No description available.

The primary aim of this thesis is the elucidation of covariate effects on the dependence structure of random variables in bivariate or multivariate models. We develop a unified approach via a conditional copula model in which the copula is parametric and its parameter varies as the covariate. We propose a nonparametric procedure based on local likelihood to estimate the functional relationship between the copula parameter and the covariate, derive the asymptotic properties of the proposed estimator and outline the construction of pointwise confidence intervals. We also contribute a novel conditional copula selection method based on cross-validated prediction errors and a generalized likelihood ratio-type test to determine if the copula parameter varies significantly. We derive the asymptotic null distribution of the formal test. Using subsets of the Matched Multiple Birth and Framingham Heart Study datasets, we demonstrate the performance of these procedures via analyses of gestational age-specific twin birth weights and the impact of change in body mass index on the dependence between two consequent pulse pressures taken from the same subject.

Utilising a historical perspective and drawing upon path dependence theory, the thesis focuses on the question of a political union of Canada’s three Maritime provinces - Nova Scotia, New Brunswick and Prince Edward Island - between 1960 and 1980. Drawing on archival sources and interviews the thesis examines the factors which increased the potential for a union and resulted in a political union not occurring in this period. The thesis reveals how the intensification of Quebec separatism throughout the 1960s and 1970s threatened to separate the region geographically from the rest of the country. It also shows that the regional expansionist agenda of the federal government undermined provincial jurisdiction as it sought to eliminate economic underdevelopment in the Maritime region. These factors coupled with the dynamics of province-building and the political ambition of key political leaders in the Maritimes created the impetus for a political union in the 1960s. The thesis pays particular attention to the Maritime Union Study (MUS), established in 1968 by the Maritime premiers to investigate the union question. The thesis argues that the MUS was a critical juncture because it presented the premiers with a number of alternative choices for political change, including its main recommendation: the establishment of a political union. However, the thesis reveals that upon the publication of the final report of the MUS in November 1970, the ramifications of the 1970 October Crisis in Quebec and the recent election of new premiers in Nova Scotia and New Brunswick reconfigured the national and regional contexts in which a political union was considered. This reconfiguration led to a new form of institutionalised intergovernmental relations called the Council of Maritime Premiers (CMP). The CMP was a confederal structure which respected the provincially-focused decision-making capacity of the Maritime premiers. The key conclusion of the thesis is that engagement with the question of a political union reflected a balance between political environment and political agency. The national political environment encouraged the consideration of a political union because it revealed a vulnerability to external occurrences which were beyond the control of the three provinces and connected with an internal logic for change. A political union was seen as a way for the region to develop the capacity to become economically self-sufficient and in turn neutralise the implications of unexpected externalities. However, alternative opportunities for political action were pursued when the national political environment became reconfigured and new political leaders were elected. This dynamic explains why, despite a critical juncture, a union did not happen. As such, the thesis shows that the current understanding of change to path dependent settings is confirmed. Established trajectories will be more inclined towards persistence than change. The key contribution of the thesis to path dependence theory is that change is not the default outcome of a critical juncture. If change is viable, considered but not ultimately selected it is no less a critical juncture than those which produce enduring change. On a broader level, the thesis gives an indication as to the difficulty of political amalgamations between constitutionally protected entities within established federal states.

This paper analyses the process of wealth accumulation with regard to the path dependence theory. Based on the theoretical foundations of Robert King Merton, Vilfredo Pareto and Pierre Bourdieu, mechanisms of wealth accumulation are analyzed. These mechanisms, which are understood as direct and indirect network effects, are formalized using the statistical computing software R. A base model without any mechanisms of wealth accumulation is developed, which makes it possible to include the analyzed mechanisms step by step and observe their effects on the process of wealth accumulation and social inequality. Piketty's findings from his work Capital in the 21st Century are included in the formalized models of wealth accumulation, in particular the relationship between the rate of return on capital and the growth rate of the economy. (author's abstract)

Measurements of line width parameters for eleven rotational transitions of type (J -- J + 1) of SO2 were made and are reported herein. The line width quantum number (J) trend was obtained. The microwave spectrograph used for these measurements of line width is described. Operational methods to operate the spectrograph are presented and discussed, with particular attention given to how to measure the line width. Suggestions for future avenues of probing this molecule to ascertain the non-uniform behavior of the line width parameter over the quantum number and frequency range are given.

Resonators are one of the most important parts of electronic products. They provide a stable reference frequency to ensure the operation of these products. Recently, the electronic products have the trend of miniaturization, which rendered the size reduction of the resonators as well [1]. Better design of the resonators relies on a better understanding of the crystals' nonlinear behavior [2]. The nonlinearities affect the quality factor and acoustic behavior of MEMS (Micro-Electro-Mechanical-System) and nano-structured resonators and filters [3]. Among these nonlinear effects, Drivel Level Dependence (DLD), which describes the instability of the resonator frequency due to voltage level and/or power density, is an urgent problem for miniaturized resonators [2]. Langasite and GaPO4 are new promising piezoelectric material. Resonators made from these new materials have superior performance such as good frequency-temperature characteristics, and low acoustic loss [2]. In this thesis, experimental measurements of drive level dependence of langasite resonators with different configurations (plano-plano, single bevel, and double bevel) are reported. The drive level dependence of GaPO4 resonators are reported as well for the purpose of comparison. The results show that the resonator configuration affects the DLD of the langasite resonator. Experiments for DLD at elevated temperature are also performed, and it was found that the temperature also affects the DLD of the langasite resonator.

Research suggests that substance use is a risk factor for increased suicidal ideation. This study explored the relationship between substance use, suicidal ideation, and impulsivity in a sample of college students and individuals seeking outpatient treatment. Participants were interviewed for information on severity of suicidal ideation and substance use. Participants completed the Psychiatric Diagnostic Screening Questionnaire, the substance use section of the Structured Clinical Interview for the DSM-IV, the Alcohol Use Disorders Identification Test, the Scale for Suicide Ideation, and the UPPS-P Impulsivity Behavior Scale. These measures were used to determine the amount of variance in suicidal ideation accounted for by substance use. Variables reflecting substance use classification, frequency, and severity were used to predict severity of suicidal ideation.

Dependency is defined as authentic or pathological and is seen as a component important to the treatment of patients with chronic illness. It is hypothesized that a significant portion of ecology patients will meet the criteria for pathological dependence and differ on psychological and physiological parameters from those who do not. This study strongly supports the first two hypotheses but does not find that the two groups differ physiologically. One hundred eleven variables are surveyed. Fifty-two show significant differences between the groups and 29 are significant at greater than the .0001 level. A discriminant analysis was used to determine the least number of orthogonal variables that best discriminate between the groups. These are MMPI Scales 8, 3, subscale Ma2, employment status, and early childhood illness.

A growing body of research is examining effective treatment(s) for individuals with comorbid posttraumatic stress disorder (PTSD) and alcohol dependence (AD). However, treatments for this comorbid population have been inadequately studied in the longer term. This study represents a long-term follow-up assessment of a randomized controlled trial that compared combined therapy (prolonged exposure + naltrexone) with monotherapies (prolonged exposure or naltrexone) for patients with PTSD and AD (see Foa, Yusko, McLean et al., 2013). Attempts were made to contact 120 participants 5-10 years after the original trial to assess the maintenance of treatment gains. Nineteen individuals were located and agreed to participate. A series of mixed ANCOVAs were conducted with PTSD symptom severity and percentage of days drinking and heavy drinking as the dependent variables. Findings revealed that reductions in PTSD symptoms and drinking behaviors generally were maintained 5-10 years after treatment. There was some relapse in heavy drinking days, and combination treatment was most effective for long-term PTSD outcomes. Challenges of conducting follow-up research with this population, implications and limitations of the present findings, and directions for future research are discussed.

The purpose of this study was to examine the relationship between history of parental substance abuse and substance use and psychiatric severity measures in a sample of treatment-seeking, pregnant women who meet DSM-IIIR criteria for lifetime opioid and cocaine abuse and/or dependence (N=260). The study examined whether a dose-response relationship was observed between number of parents affected by substance use problems (0, 1, and 2) and degree of women’s substance use and psychiatric severity. Results did not support a dose-response relationship between density of parental problems and substance use and psychiatric severity. However, some differences in severity were seen at different levels and types of parental density. Overall, the present study supports the need to further examine parental history of substance abuse as a potential risk factor for more severe substance use and psychiatric problems. Study findings have important implications for the screening and treatment of substance dependence during pregnancy.