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Socio-Economic Status and Community Integration: A Study of Formal and Informal Participation of Urban Migrants
No full textThe focus of this thesis is twofold, the first being theoretical, the second being methodological. Chapter I consists of a review of the migration literature, specifically that relevant to tie relationship between socio-economic status and the migrant's integration into a new community. From this review, a number of hypotheses are generated and subsequently tested employing data from the Migrant Relocation Study. Socio-economic status is postulated to be related to both formal social participation in voluntary associations and informal social participation--both important aspects of integration. The methodological portion of the thesis consists of the use of a number of methodological techniques, including specifically, index construction, a two wave path analysis and a correction for measurement error, as aids in testing the hypotheses. Factor analysis, one method of index construction is applied to the informal social participation indicators and points out that categories of social relationships are somewhat more complex than a simple kin, non-kin dichotomy which was used previously in the literature. Instead of grouping all kin together, kin can be more accurately represented by considering it to be at least three separate variables and regarding non-kin, there is reason to distinguish between friends, neighbours and co-workers. The hypotheses generated by tho review of the literature are tested using the technique of causal modelling. The particular two wave path model used to test the hypotheses is suggested by Heise (1969). It is for application to survey-type data with measurements made on the same variables and the sample at two times. The lagged paths representing the impact of one variable on another during the period between measurements are the basis for causal inference. This model, thus, allows a test of a causal relationship between socio-economic status and social participation. An important contribution in this thesis is the consideration of measurement error. This thesis attempts to take measurement error into account in solving the path model. Reliability coefficients are calculated for each indicator in the path analysis and the correlation coefficients generated from these are subsequently corrected for attenuation. These corrected coefficients are then used to test the two wave path model. The results of this thesis are not specifically conclusive. Employing the corrected model support is found for a number of the hypotheses. Results generated from the uncorrected model, however, are somewhat more problematic. Support is found for a causal effect of socio-economic status on formal social participation in voluntary associations and a weak effect in a negative direction of socio-economic status on informal social participation with kin. The analysis also suggests that the causal effect of socio-economic status on informal social participation with friends is in a positive direction and with neighbours is in a negative direction.Master of Arts (MA
Intimidation Culture: Free Expression in the Age of Social Media
No full textWhile social media platforms have dramatically bolstered the ability of ordinary people to broadcast their views to large audiences, the dynamics of online communication have also had a stifling effect on public discourse. Due to social media's tendency to reward content that is extreme and divisive, it is often the case that people with more moderate views engage in self- censorship and preference falsification in order to evade online backlash. This project deploys the philosophy of the seminal liberal thinker John Stuart Mill in order to examine the phenomenon of online intimidation culture and assess its pernicious impact on society. Three social goods are identified that are jeopardized when thought and expression become constrained due to formal or informal censorship. These are critical intellectual faculties, authenticity in discourse, and equity in accountability. It is argued that those who are interested in preserving these social goods have strong grounds for resisting the pressures of intimidation culture and working to establish an atmosphere of free expression wherein people from diverse backgrounds can explore and assess a broad array of competing ideas without fear of punishment. It is likewise argued that despite the persistent toxicity of social media discourse, the societal harms that it produces can be mitigated through the cultivation of institutions that are resilient in the face of pressure campaigns, and firmly committed to intellectual diversity and freedom of expression. Finally, it is posited that social media is not inherently at odds with a Millian atmosphere of free expression. If the incentives that animate online discourse are realigned in order to encourage reasoned discourse rather than performative antagonism, then this technology could be an asset to humans' capacity for compassion by facilitating greater communication and understanding between individuals and groups from different parts of the world.DissertationDoctor of Philosophy (PhD)While social media platforms have dramatically bolstered the ability of ordinary people to broadcast their views to large audiences, the dynamics of online communication have also had a stifling effect on public discourse. Due to social media's tendency to reward content that is extreme and divisive, it is often the case that people with more moderate views engage in self- censorship and preference falsification in order to evade online backlash. This project deploys the philosophy of the seminal liberal thinker John Stuart Mill in order to examine the phenomenon of online intimidation culture and assess its pernicious impact on society. It is argued that despite the persistent toxicity of social media discourse, the societal harms that it produces can be mitigated through the cultivation of institutions that are resilient in the face of pressure campaigns, and firmly committed to intellectual diversity and freedom of expression
Stochastic EM Algorithm-based Likelihood Inference for Spatial Cure Rate Models Based on Some Flexible Distributions
No full textWith geographic information systems (GIS) widely accessible, modeling spatially referenced data has become increasingly relevant. Spatial survival analysis addresses spatial dependence by analyzing location-linked time-to-event data. In this work, we adopt a competing risks framework, assuming that the number of causes leading to an event follows a discrete power series (PS) distribution. The PS cure rate model is highly flexible and can recover many standard cure models through specific choices of its power parameter and series function. We focus on three activation schemes: first, random, and last activation. Spatial effects are modeled via a Gaussian process (Gaussian random field) and incorporated into the cure rate models as spatial frailties, capturing the influence of geographic location on survival times for susceptible individuals and cure rate. We propose a flexible baseline hazard function based on the generalized extreme value (GEV) distribution, which unifies several continuous distributions. By adjusting scale and shape parameters, the GEV includes the Gumbel (Type I), Fréchet (Type II), and Weibull (Type III) distributions as special cases. Parameter estimation is performed using a Stochastic EM (SEM) algorithm, which avoids computing conditional expectations, is free from saddle point problems, insensitive to starting values, and performs well with small to moderate clinical sample sizes. Extensive simulations demonstrate robust convergence and strong model discrimination via information-based criteria.
We apply the proposed models to a smoking cessation dataset, visualizing spatial effects on hazard using maps. Cure rates and survival probabilities are compared with and without spatial effects, and the necessity of including spatial frailties is confirmed through a likelihood ratio test. The results highlight the importance of accounting for geographic variation in survival analysis and demonstrate the flexibility and applicability of the proposed spatial PS cure rate framework.ThesisCandidate in Philosoph
Not all pathways lead to success: How temporary permit type shapes immigrant earnings in Canada
No full textThis study challenges the assumption that all two-step immigration pathways lead to better labour market integration by showing that outcomes vary significantly by temporary permit type. Using Statistics Canada’s Longitudinal Immigration Database (IMDB), it compares earnings trajectories of four International Mobility Program subgroups with one-step immigrants. Post-graduate work permit holders and intra-company transferees earn more initially, while working holidaymakers earn less and spouses’ outcomes vary by gender. The findings fill a key gap by highlighting permit-specific disparities and can inform government decisions on temporary program design, selection criteria, and forecasts of immigrant economic integration
EXPLORING THE ROLE OF EXTERNAL MEMBERS IN COMPETENCE COMMITTEES: A QUALITATIVE CASE STUDY OF RESIDENCY PROGRAMS AT MCMASTER UNIVERSITY
No full textIntroduction: Competency-based medical education (CBME) is transforming residency training by emphasizing outcomes, including the knowledge, skills, and professional behaviours required for high quality patient care. In Canada, the Royal College of Physicians and Surgeons of Canada (RCPSC) has implemented Competence by Design (CBD) as its national CBME framework. Within CBD, competence committees (CCs) play a critical role in reviewing residents’ progress and making decisions about their advancement. An increasing number of residency programs have begun to include external members in their CC meetings, such as faculty from other departments, researchers, or non-physician healthcare providers (e.g., nurses or social workers). However, scholarly attention to how program CC members and residents perceive external members and the challenges external CC members encounter has been limited.
Methods: This qualitative case study was conducted at McMaster University across multiple residency programs. Data were collected through semi-structured interviews with program CC members, external members, and residents, as well as direct observations of CC meetings. All interviews were transcribed, and data were analyzed inductively using Yin’s “working your data from the ground up” strategy. Transcripts were coded and organized; themes were iteratively developed, reviewed, and refined.
Results: Five themes were developed: 1) Multiple models and roles of external CC members, 2) Preference for one type of external CC member’s expertise over another, 3) External CC members as promoters of integrity, 4) Facilitators for the inclusion of
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external CC members in CCs, and 5) Practical challenges and structural constraints in the inclusion process of external members in CCs.
Conclusion: The findings of this work confirm that external CC members are perceived to be a positive addition to CCs, enhancing decision-making processes. The findings have also identified multiple facilitators and challenges to the inclusion of external members in CCs
MOLECULAR CATALYSIS FOR ELECTROCHEMICAL NITRATE CONVERSION TO AMMONIA
No full textElectrochemical reduction of nitrate (NO3⁻) to ammonia (NH3) offers a pathway to decentralized nitrogen cycle remediation and sustainable NH3 synthesis. This thesis advances the application of molecular catalysts in electrochemical NO3⁻ reduction to NH3 by elucidating how active site coordination and the local atomic environment govern activity, selectivity, and stability. Across three manuscripts, (i) the impact of second shell coordination on metal-N4 macrocycles beyond first-shell electronics was established (ii) the active phase identity and degradation pathways of Fe- and Cu-based phthalocyanine/porphyrin catalysts under cathodic potentials were resolved, (iii) Design challenges of dual site molecular catalysts were identified using CuPc and FePc, and (IV) the impact of electronic properties and catalyst wettability on the performance of molecular catalysts in NO3- reduction using a series of functionalized FePc-R/CNTs was decoupled. Methodologically, in situ X-ray absorption spectroscopy was integrated with post-mortem microscopy/diffraction, density-functional theory, and coupled mass-transport/reaction modeling, and electrochemical evaluation was performed to identify performance descriptors in molecular catalysts. New discoveries include: (1) metal identity and second shell (porphyrin vs phthalocyanine) in molecular catalysts impacts the stability and activity (2) revealing peripheral substituents affect electronic properties and wettability and that electronic trends are frequently masked, or amplified, by local hydrophobicity, (3) a tandem Fe-Cu design paradigm, translated from molecular insights, that identify key challenges in dual site catalysts designs and key factors playing a role in obtaining synergy between the active sites.
The major emphasis of the thesis is that coordination chemistry and local environment co-determine selectivity in an eight-electron nitrate reduction reaction, and that operando-validated molecular models can provide transferable rules for scalable architectures. The contributions to knowledge are actionable: design principles linking Hammett-type substituent metrics and wettability to NO3- reduction kinetics; operando criteria to validate active-phase identity; and a blueprint for dual site catalysis that bridges molecular precision with device-relevant performance
Speaking for the Nation: Representation through Indigenous and Minority Language Recognition in Taiwan, New Zealand and Southeast Asia
No full textThis “sandwich” dissertation argues that Indigenous and minority language recognition offers a novel way to examine how political representation unfolds in practice. I trace how group claims are articulated and institutionalized by diverse actors working within multiple settings, and how the outcomes of representational work shape perceptions of inclusion and legitimacy. The first chapter finds that Taiwan’s Council of Indigenous Peoples drives Indigenous language policy, demonstrating how representation occurs through executive rather than legislative institutions. The second chapter finds that Māori leaders and policy actors in New Zealand advanced and articulated Māori language priorities across multiple institutions. The third chapter analyzes survey data from Southeast Asia and finds that official language recognition is associated with higher perceptions of democracy and feelings of national pride among minority speakers. Together, the chapters demonstrate that language recognition is negotiated across multiple actors and sites, and can enhance legitimacy and belonging for minority communities
Precarious employment is linked to workplace injuries in Ontario, Canada
No full textPrecarious employment, referring to work that is unstable and insecure, has important implications for workplace health and safety. Workers in precarious employment often face overlapping risks, including inadequate training, high job turnover, fear of reprisal for reporting unsafe conditions, and gaps in regulatory protections. Economic insecurity may also require them to work longer hours, take on multiple jobs, or accept dangerous work. For all these reasons, precarious employment is hypothesized to increase the likelihood of experiencing an injury on the job. This study tested that hypothesis by examining the association between precarious employment and workplace injuries in Ontario, Canada
RISK ASSESSMENT OF CANCER AND OCULAR DISEASES FOLLOWING LOW-DOSE COMPUTED TOMOGRAPHY EXPOSURE IN ONTARIO, CANADA
No full textComputed tomography (CT) is an essential tool in modern medicine, enabling quick and accurate diagnosis of various conditions. Since CT relies on ionizing radiation (IR) to produce internal images, its widespread use has led to concerns regarding patient safety, particularly in children who are more sensitive. In this thesis, the potential association between low-dose IR exposure from CT scans and the development of certain ocular conditions and cancers among residents of Ontario, Canada was studied.
Data on CT scans were obtained from the Ontario Health Insurance Plan (OHIP) database. We first estimated organ doses from various CT procedures based on sex, age, and scan year, using CT dose index (CTDI) values from national surveys and dose coefficients from the National Cancer Institute dosimetry system for CT (NCICT). These dose estimates were then used to assess disease risk. All analyses were conducted using multivariate Cox regression, including demographic factors and relevant predisposing medical conditions as covariates. Appropriate lag periods were applied to account for disease latency.
Using OHIP data from 1994 to 2023, we evaluated the risk of cataract and glaucoma in relation to radiation dose to the eye lens following head CT scans. Analyses based on cataract surgery, glaucoma diagnosis, or glaucoma treatment, lagged by 3, 5, and 7 years, showed no increased risk due to radiation exposure. Similarly, using data from 1992 to 2019, we studied the risk of leukemia, lymphoma, and brain tumors in individuals who had received CT scans at or before age 19. Analyses lagged by 2, 5, and 10 years revealed some elevated risks for the primary cancer types but also highlighted no association or even reduced risk for some known radiogenic cancer sub-types. Taken together, the results did not support a clear association between cancer risk and CT exposure in this population. Overall, this thesis provides valuable insight into the potential risks associated with CT scans, supporting clinicians in making more informed decisions when ordering these procedures
Travels in Africa and the Middle East
No full textHistorical travelogue in Africa and the Middle EastHistorical travelogue in South Africa, Algeria, Morocco, United Arab Emirates, Israel and Turkey