Research Project (M.B.A.) - Simon Fraser University, 2005. / Research Project (Faculty of Business Administration) / Simon Fraser University. MBA-MOT Program. Senior Supervisor : Dr. Aidan Vining.

Research Project (M.B.A.) - Simon Fraser University, 2005. / Research Project (Faculty of Business Administration) / Simon Fraser University. MBA-MOT Program. Senior Supervisor : Dr. Aidan Vining.

published_or_final_version / abstract / Community Medicine / Doctoral / Doctor of Philosophy

The dissertation examines how changes in the race, gender and age composition of poverty over the past twenty years are linked to the unique experiences of particular birth cohorts. Demographer Richard Easterlin argues that generations born between 1944 and 1963 (the 'baby boom') face exceptional labor market competition and economic vulnerability due to their large numbers. Extending this theory, the central question of the dissertation is: Have families headed by the baby boom generation been more likely to be poor in the 1970s and 1980s compared to families headed by generations born prior to the baby boom? The findings indicate that among whites, the answer is clearly 'yes.' For African Americans, the answer appears to be 'no.' Results consistently show that the risk of poverty has been increasing with each successive generation of white family born since 1944. On the other hand, there is no evidence that black families headed by an individual born during the baby boom are more likely to be poor than those headed by previous generations. For both races, however, the most striking finding concerns the generation which was born after the baby boom. White and black families headed by adults born since 1964 are more likely to be poor compared to families headed by the older generations. The cohort effects on poverty are net of family structure, age of the family head, and period. The effects also persist controlling for employment variables which reflect labor market competition. Hypotheses about demographic trends in poverty from 1967 to 1987 are tested using multivariate analyses of a cross-sectional dataset (the Current Population Survey) and a longitudinal dataset (the Panel Study of Income Dynamics). Log-linear analyses of the Current Population Survey decompose the effects of family structure, age, period and cohort on poverty for all families as well as families headed by women. Discrete-time event history analyses of the PSID are used to model poverty among all families in any given year between 1969 and 1987. The dynamics of poverty are further examined in comparisons of nested multinomial logistic regression models of poverty entrances and exits among wives and female-headed families.

Suicide is one of the major health issues and causes of mortality in modern societies. A global morality rate of suicide is 16 persons per 100,000 according to the World Health Organization report. Fortunately, the rates in most OECD countries have shown a dramatic decrease over the last 20 years. There are, however, two important exceptions, Japan and South Korea. The suicide rates in these two countries have been on an increasing trend. Because the two neighboring countries share similar socio-demographic contexts, I investigated the effects of the three time-related demographic variables (age, period, and cohort) on suicide rates in Japan and South Korea. The Age-Period-Cohort Intrinsic Estimator model was operated using data of vital statistics and population census from the Statistics Bureau and the Ministry of Internal Affairs and Communications in Japan, and cause of death data and population census from Statistics Korea in South Korea. Even though the two countries are neighboring countries that have had some similar socio-demographic contexts, the factors contributing to increasing suicide rates vary in each country. The result showed age effects in Japan greatly contributed to suicide compared to period and cohort effects, and the age effects were highest during the fifties age bracket. On the other hand, South Korea turned out to have more compound reasons, showing pronounced age effects in the elderly population, increasing period effects, and the strong cohort effects of the current elderly and middle-aged populations. From this result, although Japan and South Korea are neighboring countries with shared histories, industrial structures, social systems, and some similar demographic characteristics, the cause of increasing suicide rates in the two countries clearly varies and the efforts for preventing suicide must also vary depending on the social contexts of each country.

This thesis examines the life-cycle profile of informal employment in Turkey. To achieve this goal cohort analysis technique and 2000-2007 Household Labor Force Survey micro level data of State Institute of Statistics is used. Informal sector is composed of people working without social security coverage due to their current jobs. Analyzes are conducted both for the total sample and six education groups separately. Besides informal employment, labor force participation and unemployment rates are also examined and using these variables net transitions between the sectors over the life-cycle are tired to be observed. According to the results / informal employment rate decreases at young ages, relatively stable at middle ages and then increases rapidly at older ages. Moreover, strong cohort effects are found in many variables and the cross section profiles differ from the true life-cycle profiles remarkably.

Over the past several decades, the senior age group has become the fastest growing segment of the population in the United States (Warner, 2011). This study seeks to contribute to the ongoing discussion of the impacts that the increases in senior travel will have on the future transportation systems and planning efforts. The main objective of this research is to conduct an explorative analysis of the changes in senior travel behavior over the past two decades and discuss the implications of these changes to transportation planning in the future. This thesis seeks to further understanding of this topic by providing a detailed analysis and consideration of relevant contexts through a review of previous studies and the author's background in the field of transportation. Results indicate significant changes in travel behaviors and make-up of the senior population. Over the three (1990, 2001, and 2009) survey periods, senior travel changed as a result of increased activity and a need to maintain their typical way of life well into older age. As the baby boom generation continues to out travel each previous generation, there is no evidence to assume that as they reach retirement age that trend will end. Seniors today are remaining active and working well into their older age and the age group has continued to increasingly contribute to total travel. These increases will be echoed by the baby boom generation and must be considered by traffic forecasters, researcher and policy makers in the future.

This study focuses on the nature of the school advisor's roles within a collaborative educational setting, specifically, a partnership involving a school district, university and teachers association referred to as the Richmond Teacher Education Project. The study investigates how school advisors view their roles and responsibilities within a cohort group. School advisors describe their experiences according to role, motivations, preparation and training, improvements to the program and professional/ethical considerations. Findings from the study indicate that the role development of school advisors is dependent on the amount of time spent as a member of the Richmond Practicum Project and on the relationship-building process between the student teachers and other members of the cohort grouping. All subjects mention some difficulty in their role as the primary evaluator and believed that the faculty advisor should share this role.

Estimation of current levels of human immunodeficiency virus (HIV) incidence is essential for monitoring the impact of an epidemic, determining public health priorities, assessing the impact of interventions and for planning purposes. However, there is often insufficient data on incidence as compared to prevalence. A direct approach is to estimate incidence from longitudinal cohort studies. Although this approach can provide direct and unbiased measure of incidence for settings where the study is conducted, it is often too expensive and time consuming. An alternative approach is to estimate incidence from cross sectional survey using biomarkers that distinguish between recent and non-recent/longstanding infections. The original biomarker based approach proposes the detection of HIV-1 p24 antigen in the pre-seroconversion period to identify persons with acute infection for estimating HIV incidence. However, this approach requires large sample sizes in order to obtain reliable estimates of HIV incidence because the duration of antigenemia before antibody detection is short, about 22.5 days. Subsequently, another method that involves dual antibody testing system was developed. In stage one, a sensitive test is used to diagnose HIV infection and a less sensitive test such is used in the second stage to distinguish between long standing infections and recent infections among those who tested positive for HIV in stage one. The question is: how do we combine this data with other relevant information, such as the period an individual takes from being undetectable by a less sensitive test to being detectable, to estimate incidence? The main objective of this thesis is therefore to develop likelihood based method that can be used to estimate HIV incidence when data is derived from cross sectional surveys and the disease classification is achieved by combining two biomarker or assay tests. The thesis builds on the dual antibody testing approach and extends the statistical framework that uses the multinomial distribution to derive the maximum likelihood estimators of HIV incidence for different settings. In order to improve incidence estimation, we develop a model for estimating HIV incidence that incorporate information on the previous or past prevalence and derive maximum likelihood estimators of incidence assuming incidence density is constant over a specified period. Later, we extend the method to settings where a proportion of subjects remain non-reactive to a less sensitive test long after seroconversion. Diagnostic tests used to determine recent infections are prone to errors. To address this problem, we considered a method that simultaneously makes adjustment for sensitivity and specificity. In addition, we also showed that sensitivity is similar to the proportion of subjects who eventually transit the “recent infection” state. We also relax the assumption of constant incidence density by proposing linear incidence density to accommodate settings where incidence might be declining or increasing. We extend the standard adjusted model for estimating incidence to settings where some subjects who tested positive for HIV antibodies were not tested by a less sensitive test resulting in missing outcome data. Models for the risk factors (covariates) of HIV incidence are considered in the last but one chapter. We used data from Botswana AIDS Impact (BAIS) III of 2008 to illustrate the proposed methods. The general conclusion and recommendations for future work are provided in the final chapter. / Theses (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2013.

Older adults have the lowest mental health utilization of any age cohort. This study compared baby boomers, born between 1946 and 1964 versus older adults born in 1944 or earlier, on attitudes and intentions to utilize mental health services. Ajzen’s theory of planned behavior and its related constructs of attitudes, subjective norm, perceived behavioral control, and intentions were used as a theoretical model. The Inventory of Attitudes toward Seeking Mental Health Services (IASMHS) and Beliefs About Psychological Services (BAPS) were used for measuring the constructs in the theory of planned behavior. Gender and previous mental health service utilization were also measured. Participants (n = 401) included current and retired faculty and staff from a mid-sized Midwestern University. Statistical analysis, using MANOVA, found main effects for previous mental health experience and age cohort, but not for gender. Those with previous mental health service experience expressed more positive attitudes, intentions, and perceived behavioral control over receiving mental health services. Contrary to the primary hypothesis, the older adult cohort expressed more positive attitudes, greater intentions, was less affected by the subjective norm, and had more perceived behavioral control than baby boomers. Regression analyses, using gender, previous mental health service use, attitudes, subjective norm, and perceived behavioral control accounted for 55.7% of the variance in intentions for the older adult cohort and 58.2% for baby boomers. For both cohorts, attitudes accounted for the greatest amount of variance. Promoting positive attitudes through reducing environmental and economic barriers and increasing education regarding mental health services is likely to increase mental health service utilization in baby boomers and older adults. / Department of Counseling Psychology and Guidance Services