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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

The Effects of the Ratio of Utilized Predictors to Original Predictors on the Shrinkage of Multiple Correlation Coefficients

Petcharat, Prataung Parn 08 1900 (has links)
This study dealt with shrinkage in multiple correlation coefficients computed for sample data when these coefficients are compared to the multiple correlation coefficients for populations and the effect of the ratio of utilized predictors to original predictors on the shrinkage in R square. The study sought to provide the rationale for selection of the shrinkage formula when the correlations between the predictors and the criterion are known and determine which of the three shrinkage formulas (Browne, Darlington, or Wherry) will yield the R square from sample data that is closest to the R square for the population data.
2

Task Persistence in Early Childhood Education

Stephenson, Thomas Richard 01 May 1973 (has links)
This study was designed to discover developmental trends in task persistence (TP). It was hoped that the results would suggest when and for what groups a task persistence (TP) curriculum is crucial. To study this development a sample of two, four, and six year old children were given a "work" task. The task required 120 subjects (Ss) to sort and fold 33 items of clothing and linen. After the task instructions and demonstration, the experimenter did not intervene with reinforcers or further directions. The dependent variables investigated were time spent on the task, time spent away from the task, and number of tasks completed. The independent variables were age, race (Black and White), sex, and social class (advantaged and disadvantaged). The data were analyzed with analysis of variance, Pearson's Product-Moment Correlation, and chi square. The results indicated that older children spent significantly more time on task and significantly less time away from task than younger children. Black children spent significantly more time (than White children) on and away from the task at all ages. Advantaged children spent significantly more time (than disadvantaged children) on task at all ages and significantly less time away from task at ages two and four. Advantaged and disadvantaged subjects were not differentiated by the time spent away from the task at age six. These results imply that task persistence training programs could begin as early as age two. They also suggest that certain subgroups (i.e., disadvantaged White) may require more intensive task persistence training then other subgroups (i.e., advantaged Black). Completion of tasks (CT) significantly differentiated six year olds from two and four year olds, but failed to differentiate two and four year olds. Tasks were completed significantly more often at ages two and four by males than females and by advantaged than disadvantaged children. However, these differences disappeared by age six. Since the differences faded at age six, the use of completion of tasks training as a general curriculum goal may not be warranted. Some of the most surprising results were described by the significant correlation coefficients. The total time spent on the task was negatively related to completion of task. Completion of task was positively related to the time spent away from the task and number of times away from task. These findings suggest that brief periods of absence from a task may improve the chances of completing the task. Therefore, optimal "work" performance for early childhood education may be realized by programming frequent, brief "breaks." A secondary purpose of the study was to investigate verbalizations expressed during the experimental sessions. To study this variable, a verbatim record was established and maintained for each subject. The verbalizations were then totaled and classified as task relevant or irrelevant. The results were analyzed with an analysis of variance (age x race x sex x social class) and Pearson's Product Moment Correlation. Although the number of verbalizations increased with age, the differences between ages four and six were not significant. This finding may reflect a shift to covert verbal mediation during "work" performance on or about age four. The developmental patterns of verbalizations were different for boys and girls. The girls used more overt verbalizations (than boys) at ages two and four; however, at age six the girls' number of verbalizations decreased noticeably. The verbalizations of boys increased with age. At age six, they used more verbalizations than the girls. The writer concluded that this finding reflected advanced verbalization skills in the girls. If the conclusion is valid, the results may mean that overt verbalizations are more necessary for boys to organize their experiences. White children used significantly more task relevant verbalizations than Black children. This suggests that early childhood educational programs for predominately Black populations may need to stress task relevant verbalization training more than programs which serve predominately White populations. Disadvantaged children used more task irrelevant verbalizations at ages two and six than advantaged children. Apparently, they need extra emphasis on task oriented verbalization training. When considered with the previous paragraph, the disadvantaged Black population has the greatest need for task relevant verbalization training.
3

Method for Identifying Resting State Networks following Probabilistic Independent Component Analysis

Drake, David M. January 2014 (has links)
No description available.
4

Analysis of the Total Food Folate Intake Data from the National Health and Nutrition Exa-amination Survey (Nhanes) Using Generalized Linear Model

Lee, Kyung Ah 01 December 2009 (has links)
The National health and nutrition examination survey (NHANES) is a respected nation-wide program in charge of assessing the health and nutritional status of adults and children in United States. Recent cal research found that folic acid play an important role in preventing baby birth defects. In this paper, we use the generalized estimating equation (GEE) method to study the generalized linear model (GLM) with compound symmetric correlation matrix for the NHANES data and investigate significant factors to ence the intake of food folic acid.
5

Verificação de assinaturas off-line utilizando o coeficiente de correlação de Pearson

Clerot, Davi Delgado 28 April 2014 (has links)
Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2016-06-13T13:50:41Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação - Davi Delgado Clerot - UFPE.pdf: 1275511 bytes, checksum: 8413259c0fde19c85569221d062625a8 (MD5) / Made available in DSpace on 2016-06-13T13:50:41Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação - Davi Delgado Clerot - UFPE.pdf: 1275511 bytes, checksum: 8413259c0fde19c85569221d062625a8 (MD5) Previous issue date: 2014-04-28 / No âmbito da biometria comportamental, o reconhecimento automático de assinaturas manuscritas off-line se destaca pela boa aceitação em diversos segmentos, tais como Bancos, Cartórios e Imobiliárias. Dentre os fatores que estimulam sua utilização estão a facilidade na aquisição, pois não depende de equipamentos específicos, e seu valor legal ao ser realizada de próprio punho. No intuito de investigar métodos alternativos para realizar sua verificação automática, esta dissertação testa uma abordagem baseada no Coeficiente de Correlação de Pearson. O experimento foi realizado em seis etapas; da primeira à terceira, são utilizadas variações na extração de características, sem o auxílio de um classificador baseado em aprendizado automático. No quarto experimento, foi utilizada uma rede neural artificial como classificador, para efeito de comparação com os resultados anteriores. No quinto experimento, um peso associado ao limiar de resposta utilizado nos experimentos anteriores foi adicionado objetivando minimizar efeitos dos falsos positivos obtidos. No sexto e último experimento, para efeito de comparação com trabalhos relacionados, foi utilizada a base de dados disponibilizada no ICDAR (Conferência Internacional em Reconhecimento e Análise de Documentos) 2011. A configuração empregada nesta etapa, a qual utilizou a base do ICDAR, foi a do melhor experimento realizado dentre os anteriores. Os métodos propostos apresentaram resultados promissores em comparação com os resultados apresentados na literatura. / In the field of behavioral biometrics, automatic off-line handwritten signature recognition stands out for its widespread acceptance in different market segments, such as Banks, Civil Registry Offices and Real State Agencies. Among the reasons why its use is widely stimulated are its ease of acquisition, once it does not depend on specific equipment, and its legal value when it is done by the author’s own handwriting. With the purpose of searching for alternative methods to proceed to its automatic verification, this essay tests out an approach based on Pearson Correlation Coefficient. The experiment was carried out through six steps; from the first to the third ones, there were used variations for feature extraction, without the assistance of a learning classifier. In the fourth experiment, there was used an artificial neural network as a classifier, in order to compare its results with those obtained in the previous tests. In the fifth experiment, a weight associated to the threshold results obtained in the previous experiments was added, so as to minimize the false positive rate. In the sixth and last experiment, for comparison with related essays, there was used the ICDAR (International Conference on Document Analysis and Recognition) 2011 database. The configuration utilized in this last step was the one obtained in the best test among the previous ones. The proposed methods presented promising results compared to others reported in the literature.
6

Estudo de coeficientes de correlação para medidas de proximidade em dados de expressão gênica / A study of correlation coefficients as proximity measures for gene expression data

Jaskowiak, Pablo Andretta 02 March 2011 (has links)
O desenvolvimento da tecnologia de microarray tornou possível a mediçao dos níveis de expressão de centenas ou até mesmo milhares de genes simultaneamente para diversas condições experimentais. A grande quantidade de dados disponível gerou a demanda por métodos computacionais que permitam sua análise de forma eficiente e automatizada. Em muitos dos métodos computacionais empregados durante a análise de dados de expressão gênica é necessária a escolha de uma medida de proximidade apropriada entre genes ou amostras. Dentre as medidas de proximidade disponíveis, coeficientes de correlação têm sido amplamente empregados, em virtude da sua capacidade em capturar similaridades entre tendências das sequências numéricas comparadas (genes ou amostras). O presente trabalho possui como objetivo comparar diferentes medidas de correlação para as três principais tarefas envolvidas na análise de dados de expressão gênica: agrupamento, seleção de atributos e classificação. Dessa forma, é apresentada nesta dissertação uma visão geral da análise de dados de expressão gênica e das diferentes medidas de correlação consideradas para tal comparação. São apresentados também resultados empíricos obtidos a partir da comparação dos coeficientes de correlação para agrupamento de genes, agrupamento de amostras, seleção de genes para o problema de classificação de amostras e classificação de amostras / The development of microarray technology made possible the expression level measurement of hundreds or even thousands of genes simultaneously for various experimental conditions. The huge amount of available data generated the need for computational methods that allow its analysis in an effcient and automated way. In many of the computational methods employed during gene expression data analysis the choice of a proximity measure is necessary. Among the proximity measures available, correlation coefficients have been widely employed because of their ability to capture similarity trends among the compared numeric sequences (genes or samples). The present work has as objective to compare different correlation measures for the three major tasks involved in the analysis of gene expression data: clustering, feature selection and classification. To this extent, in this dissertation an overview of gene expression data analysis and the different correlation measures considered for this comparison are presented. In the present work are also presented empirical results obtained from the comparison of correlation coefficients for gene clustering, sample clustering, gene selection for sample classification and sample classification
7

Estudo de coeficientes de correlação para medidas de proximidade em dados de expressão gênica / A study of correlation coefficients as proximity measures for gene expression data

Pablo Andretta Jaskowiak 02 March 2011 (has links)
O desenvolvimento da tecnologia de microarray tornou possível a mediçao dos níveis de expressão de centenas ou até mesmo milhares de genes simultaneamente para diversas condições experimentais. A grande quantidade de dados disponível gerou a demanda por métodos computacionais que permitam sua análise de forma eficiente e automatizada. Em muitos dos métodos computacionais empregados durante a análise de dados de expressão gênica é necessária a escolha de uma medida de proximidade apropriada entre genes ou amostras. Dentre as medidas de proximidade disponíveis, coeficientes de correlação têm sido amplamente empregados, em virtude da sua capacidade em capturar similaridades entre tendências das sequências numéricas comparadas (genes ou amostras). O presente trabalho possui como objetivo comparar diferentes medidas de correlação para as três principais tarefas envolvidas na análise de dados de expressão gênica: agrupamento, seleção de atributos e classificação. Dessa forma, é apresentada nesta dissertação uma visão geral da análise de dados de expressão gênica e das diferentes medidas de correlação consideradas para tal comparação. São apresentados também resultados empíricos obtidos a partir da comparação dos coeficientes de correlação para agrupamento de genes, agrupamento de amostras, seleção de genes para o problema de classificação de amostras e classificação de amostras / The development of microarray technology made possible the expression level measurement of hundreds or even thousands of genes simultaneously for various experimental conditions. The huge amount of available data generated the need for computational methods that allow its analysis in an effcient and automated way. In many of the computational methods employed during gene expression data analysis the choice of a proximity measure is necessary. Among the proximity measures available, correlation coefficients have been widely employed because of their ability to capture similarity trends among the compared numeric sequences (genes or samples). The present work has as objective to compare different correlation measures for the three major tasks involved in the analysis of gene expression data: clustering, feature selection and classification. To this extent, in this dissertation an overview of gene expression data analysis and the different correlation measures considered for this comparison are presented. In the present work are also presented empirical results obtained from the comparison of correlation coefficients for gene clustering, sample clustering, gene selection for sample classification and sample classification
8

Reprezentace států v sekretariátu Světové zdravotnické organizace / Countries' Representation in Professional Staff of the World Health Organization

Slámková, Eliška January 2021 (has links)
My thesis is focused on the composition and countries' representation in the professional staff of the World Health Organization. The thesis will analyse the overrepresentation and underrepresentation of the WHO's member states and explain possible patterns in the staff. The thesis will focus on the relationship between the number of Member State's professional staff in the WHO and the state's GDP growth, expenditure on education and population size. My thesis aims to research the characteristics of staff's composition in the WHO. I will analyse professional staff structure and apply the Principal-Agent theoretical framework. The research will show how the state's representation of member states changed over time and see also the gender composition of the Secretariat. The timeline of this work is from 1999 till 2019. The thesis works with official documents from human resources of the WHO and datasets of the World Bank. Analysis of data is provided by the statistical programme SPSS and Microsoft Excel. Key words World Health Organization, representation, professional staff, principal-agent theory, correlation coefficients, regression analysis
9

ENHANCED PRODUCTION PLANNING AND SCHEDULING METHOD FOR CONSTRUCTION PROJECTS

Qais Amarkhil (6616994) 05 July 2022 (has links)
<p>  </p> <p>Available literature indicated that construction projects have been experiencing significant time overruns from their planned duration. In many cases, the primary reasons for project delays were ineffective planning and scheduling methods, poor communication and collaboration between the key stakeholders, and the construction operations and task requirements have been overlooked.</p> <p>Construction project planning and scheduling are extensively studied topics, and several techniques have been developed to solve construction project scheduling problems. Traditional production planning and scheduling techniques are based on the push planning strategy, such as linear and network scheduling techniques. In the traditional method, the project scheduler calculates activity durations and then sequences them to determine when to complete the work. These techniques and planning methods have been criticized for lacking collaboration between project workers and realistic integration of the project time, location, and other essential resources to create a reliable work schedule. Furthermore, the inability to account for site operations, tasks, and workflow leads to waste and delay. </p> <p>Consequently, Ballard and Howell (1990) proposed the last planner system, and then Ballard et al. (2000) further developed the method. In the last planner system, all key stakeholders and the project management team actively communicate and coordinate to accomplish the project’s planned milestones. The last planner system and pull planning scheduling objective is improving workflow and increasing plan reliability. However, the pull planning scheduling method has some limitations. For instance, this method cannot be used to determine the available work capacity in each working space and show how much work can be completed at a given time. In addition, the pull planning and LPS system are highly descriptive and experienced-based, relying on the decision and experiences of the site supervisors. </p> <p>Available literature concerning construction project delay also indicated that ineffective planning and scheduling, slow decision-making, and poor communication and coordination had been the top critical causes of construction project delay.</p> <p>Therefore, this research was conducted to minimize construction project time and cost overrun due to poor scheduling and production planning. The study has been conducted in two main parts. In the first part of this study, critical causes of project delay have been analyzed, and the contribution of poor planning and scheduling to construction project delays in different environments has been assessed. The relative importance index and Spearman’s coefficient techniques have been utilized to analyze the collected data.  The second section of this research work was conducted to investigate the construction scheduling reliability and production efficiency and developed the enhanced production planning and scheduling method to improve schedule reliability and production plan efficiency.  The reason for developing the enhanced production planning and scheduling method was to find the best work option to optimize work duration and efficiently plan required resources per category of the identified activities. In addition, this study has automated the scheduling input data capturing from the project BIM model by utilizing the developed visual program.</p> <p>The study finding in the first section indicated that the top ten critical causes of identified causes of project delay in specified environments were significantly different. However, Ineffective project planning and scheduling had been among the most critical causes in all three conditions. Ineffective planning and scheduling were ranked number one in developed environment conditions, second in developing countries, and fifth in high-risk environments.</p> <p>Study results in the second section have shown that the case study's executed schedule had experienced significant changes in the planned dates of individual tasks, project milestones, and resource allocation. The project schedule critical path and critical activities were changed repeatedly after each update, and the project structure work was delayed for 30 days from its initial plan, as illustrated in figures 33 to 35. Subsequently, the enhanced planning methodology has been applied in the selected case study to validate the developed method and evaluate the result of the case study. The case study implemented work plan has been compared with the enhanced planning-based developed schedule. The total duration of the enhanced planning-based method has been calculated to be 240 work days, which shows 30 days less time from implemented case study plan and 50 days from the project base plan in the construction document, as illustrated in figures 39 to 41. </p> <p>Furthermore, the production schedule sensitivity analysis has shown that the production schedule and the case study base plan tasks duration have not been significantly different since both schedules were created based on the similar size of the work crew, but in terms of the number of the planned task, the production schedule had been created based on the most suitable work option. Another advantage of the production schedule is that it is more reliable because the schedule is created for a shorter duration, not long before the project work starts, and it is created after multiple collaborations and assessment steps. In addition, the developed program in this study using Revit dynamo automated the extraction of input data from the BIM model to create the project schedule. </p> <p>In conclusion, based on the case study results, the enhanced production planning methodology and developed metrics and indices can be applied to various building construction projects to find the most suitable work option and create a reliable and resource-efficient work schedule. </p>
10

Mainland Canadian English in Newfoundland

Hofmann, Matthias 06 July 2015 (has links) (PDF)
The variety of middle-class speakers in St. John’s conforms to some degree to mainland Canadian-English pronunciation norms, but in complex and distinctive ways (Clarke, 1985, 1991, 2010; D’Arcy, 2005; Hollett, 2006). One as yet unresolved question is whether speakers of this variety participate in the Canadian Shift (cf. Clarke, 2012; Chambers, 2012), a chain shift of the lax front vowels that has been confirmed for many different regions of Canada (e.g. Roeder and Gardner, 2013, for Thunder Bay and Toronto, Sadlier-Brown and Tamminga, 2008, for Halifax and Vancouver). While acoustic phonetic analyses of St. John’s English are rare, some claims have been made that urban St. John’s speakers do not participate in the shift, based on two or six speakers (Labov, Ash & Boberg, 2006; Boberg 2010). Other researchers with larger data sets suggest that younger St. John’s speakers participate in mainland Canadians innovations to different degrees than mainlanders (e.g. Hollett, 2006). The Canadian Shift has not been uniformly defined, but agreement exists that with the low-back merger in place, BATH/TRAP retracts and consequently DRESS lowers. Clarke et al. (1995), unlike Labov et al. (2006), assert that KIT is subsequently lowered. Boberg (2005, 2010), however, emphasizes retraction of KIT and DRESS and suggests unrelated parallel shifts instead. In this PhD thesis, I demonstrate the presence of the Canadian Shift in St. John’s, NL, conforming to Clarke et al.’s (1995) original proposal. In my stratified randomly-sampled data (approx. 10,000 vowels, 34 interviewees, stratified as to age, gender, socioeconomic status, and “local-ness”), results from Euclidean distance measures, correlation coefficients, and linear, as well as logistic, mixed-effects regression show that (1) young St. John’s speakers clearly participate in the shift; and that (2) age has the strongest and a linear effect. Continuous modeling of age yields even more significant results for participation in a classic chain shift (6% decrease in lowering per added year). My findings also confirm that the change seems to have entered the system via formal styles (cf. Clarke, 1991, 2010, for TRAP in St. John’s). Traditionally, the linguistic homogeneity on a phonetic level of the Canadian middle class has been explained by Canada’s settlement and migration patterns of the North American Loyalists from Ontario to the west (cf. Chambers, 2009). Newfoundland’s settlement is distinct, in that the British and the Irish were the only two relevant sources. If settlement were the only crucial reason for a shared pronunciation of Canada’s middle class from Vancouver to St. John’s, the Canadian Shift should be absent in the latter region. I suggest three reasons for middle-class St. John’s’ participation in the Canadian Shift: 1) Newfoundland’s 300-year-old rural-urban divide as a result of its isolation, through which British/Irish features are attributed to rural und lower social class speakers; 2) the development of the oil industry since the 1990’s, through which social networks changed according to the perception of social distance/closeness; and 3) the importance of the linguistic marketplace, which is high in St. John’s due to 1) and 2).

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