VictorJuiz/thesis huggingface dataset:
Three Essays on Total Returns to the Employment Relationship
Keywords: compensation
employment relationship

This dissertation examines the total returns to the employment relationship from a variety of perspectives. In the first chapter, I examine different forms of training and study its influence on individual turnover. My second chapter examines the impact of mandatory volunteer/work experience in high school on the employment and wage decisions of youths. In my final chapter, I examine flexible work hours as a moderator in the relationship between workplace strategy and organizational performance. The first chapter highlights the importance of the type of training provided to the employee in order to avoid voluntary turnover. I compare the impact of institutional training compared to course training on voluntary turnover. Estimates indicate that employees who receive course training are more likely to leave the firm for another job, while employees who receive institutional training are more likely to stay with the firm. The results indicate that different types of training have differential impacts on the employee’s turnover decision. The second chapter utilizes a provincial policy reform that requires either working at a paid job or volunteering as a mandatory high school graduation requirement and examines its impact on employment outcomes. I propose that this reform causes a change in the perceptions of work by individuals which may lead them to sacrifice income for an altruistic purpose. In addition, the low quality of jobs found working or volunteering in high school may result in a distaste for work and hence provide motivation for enrolling in post-secondary education. The empirical results support this argument as the reform resulted in an increased likelihood of high school graduates to pursue post-secondary education, while those who entered the labour force had a lower probability of employment and lower wages. The final chapter examines the generalizeable conditions under which flexible work schedules are beneficial to firm performance. I find that flextime is not a best practice that is applicable across all firm environments. Instead, flextime only increases profitability when implemented within a workforce strategy focused on employees. Conversely, flextime when implemented with a cost-reduction strategy has detrimental effects on firm profits.
Estimating Non-homogeneous Intensity Matrices in Continuous Time Multi-state Markov Models
Keywords: Biostatistics
Multi State Models
Ordinal Data

Multi-State-Markov (MSM) models can be used to characterize the behaviour of categorical outcomes measured repeatedly over time. Kalbfleisch and Lawless (1985) and Gentleman et al. (1994) examine the MSM model under the assumption of time-homogeneous transition intensities. In the context of non-homogeneous intensities, current methods use piecewise constant approximations which are less than ideal. We propose a local likelihood method, based on Tibshirani and Hastie (1987) and Loader (1996), to estimate the transition intensities as continuous functions of time. In particular the local EM algorithm suggested by Betensky et al. (1999) is employed to estimate the in-homogeneous intensities in the presence of missing data. A simulation comparing the piecewise constant method with the local EM method is examined using two different sets of underlying intensities. In addition, model assessment tools such as bandwidth selection, grid size selection, and bootstrapped percentile intervals are examined. Lastly, the method is applied to an HIV data set to examine the intensities with regard to depression scores. Although computationally intensive, it appears that this method is viable for estimating non-homogeneous intensities and outperforms existing methods.
"To Make the Negro Anew"; The African American Worker in the Progressive Imagination 1896-1928
Keywords: African American
Progressivism
Labor
World War One
Evolution
Scientific Management

This dissertation examines how progressive era social scientists thought about African American workers and their place in the nation’s industrial past, present, and future.Progressives across the color line drew on a common discourse of industrial evolution that linked racial development with labor fitness. Evolutionary science merged with scientific management to create new taxonomies of racial labor fitness. I chart this process from turn of the century actuarial science which defined African Americans as a dying race, to wartime mental and physical testing that acknowledged the Negro as a vital -albeit inferior- part of the nation’s industrial workforce. During this period, African Americans struggled to prove their worth on the shop-floor, the battlefield, and the academy. This thesis contends that the modern Negro type- African Americans as objects of social scientific inquiry- which came of age in the post-World War Two era, was born in the draft boards, factories, trenches, hospitals, and university classrooms of the Progressive Era.
Understanding and Changing the Patient Safety Culture in Canadian Hospitals
Keywords: patient safety culture
organizational culture
organizational culture change
patient safety culture measurement

Patient safety experts identify changes in culture as critical to creating safer care (Flin, 2007; Leape, 1994; Reason, 1997; Vincent, Taylor-Adams & Stanhope, 1998). Yet there is limited understanding of how to best study, evaluate and make changes to patient safety culture. The literature on organizational culture, safety sciences and health services research suggests varying perspectives on studying culture and an evolving approach to creating tools to measure culture change. This thesis reports two projects. The first project used the Manchester Patient Safety Culture Assessment Tool, the Modified Stanford Instrument, and qualitative interviews to examine whether safety culture profiles varied by research method and instrument used to assess culture. Comparative assessment of the results suggests that while the quantitative measurement tools provide a high level organizational summary of safety issues, the qualitative interviews provide a more fine-grained understanding of the contextual and local features of the culture. The second research project used a multiple case study design to understand what hospitals have learned from trying to improve patient safety culture. Interviews in three organizations were used to determine how these organizations shifted their cultures. Although each organization had different experiences and used varying methods, they all created culture change through the simultaneous implementation of practice, policies and strategic framing of patient safety culture concepts in their everyday work. The third research paper examined how leaders measured changes in patient safety culture. Both leaders and front line workers look to both process measures (e.g., talking about safety and encouraging patient safety activities) together with outcome measures (e.g., adverse events, infection rates, and culture survey results) to evaluate their success in culture change. Overall this dissertation deepens our knowledge of how methods influence our assessment of patient safety culture and how leaders influence culture change. Future research needs to assess in more detail the roles of leaders and middle managers to understand how these individuals are able to reconcile the practice environment challenges while continuing to create a culture of patient safety.
Real Robustness Radii and Performance Limitations of LTI Control Systems
Keywords: control systems
linear time-invariant systems
robustness radius
performance limitation

In the study of linear time-invariant systems, a number of definitions, such as controllability, observability, not having decentralized fixed modes, minimum phase, etc., have been made. These definitions are highly useful in obtaining existence results for solving various types of control problems, but a drawback to these definitions is that they are binary, which simply determines whether a system is, for instance, either controllable or uncontrollable. In practical situations, however, there are many uncertainties in a system’s parameters caused by linearization, modelling errors, discretizations, and other numerical approximations and/or errors. So knowing that a system is controllable can sometimes be misleading if the controllable system is actually "almost" uncontrollable as a result of such uncertainties. Since an "almost" uncontrollable system poses significant difficulty in designing a quality controller, a continuous measure of controllability, called a controllability radius, is more desirable to use and has been widely studied in the past. The main focus of this thesis is to extend the development behind the controllability radius, with an emphasis on real parametric perturbations, to other definitions, replacing the traditional binary 'yes/no' metrics with continuous measures. We study four topics related to this development. First, we generalize the concept of real perturbation values of a matrix to the cases of matrix pairs and matrix triplets. By doing so, we are able to deal with more general perturbation structures and subsequently study, in addition to standard LTI systems, other types of systems such as LTI descriptor and time-delay systems. Second, we introduce the real decentralized fixed mode (DFM) radius, the real transmission zero at s radius, and the real minimum phase radius, which respectively measure how "close" i) a decentralized LTI system is to having a DFM, ii) a centralized system is to having a transmission zero at a particular point s in the complex plane, and iii) a minimum phase system is to being a nonminimum phase system. These radii are defined in terms of real parametric perturbations, and computable formulas for these radii are derived using a characterization based on real perturbation values and the aforementioned generalizations. Third, we present two efficient algorithms to i) solve the general real perturbation value problem, and ii) evaluate the various real LTI robustness radii introduced in this thesis. Finally as the last topic, we study the ability of a LTI system to achieve high performance control, and characterize the difficulty of achieving high performance control using a new continuous measure called the Toughness Index. A number of examples involving the various measures are studied in this thesis.
On the JLO Character and Loop Quantum Gravity
Keywords: noncommutative geometry
quantum gravity
mathematical physics

In type II noncommutative geometry, the geometry on a C∗-algebra A is given by an unbounded Breuer–Fredholm module (ρ,N,D) over A. Here ρ:A→N is a ∗-homomorphism from A to the semi-finite von Neumann algebra N⊂B(H), and D is an unbounded Breuer–Fredholm operator affiliated with N that satisfies certain axioms. Each Breuer–Fredholm module assigns an index to a given element in the K-theory of A. The Breuer–Fredholm index provides a real-valued pairing between the K-homology and the K-theory of A. When N=B(H), a construction of Jaffe-Lesniewski-Osterwalder associates to the module (ρ,N,D) a cocycle in the entire cyclic cohomology group of A for D is theta-summable. The JLO character and the K-theory character intertwine the K-theoretical pairing with the pairing of entire cyclic theory. If (ρ,N,F) is a finitely summable bounded Breuer–Fredholm module, Benameur-Fack defined a cocycle generalizing the Connes's cocycle for bounded Fredholm modules. On the other hand, given a finitely-summable unbounded Breuer–Fredholm module, there is a canonically associated bounded Breuer–Fredholm module. The first main result of this thesis extends the JLO theory to Breuer–Fredholm modules (possibly N does not equal B(H)) in the graded case, and proves that the JLO cocycle and Connes cocycle define the same class in the entire cyclic cohomology of A. This extends a result of Connes-Moscovici for Fredholm modules. An example of an unbounded Breuer–Fredholm module is given by the noncommutative space of G-connections due to Aastrup-Grimstrup-Nest. In their original work, the authors limit their construction to the case that the group G=U(1) or G=SU(2). Another main result of the thesis extends AGN’s construction to any connected compact Lie group G; and generalizes by considering connections defined on sequences of graphs, using limits of spectral triples. Our construction makes it possible to equip the module (ρ,N,D) with a Z_2-grading. The last part of this thesis studies the JLO character of the Breuer–Fredholm module of AGN. The definition of this Breuer–Fredholm module depends on a divergent sequence. A concrete condition on possible perturbations of the sequence ensuring that the resulting JLO class remains invariant is established. The condition implies a certain functoriality of AGN’s construction.
The Neurophysiological Correlates of Children's and Adults' Judgments of Moral and Social Conventional Violations
Keywords: Moral development
Social conventions
Neuroscience
ERP
N2

Adults and young children have been found to distinguish between moral and social conventional acts, which are considered to entail distinct domains of reasoning (e.g., Turiel 1983). Recently, research has begun to examine the neural basis of moral judgments (e.g., Greene et al., 2001), but these studies did not examine the development of neurocognitive processing of judgments in these two domains. The present study focused on detection of cognitive conflict as a neurocognitive process that distinguished judgments of moral and conventional violations. The N2 component of the ERP was examined in order to determine whether the two types of violation are associated with different neurophysiological correlates and whether they change with development. In a series of five experiments, reaction times and ERPs were recorded from 12- to 14-year-old children and undergraduates who read scenarios that had one of three possible endings: (1) moral violations, (2) conventional violations, (3) no violation (neutral acts). Participants judged whether the act was acceptable or unacceptable when a rule was assumed or removed. Results indicate that reaction times were faster for moral than conventional violations when a rule was assumed for both undergraduates and children, as well as when a rule was removed for children but not for undergraduates. ERP data indicated that adults’, but not children’s, N2 amplitudes were larger (i.e., more negative) for conventional than iii moral violations when a rule was assumed. Furthermore, source analysis indicated generators for the N2 in dorsomedial and ventromedial prefrontal cortices. The results suggest that judgments of conventional violations involve increased conflict detection as compared to moral violations, and these two domains are processed differently across development. The findings were explained by the idea that judgments of conventional violations are more explicitly dependant on rules, whereas judgments of moral violations are based more directly on the intrinsic negative consequences of the act.
Exploring Many-body Physics with Ultracold Atoms
Keywords: ultracold atoms
many-body physics
Bose-Einstein condensate
quantum degeneracy
ferromagnetism
Josephson effects

The emergence of many-body physical phenomena from the quantum mechanical properties of atoms can be studied using ultracold alkali gases. The ability to manipulate both Bose-Einstein condensates (BECs) and degenerate Fermi gases (DFGs) with designer potential energy landscapes, variable interaction strengths and out-of-equilibrium initial conditions provides the opportunity to investigate collective behaviour under diverse conditions. With an appropriately chosen wavelength, optical standing waves provide a lattice potential for one target species while ignoring another spectator species. A “tune-in” scheme provides an especially strong potential for the target and works best for Li-Na, Li-K, and K-Na mixtures, while a “tune-out” scheme zeros the potential for the spectator, and is pre- ferred for Li-Cs, K-Rb, Rb-Cs, K-Cs, and 39K-40K mixtures. Species-selective lattices provide unique environments for studying many-body behaviour by allowing for a phonon-like background, providing for effective mass tuning, and presenting opportunities for increasing the phase-space density of one species. Ferromagnetism is manifest in a two-component DFG when the energetically preferred many-body configuration segregates components. Within the local density approximation (LDA), the characteristic energies and the three-body loss rate of the system all give an observable signature of the crossover to this ferromagnetic state in a trapped DFG when interactions are increased beyond kF a(0) = 1.84. Numerical simulations of an extension to the LDA that account for magnetization gradients show that a hedgehog spin texture emerges as the lowest energy configuration in the ferromagnetic regime. Explorations of strong interactions in 40K constitute the first steps towards the realization of ferromagnetism in a trapped 40K gas. The many-body dynamics of a 87Rb BEC in a double well potential are driven by spatial phase gradients and depend on the character of the junction. The amplitude and frequency characteristics of the transport across a tunable barrier show a crossover between two paradigms of superfluidity: Josephson plasma oscillations emerge for high barriers, where transport is via tunnelling, while hydrodynamic behaviour dominates for lower barriers. The phase dependence of the many-body dynamics is also evident in the observation of macroscopic quantum self trapping. Gross-Pitaevskii calculations facilitate the interpretation of system dynamics, but do not describe the observed damping.
The Need for a Physical Education: Examining Physical Activity During The Transition to University
Keywords: Physical Activity
Transition

While physical activity (PA) declines across the lifespan, this does not occur linearly. Declines are most pronounced during the transition into early adulthood. This dissertation consisted of three studies examining PA decline during the transition into early adulthood: (1) to understand patterns of PA and other health behaviours of Canadians; (2) to understand reasons for PA declines during entry into university; and (3) to examine the feasibility and effects of a website-delivered PA intervention. Study 1 utilized multilevel modeling to identify patterns of PA, binge drinking and smoking among a nationally-representative cohort of adolescents (N = 640). Results found PA decline evident among all young adults transitioning into early adulthood regardless of educational trajectory – declines being most pronounced among college/university males – highlighting the saliency of PA decline, as other health behaviours stabilized or declined during early adulthood. Given justification for intervening with the university population, study 2 explored students’ perceptions of PA, and their preferences towards a PA intervention. Eight focus groups were conducted with first-year university students (N = 45). Results found students being concerned with PA decline, and were receptive to an Internet-based intervention. However, such concerns are inflected with ambivalence, potentially posing a challenge for interventionists. Findings from studies 1 and 2 informed the development of a website-delivered PA intervention – ‘Active Transition’. Pre-testing was conducted with first-year students (N = 15) and PA experts (N = 7), which found the website and its content being acceptable and usable. Results of the efficacy trial (N = 65) found Active Transition to successfully attenuate declines in PA cognitions, and to some extent, PA behaviours. This confirms the Internet being a useful tool for delivering PA interventions in this population. However, given modest compliance in terms of usage, future work is required to evaluate the addition of more current/popular strategies for engaging students. Overall, this dissertation has provided justification for why it is critical that research continues work with this population, and has provided the foundations in helping with the long-term vision of implementing a population-level initiative to help students attenuate the significant declines in their PA behaviours.
Prediction of Protein-protein Interactions and Essential Genes through Data Integration
Keywords: protein-protein interactions
data mining

The currently known network of human protein-protein interactions (PPIs) is providing new insights into diseases and helping to identify potential therapies. However, according to several estimates, the known interaction network may represent only 10% of the entire interactome - indicating that more comprehensive knowledge of the interactome could have a major impact on understanding and treating diseases. The primary aim of this thesis was to develop computational methods to provide increased coverage of the interactome. A secondary aim was to gain a better understanding of the link between networks and phenotype, by analyzing essential mouse genes. Two algorithms were developed to predict PPIs and provide increased coverage of the interactome: FpClass and mixed co-expression. FpClass differs from previous PPI prediction methods in two key ways: it integrates both positive and negative evidence for protein interactions, and it identifies synergies between predictive features. Through these approaches FpClass provides interaction networks with significantly improved reliability and interactome coverage. Compared to previous predicted human PPI networks, FpClass provides a network with over 10 times more interactions, about 2 times more proteins and a lower false discovery rate. This network includes 595 disease related proteins from OMIM and Cancer Gene Census which have no previously known interactions. The second method, mixed co-expression, aims to predict transient PPIs, which have proven difficult to detect by computational and experimental methods. Mixed co-expression makes predictions using gene co-expression and performs significantly better (p < 0.05) than the previous method for predicting PPIs from co-expression. It is especially effective for identifying interactions of transferases and signal transduction proteins. For the second aim of the thesis, we investigated the relationship between gene essentiality and diverse gene/protein features based on gene expression, PPI and gene co-expression networks, gene/protein sequence, Gene Ontology, and orthology. We identified non-redundant features closely associated with essentiality, including centrality in PPI and gene co-expression networks. We found that no single predictive feature was effective for all essential genes; most features, including centrality, were less effective for genes associated with postnatal lethality and infertility. These results suggest that understanding phenotype will require integrating measures of network topology with information about the biology of the network’s nodes and edges.