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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.
121

An Analysis of Race and Gender in Select Choice Programs Within Brevard County Public Schools

Doaks, Synthia 01 January 2014 (has links)
The focus of this research was to compare the student membership population proportions, by race and gender, of Brevard County Public School students with the actual participation in select choice programs offered to Brevard County public high school students. This study was based on an analysis of the scores of 1,152 eighth-grade students who received a score of 4 or 5 on the 2008 Florida Comprehensive Assessment Test (FCAT) mathematics and a score of 4 or 5 on the 2008 Florida Comprehensive Assessment Test (FCAT) reading and their participation in high school advanced academic courses. The advanced academic choice programs selected for this study consisted of the four Florida articulated accelerated college credit seeking programs: Advanced Placement (AP), Dual-Enrollment (DE), International Baccalaureate (IB) Diploma Programme, and the Cambridge Advanced International Certificate of Education (AICE). The proportion comparison consisted of student membership data and eighth-grade FCAT scores from 2007-2008 and the student membership data and high school course load data from the 2008-2009, 2009-2010, 2010-2011, and 2011-2012 academic school years. Chi-square goodness-of-fit tests were run to analyze the proportions by race and gender of the sample groups and student membership populations. For each respective year involved in this study, there was a statistically significant difference in the race and gender proportions of the samples and the student membership populations.
122

AN EXAMINATION OF THE RELATIONSHIP BETWEEN PERSONALITY TYPE, SELF PERCEPTION ACCURACY AND TRANSFORMATIONAL LEADERSHIP PRACTICES OF FEMALE HOSPITAL LEADERS

Carroll, Gretchen Kay 10 November 2010 (has links)
No description available.
123

CURE RATE AND DESTRUCTIVE CURE RATE MODELS UNDER PROPORTIONAL ODDS LIFETIME DISTRIBUTIONS

FENG, TIAN January 2019 (has links)
Cure rate models, introduced by Boag (1949), are very commonly used while modelling lifetime data involving long time survivors. Applications of cure rate models can be seen in biomedical science, industrial reliability, finance, manufacturing, demography and criminology. In this thesis, cure rate models are discussed under a competing cause scenario, with the assumption of proportional odds (PO) lifetime distributions for the susceptibles, and statistical inferential methods are then developed based on right-censored data. In Chapter 2, a flexible cure rate model is discussed by assuming the number of competing causes for the event of interest following the Conway-Maxwell (COM) Poisson distribution, and their corresponding lifetimes of non-cured or susceptible individuals can be described by PO model. This provides a natural extension of the work of Gu et al. (2011) who had considered a geometric number of competing causes. Under right censoring, maximum likelihood estimators (MLEs) are obtained by the use of expectation-maximization (EM) algorithm. An extensive Monte Carlo simulation study is carried out for various scenarios, and model discrimination between some well-known cure models like geometric, Poisson and Bernoulli is also examined. The goodness-of-fit and model diagnostics of the model are also discussed. A cutaneous melanoma dataset example is used to illustrate the models as well as the inferential methods. Next, in Chapter 3, the destructive cure rate models, introduced by Rodrigues et al. (2011), are discussed under the PO assumption. Here, the initial number of competing causes is modelled by a weighted Poisson distribution with special focus on exponentially weighted Poisson, length-biased Poisson and negative binomial distributions. Then, a damage distribution is introduced for the number of initial causes which do not get destroyed. An EM-type algorithm for computing the MLEs is developed. An extensive simulation study is carried out for various scenarios, and model discrimination between the three weighted Poisson distributions is also examined. All the models and methods of estimation are evaluated through a simulation study. A cutaneous melanoma dataset example is used to illustrate the models as well as the inferential methods. In Chapter 4, frailty cure rate models are discussed under a gamma frailty wherein the initial number of competing causes is described by a Conway-Maxwell (COM) Poisson distribution in which the lifetimes of non-cured individuals can be described by PO model. The detailed steps of the EM algorithm are then developed for this model and an extensive simulation study is carried out to evaluate the performance of the proposed model and the estimation method. A cutaneous melanoma dataset as well as a simulated data are used for illustrative purposes. Finally, Chapter 5 outlines the work carried out in the thesis and also suggests some problems of further research interest. / Thesis / Doctor of Philosophy (PhD)
124

THE RELATIONSHIP BETWEEN SELF-DETERMINATION AND CLIENT OUTCOMES AMONG THE HOMELESS

Hanna, Samuel M. 01 June 2015 (has links)
This paper has attempted to determine if there is a significant relationship between self-determination and client outcomes among the homeless. The study has been based upon the conceptual framework set forth in Self-Determination Theory. The purpose of the study was to explore the relationship between self-determination and client outcomes among the homeless. Using a data collection instrument, based on empirically validated instrumentation, clients from several homeless service providers in the City of San Bernardino were assessed for the level of self-determination and autonomy support they experience within these agencies. Outcome measures included such things as whether the client was going to school, had a job and had a bank account. Overall, the results of the study were inconclusive, though some interesting post hoc observations were made. It was the primary aim of this paper to increase the knowledge base of the local network of homeless service providers and to promote the compassionate, equitable, and dignified treatment of the population they serve.
125

Introduction to Probability Theory

Chen, Yong-Yuan 25 May 2010 (has links)
In this paper, we first present the basic principles of set theory and combinatorial analysis which are the most useful tools in computing probabilities. Then, we show some important properties derived from axioms of probability. Conditional probabilities come into play not only when some partial information is available, but also as a tool to compute probabilities more easily, even when partial information is unavailable. Then, the concept of random variable and its some related properties are introduced. For univariate random variables, we introduce the basic properties of some common discrete and continuous distributions. The important properties of jointly distributed random variables are also considered. Some inequalities, the law of large numbers and the central limit theorem are discussed. Finally, we introduce additional topics the Poisson process.
126

Assessment of cerebral venous return by a novel plethysmography method

Zamboni, P., Menegatti, E., Conforti, P., Shepherd, Simon J., Tessari, M., Beggs, Clive B. January 2012 (has links)
BACKGROUND: Magnetic resonance imaging and echo color Doppler (ECD) scan techniques do not accurately assess the cerebral venous return. This generated considerable scientific controversy linked with the diagnosis of a vascular syndrome known as chronic cerebrospinal venous insufficiency (CCSVI) characterized by restricted venous outflow from the brain. The purpose of this study was to assess the cerebral venous return in relation to the change in position by means of a novel cervical plethysmography method. METHODS: This was a single-center, cross-sectional, blinded case-control study conducted at the Vascular Diseases Center, University of Ferrara, Italy. The study involved 40 healthy controls (HCs; 18 women and 22 men) with a mean age of 41.5 +/- 14.4 years, and 44 patients with multiple sclerosis (MS; 25 women and 19 men) with a mean age of 41.0 +/- 12.1 years. All participants were previously scanned using ECD sonography, and further subset in HC (CCSVI negative at ECD) and CCSVI groups. Subjects blindly underwent cervical plethysmography, tipping them from the upright (90 degrees ) to supine position (0 degrees ) in a chair. Once the blood volume stabilized, they were returned to the upright position, allowing blood to drain from the neck. We measured venous volume (VV), filling time (FT), filling gradient (FG) required to achieve 90% of VV, residual volume (RV), emptying time (ET), and emptying gradient (EG) required to achieve 90% of emptying volume (EV) where EV = VV - RV, also analyzing the considered parameters by receiver operating characteristic (ROC) curves and principal component mathematical analysis. RESULTS: The rate at which venous blood discharged in the vertical position (EG) was significantly faster in the controls (2.73 mL/second +/- 1.63) compared with the patients with CCSVI (1.73 mL/second +/- 0.94; P = .001). In addition, respectively, in controls and in patients with CCSVI, the following parameters were highly significantly different: FT 5.81 +/- 1.99 seconds vs 4.45 +/- 2.16 seconds (P = .003); FG 0.92 +/- 0.45 mL/second vs 1.50 +/- 0.85 mL/second (P < .001); RV 0.54 +/- 1.31 mL vs 1.37 +/- 1.34 mL (P = .005); ET 1.84 +/- 0.54 seconds vs 2.66 +/- 0.95 seconds (P < .001). Mathematical analysis demonstrated a higher variability of the dynamic process of cerebral venous return in CCSVI. Finally, ROC analysis demonstrated a good sensitivity of the proposed test with a percent concordant 83.8, discordant 16.0, tied 0.2 (C = 0.839). CONCLUSIONS: Cerebral venous return characteristics of the patients with CCSVI were markedly different from those of the controls. In addition, our results suggest that cervical plethysmography has great potential as an inexpensive screening device and as a postoperative monitoring tool.
127

Sur les familles des lois de fonction de hasard unimodale : applications en fiabilité et analyse de survie

Saaidia, Noureddine 24 June 2013 (has links)
En fiabilité et en analyse de survie, les distributions qui ont une fonction de hasard unimodale ne sont pas nombreuses, qu'on peut citer: Gaussienne inverse ,log-normale, log-logistique, de Birnbaum-Saunders, de Weibull exponentielle et de Weibullgénéralisée. Dans cette thèse, nous développons les tests modifiés du Chi-deux pour ces distributions tout en comparant la distribution Gaussienne inverse avec les autres. Ensuite nousconstruisons le modèle AFT basé sur la distribution Gaussienne inverse et les systèmes redondants basés sur les distributions de fonction de hasard unimodale. / In reliability and survival analysis, distributions that have a unimodalor $\cap-$shape hazard rate function are not too many, they include: the inverse Gaussian,log-normal, log-logistic, Birnbaum-Saunders, exponential Weibull and power generalized Weibulldistributions. In this thesis, we develop the modified Chi-squared tests for these distributions,and we give a comparative study between the inverse Gaussian distribution and the otherdistributions, then we realize simulations. We also construct the AFT model based on the inverseGaussian distribution and redundant systems based on distributions having a unimodal hazard ratefunction.
128

Změna třídního klimatu po odchodu žáků na osmiletá gymnázia / The Change of Classroom Climate in Czech Elementary Schools with the Departure of Students into High-Track Schools

Holubová, Markéta January 2018 (has links)
The aim of the dissertation is to compare the psychosocial climate of the classes between the 5th and 6th grades of Czech elementary school. In the train of pupils' leaving into the high- tracked schools there are significant organizational changes in the classes of the 6th grade. This theme includes the phenomenon of the early tracking, when some pupils can leave the mainstream of education (elementary school) and start attending the high-tracked schools (multi-year gymnasium). The aim of our study is to contribute to the research, that with the departure of students into high-tracked schools the psychosocial climate in the classes of the 6th grade unequivocally exacerbates. We are also interested in which specific students are accepted into high-tracked schools, and whether they are effective classroom leaders and socio- metric stars. In our study, we also find out the classroom positions of students who are continuously educated in the 5th and 6th grades of the elementary schools and their classmates, who have come as new students into the classes of the 6th grade. In the theoretical section we introduce the foreign and domestic researches which were conducted on the association between tracking and classroom climate. The empirical part inquiries into a detailed analysis of quantitative research...

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