obra del traductor Zhao Zhenjiang. El presente artículo se centra en cinco poetas españolas de la Generación del 27 incluidas en dicha antología y analiza las normas y las técnicas aplicadas en el proceso traductor. Since China's economic reform in 1978, people's interest in Spanish poetry has begun to awake and a large number of anthologies of poems have been published. However, female poetry, which has attracted worldwide attention in Spanish poetry creation, was not systematically compiled until 2001 when the translator Zhao Zhenjiang's Anthology of Spanish Female Poetry in the 20th Century was published. This paper focuses on five Spanish poetesses of the 27 Generation included in this collection of poems, and analyzes the principles and techniques used in the process of translation

In this paper, we provide an overview of the evolution of the definition of hyperglycemia during the past century and the alterations in glucose dynamics that cause fasting and postprandial hyperglycemia. We discuss how extensive mechanistic, physiological research into the factors and pathways that regulate the appearance of glucose in the circulation and its uptake and metabolism by tissues and organs has contributed knowledge that has advanced our understanding of different types of hyperglycemia, namely prediabetes and diabetes and their subtypes (impaired fasting plasma glucose, impaired glucose tolerance, combined impaired fasting plasma glucose, impaired glucose tolerance, type 1 diabetes, type 2 diabetes, gestational diabetes mellitus), their relationships with medical complications, and how to prevent and treat hyperglycemia.

Selecting hyperparameters for unsupervised learning problems is challenging in general due to the lack of ground truth for validation. Despite the prevalence of this issue in statistics and machine learning, especially in clustering problems, there are not many methods for tuning these hyperparameters with theoretical guarantees. In this paper, we provide a framework with provable guarantees for selecting hyperparameters in a number of distinct models. We consider both the subgaussian mixture model and network models to serve as examples of i.i.d. and non-i.i.d. data. We demonstrate that the same framework can be used to choose the Lagrange multipliers of penalty terms in semi-definite programming (SDP) relaxations for community detection, and the bandwidth parameter for constructing kernel similarity matrices for spectral clustering. By incorporating a cross-validation procedure, we show the framework can also do consistent model selection for network models. Using a variety of simulated and real data examples, we show that our framework outperforms other widely used tuning procedures in a broad range of parameter settings.

Abstract This paper studied the behavior of multidimensional and income poverty, as well as its determinants in Brazil, in addition to rural and urban areas, based on information from the 2019 National Continuous Household Sample Survey (PNADC). The Alkire-Foster methodology was used in the construction of a Multidimensional Poverty Index (MPI), in addition to the logit model to estimate the impacts of determinants related to household characteristics on poverty. The health and sanitation dimension was the one that contributed the most to the MPI, followed by the education and housing dimensions. Unidimensional poverty was greater than multidimensional and rural poverty was also greater. Among the determinants of poverty, being in households with non-white heads, younger, unmarried, unemployed, less educated and in the North and Northeast regions increased the chances of poverty. In addition, while female heads reduced the chances of multidimensional poverty, it increased the chances of the unidimensional one.

This paper projects and analyzes the regional impacts of climate change on the agricultural productivity of family farming and large-scale agriculture in Brazil between 2021 and 2050, using the RCP 4.5 and RCP 8.5 scenarios. The methodology adopted consists of a cross-sectional estimation of a production function in which agricultural productivity is determined by climatic, geographic, and productive factors. The study contributes to the literature by disaggregating agricultural production into family farming and large-scale agriculture, indicating the magnitude and direction of impacts by crops and regions in Brazil, a country with a great territorial dimension and relevant and heterogeneous agricultural production. The results indicate that the agricultural productivity of family farming is more sensitive and therefore this type of producer could be more vulnerable to the phenomenon. On average, the effects will be negative in the North/Northeast regions and for cassava, maize, beans, and soybeans, with possible impacts on deforestation and on food supply. Productivity gains are expected in the southern region and for the cultivation of sugar cane and soybeans. Deterioration of food security of the vulnerable farmers and regional disparities may increase in Brazil.

High-dimensional self-exciting point processes have been widely used in many application areas to model discrete event data in which past and current events affect the likelihood of future events. In this paper, we are concerned with detecting abrupt changes of the coefficient matrices in discrete-time high-dimensional self-exciting Poisson processes, which have yet to be studied in the existing literature due to both theoretical and computational challenges rooted in the non-stationary and high-dimensional nature of the underlying process. We propose a penalized dynamic programming approach which is supported by a theoretical rate analysis and numerical evidence.

This thesis presents a critical examination of the rivalry between G. W. M. Reynolds and Charles Dickens between 1837 and 1870. Specifically, the thesis analyses three distinct phases of their rivalry. The first is its inception in 1837 following Reynolds���s publication of Pickwick Abroad, his ���sequel��� to Dickens���s Pickwick Papers (1836). The second phase concerns the 1840s, examining how Reynolds���s success and reputation directly impacted upon Dickens���s position in the literary market. The final phase addresses the most explicit and combative chapter of their rivalry as the two traded insults across their publications in the 1850s and Dickens looked to ���displace��� his more radical counterpart. Commonly cited as a peripheral figure in Dickens���s career, this thesis argues for Reynolds as a more significant presence. By analysing their publications in parallel, often viewing one through the lens of the other, this study offers a fresh perspective on two authors competing for readerships and commercial marketspace while grappling with authorial identities in the first age of mass culture. The thesis presents three principal arguments. Firstly, it seeks to contest the reductive perception of Reynolds as a cheap plagiariser of Dickens���s work by analysing the more nuanced and complex aspects of Reynolds���s early re-appropriations. Secondly, it argues that Reynolds���s precipitous rise to literary fame and political notoriety after 1844 had a significant bearing on the fiction Dickens produced thereafter. It is contended that Dickens���s abrupt shift from the political incendiarism of The Chimes in 1844 into a ���transitional period��� in 1845, after which his fiction became more domestically, or family-oriented, can be understood as a response, or reaction to Reynolds���s concurrent literary successes and his growing reputation as a radical and political subversive. Finally, it is reasoned that the bitter exchange of insults between Dickens and Reynolds in the 1850s and the seemingly mutable tone of their rivalry up until Dickens���s death in 1870 illustrates a relationship not entirely the product of natural antipathy, but one cultivated for commercial and political purposes. It is argued that both Dickens and Reynolds constructed an image of the other in order to mask their similarities and natural affinities and to bolster and better define their own position in the literary marketplace.

The new identifiable case appeared in \cite{AGMO}, together with the analysis on simultaneous identifiability of pairs of ternary forms recently developed in \cite{BG}, suggested the following conjecture towards a complete classification of all simultaneous Waring identifiable cases: for any $ d \geq 2 $, the general polynomial vectors consisting of $ d-1 $ ternary forms of degree $ d $ and a ternary form of degree $ d+1 $, with rank $ \frac{d^2+d+2}{2} $, are identifiable over $ \mathbf{C} $. In this paper, by means of a computer-aided procedure inspired to the one described in \cite{AGMO}, we obtain that the case $ d = 4 $ contradicts the previous conjecture, admitting at least $ 36 $ complex simultaneous Waring decompositions (of length $ 11 $) instead of $ 1 $., Comment: 10 pages, accepted for publication on Journal of Symbolic Computation

Recently, thinning an antenna has resulted in attractive antenna radiation characteristics enhancement. This performance enhancement using a thin antenna array is achieved because the inter-coupling effects of the array elements are reduced. Though the thinning both reduces the weight of the antenna and enhances the radiation characteristics, iterative algorithms can further enhance the performance and hence, in this research, an optimizer algorithm and inter-coupling reducing mechanisms are applied. The excitation weights of the individual array elements are thinned by turning some of the elements off while some of the elements are turned on. The purpose of the thinning is to enhance the antenna performances like reduced SLL, high directivity, reduced power consumption and flexible radiation pattern. The SLL attenuation mechanism is applied to reduce the SLL in addition to the SLL reduction using the thinning and beamforming. Hence, in this paper, the three techniques (thinning, beamforming and SLL attenuation) are proposed to be integrated to enhance the antenna radiation characteristics. In general, the proposed combined method has resulted in much better SLL reduction, directivity improvement, and power wastage reduction.