VictorJuiz/thesis huggingface dataset:
New Message Passing Methods for Min-Max and Sum-Product Inference
Keywords: Combinatorial Optimization
Graphical Models
Inference
Message Passing

Message passing algorithms powered by the distributive law of mathematics are efficient in finding approximate solutions to NP-hard inference problems. This thesis proposes new message passing algorithms to enable and improve performance in two important modes of inference. First is min-max inference which seeks the assignment that minimizes the worse-case outcome. Examples include well known NP-hard combinatorial problems such as min-max clustering, the asymmetric K-center problem, K-packing, the bottleneck traveling salesman problem, and makespan minimization. Within min-max inference two algorithms are proposed. The first is Min-Max Propagation (MMP), a min-max version of Belief Propagation (BP) obtained by noting that min and max operators satisfy the distributive law. With MMP, it is shown that for any high-order function which can be minimized in O(ω), the message update can be computed using an efficient O(K(ω + log(K)) procedure, where K is the number of variables. The second algorithm reduces min-max inference to a sequence of Constraint Satisfaction Problems (CSPs). Both approaches perform well on NP-hard combinatorial problems. The second mode of interest is sum-product inference. Here, loopy BP performs poorly when the underlying mass contains multiple disjoint modes, capturing only one mode when it reaches a fixed point. As such, a message passing procedure that attempts to model all the fixed points of BP by defining a distribution over BP messages is considered; namely Survey Propagation (SP). Unfortunately SP is intractable beyond CSPs because, to perform general SP updates, one has to operate on distributions over a continuous domain. To efficiently extend the application of SP to marginalization in binary pairwise graphical models an approximation scheme is proposed. This scheme has O(DKlog(DK)τ ) complexity per iteration, where τ is the complexity of BP per iteration, D is the maximum node degree and K is a resolution constant controlling the approximations fidelity. Experiments show that this method can track many BP fixed points, achieving a high marginalization accuracy within a few iterations, in difficult settings where BP is often non-convergent and inaccurate.
How Do Expectations Influence Labour Supply? Evidence from Framed Field Experiments
Keywords: development
expectations
experiment
labour supply
reference dependent preferences
wages

Models of reference dependence have improved the connection between economic theory and documented labour supply behaviour. In particular, the Kőszegi and Rabin (2006, 2007, 2009) [hereafter "KR"] theory of expectation based reference dependent preferences appears to be a disciplined way to unify the conflicting wage elasticity estimates, and recent laboratory and natural experiments suggest this theory may work in practice as well. I take this theory to the field in a pair of laboratory-like experiments designed to test if expectations determine the effort of a group of impoverished individuals involved in piece-rate work in Northeast Brazil. I use Abeler, Falk, Goette, and Huffman's (2011) experimental mechanism, which is a clear test of KR preferences in effort provision, in two experiments: first to test if rational expectations act as a reference point that influences effort, and second to test if adaptive expectations act as a reference point that influences effort. In both experiments, I find that although people do not behave in accordance with KR preferences, they do not behave as though they make their decisions following canonical lines either. I then outline a speculative rationale for the observed behaviour in these experiments—the adaptive heuristic of regret matching—where workers are able to evaluate their ex-post feelings of regret, even if they do not know the source of those feelings, to optimize behaviour going forward.
Contextual Effects and Support for Liberalism: A Comparative Analysis
Keywords: Comparative politics
East Asia studies
Political sociology
Public opinion

This dissertation examines how variation in political freedom shapes individuals’ liberal attitudes and challenges existing explanations on value change. I begin by demonstrating that mainland China does not follow the path anticipated by Inglehart’s popular theory of value change, which expects protracted economic development to result in growing liberalism (Chapter 2). Many societies sharing similar economic and cultural backgrounds (such as Japan, South Korea, Hong Kong, Taiwan) have successfully embraced liberal values. I argue that it is necessary to consider a neglected contextual factor—level of political freedom—to explain the variation. I validate this argument by comparing a wide range of societies with different economic, cultural and political contexts in Chapter 3. My analysis shows that countries with different levels of political freedom exhibit markedly different patterns of value change. Specifically, while members of politically free societies largely follow the pattern sketched by Inglehart, relatively well-educated and well- to-do people in politically unfree societies experience little value change or even express growing conservativism (compared to other demographic groups) as their societies develop economically. To explain this finding, I suggest that political regimes, especially non-free regimes manipulate cultural institutions, including the educational system, to impede value liberalization. To investigate this process, Chapter 4 compares educational reform and value change in Taiwan and mainland China since the late 1940s. These two societies share economic and cultural backgrounds but have radically different political systems. My analysis finds that the value change mechanisms in the two societies differ greatly from each other. In sum, this dissertation demonstrates that political context is critically important in shaping individual value orientations. This argument adds to existing literature on how democratic values provoke democratization by emphasizing the other side of the story: how regimes, especially non- democratic ones, actively prevent value liberalization. The educational system is an important medium through which a political system promotes its preferred ideology. The main policy implication of this dissertation is that economic growth is insufficient to generate liberal values. Political freedom is a critical prerequisite for successful democratization and a healthy civil society.
Quantification of Changes in Vertebral Bone Quality in the Presence of Metastases
Keywords: Bone Quality
Metastases
Vertebra

Approximately 1/3 of all cancer patients suffer from spinal metastases. These metastases impact the equilibrium of the bone remodeling process, exhibiting excess bone-formation (osteoblastic), excess bone-resorption (osteolytic) or a mixture of the two. Previous work has assessed the impact of metastatic involvement on bone microarchitecture and mineral content, establishing relationships between these characteristics and mechanical behaviour. However, less well characterized are the effects of metastatic growth on the intrinsic features of the composite that is bone tissue. In combination with previously established methodologies to characterize the microarchitecture and mineral content of metastatic vertebrae, this work sought to utilize multiple imaging and analytical techniques to characterize the hydroxyapatite and collagen constituents of healthy and metastatic vertebral bone tissue from established athymic rat models of osteolytic and mixed vertebral metastases. Whole-bone measured changes were observed in collagen cross-linking and mineral crystal dimensions, within osteolytic vertebrae compared to healthy controls. Locally measured collagen organization and mineralization of bone tissue were found to be modified with metastatic involvement; with pathological osteoblastic new bone growth demonstrating stark differences compared to healthy controls. Tissue-level collagen features, assessed both globally (collagen cross-linking, proline concentration) and locally measured (collagen organization), were correlated to whole vertebral mechanical behaviour and the material level behaviour of bone tissue respectively. These changes in collagen cross-linking and organization, secondary to metastasis, were shown to significantly impact both tissue-level and whole vertebral mechanical behaviour independent of mineral content and bone microarchitecture. This work has created a robust characterization of the impact of metastasis on vertebral bone quality. As such, it provides a foundation from which it is possible to study the effects of treatments on metastatically-involved vertebral bone, which may ultimately improve the prediction of failure and direct treatment optimized to individual patients with spinal metastases.
Expanding the Limits of Vision-Based Autonomous Path Following
Keywords: Computer Vision
Field Robotics
Localization and Mapping

Autonomous path-following systems allow robots to traverse large-scale networks of paths using on-board sensors. These methods are well suited for applications that involve repeated traversals of constrained paths such as factory floors, orchards, and mines. Through the use of inexpensive, commercial, vision sensors, these algorithms have the potential to enable robotic applications across multiple industries. However, these applications will demand algorithms capable of long-term autonomy. This poses a difficult challenge for vision-based systems in unstructured and outdoor environments, whose appearances are highly variable. While techniques have been developed to perform localization across extreme appearance change, most are not suitable or untested for vision-in-the-loop systems such as autonomous path following, which requires continuous metric localization to keep the robot driving. This thesis extends the performance of vision-based autonomous path following through the development of novel localization and mapping techniques. First, we present the following generic localization frameworks: i) a many-to-one localization framework that combines data associations from independent sources of information into single state-estimation problems, and ii) a multi-experience localization and mapping system that provides metric localization to the manually taught path across extreme appearance change using bridging experiences gathered during autonomous operation. We use these frameworks to develop three novel autonomous path-following systems: i) a lighting-resistant system capable of autonomous operation across daily lighting change through the fusion of data from traditional-grayscale and color-constant images, ii) a multi-stereo system that extends the field-of-view of the algorithm by fusing data from multiple stereo cameras, and iii) a multi-experience system that uses both localization frameworks to achieve reliable localization across appearance change as extreme as night vs. day and winter vs. summer. These systems are validated through a collection of extensive field tests covering over 213 km of vision-in-the-loop autonomous driving across a wide variety of environments and appearance change with an autonomy rate of 99.7% of distance traveled.
Design, Implementation, and Operational Methodologies for Sub-Arcsecond Attitude Determination, Control, and Stabilization of the Super-pressure Balloon-borne Imaging Telescope (SuperBIT)
Keywords: attitude determination and control
balloon-borne telescopes
control systems engineering
diffraction limited imaging
high-resolution wide-field imaging
sub-arcsecond stability

Scientific balloon-borne instrumentation offers an attractive, competitive, and effective alternative to space-borne missions when considering the overall scope, cost, and development timescale required to design and launch scientific instruments. In particular, the balloon-borne environment provides a near-space regime that is suitable for a number of modern astronomical and cosmological experiments, where the atmospheric interference suffered by ground-based instrumentation is negligible at stratospheric altitudes. This work is centered around the analytical strategies and implementation considerations for the attitude determination and control of SuperBIT, a scientific balloon-borne payload capable of meeting the strict sub-arcsecond pointing and image stability requirements demanded by modern cosmological experiments. Broadly speaking, the designed stability specifications of SuperBIT coupled with its observational efficiency, image quality, and accessibility rivals state-of-the-art astronomical observatories such as the Hubble Space Telescope. To this end, this work presents an end-to-end design methodology for precision pointing balloon-borne payloads such as SuperBIT within an analytical yet implementationally grounded context. Simulation models of SuperBIT are analytically derived to aid in pre-assembly trade-off and case studies that are pertinent to the dynamic balloon-borne environment. From these results, state estimation techniques and control methodologies are extensively developed, leveraging the analytical framework of simulation models and design studies. This pre-assembly design phase is physically validated during assembly, integration, and testing through implementation in real-time hardware and software, which bridges the gap between analytical results and practical application. SuperBIT attitude determination and control is demonstrated throughout two engineering test flights that verify pointing and image stability requirements in flight, where the post-flight results close the overall design loop by suggesting practical improvements to pre-design methodologies. Overall, the analytical and practical results presented in this work, though centered around the SuperBIT project, provide generically useful and implementationally viable methodologies for high precision balloon-borne instrumentation, all of which are validated, justified, and improved both theoretically and practically. As such, the continuing development of SuperBIT, built from the work presented in this thesis, strives to further the potential for scientific balloon-borne astronomy in the near future.
Rare copy number variations associated with schizophrenia and intellectual disability
Keywords: 22q11.2
Cognitive
Copy number variation
Intellectual disability
NRXN1
Schizophrenia

Schizophrenia is a severe psychiatric disorder associated with significant impairments in cognitive functioning. Extensive evidence supports the importance of genetic aetiology, similar to other neurodevelopmental disorders like intellectual disability (ID). Of particular importance are large rare pathogenic copy number variations (CNVs), which have been independently associated with schizophrenia and ID. To date, there have been no studies systematically investigating the genome-wide burden and/or functional impact of rare CNVs on intellect (IQ) in schizophrenia. In this thesis, I used high resolution CNV data from a sample of 546 unrelated subjects of European descent with schizophrenia to investigate multiple IQ groups. The results demonstrated that the yield of pathogenic CNVs increased with decreasing IQ. Notably, the yield of pathogenic CNVs was similar for those with ID and those with a non-verbal learning disability (NVLD). There was a significantly greater burden of rare genic duplications that overlapped genes involved in neurodevelopment in individuals with schizophrenia in the lower IQ group compared to those with higher IQ that persisted after removing all subjects with a pathogenic CNV. I also investigated the variable expression and incomplete penetrance of two rare pathogenic CNVs by compiling every case with a 15q13.3 or a 3q13.31 microdeletion reported in the literature to date. The results of these studies showed ID and schizophrenia to be features of both, with the collective penetrance of 15q13.3 deletions for any neuropsychiatric disorder at over 80.0%. Finally, using two large clinically ascertained cohorts, I demonstrated that the burden of additional rare CNVs located elsewhere in the genome shapes the expression of schizophrenia in 22q11.2 deletion syndrome (22q11.2DS), and, together with the location of the deletion itself, the penetrance of ID in NRXN1 deletions. Collectively, these novel data represent important contributions towards understanding the genetic architecture of schizophrenia and ID.
The Myth of Stalingrad in Soviet Literature, 1942-1963
Keywords: Grossman
memory
myth
Soviet
Stalingrad
war

This study explores representations of the Battle of Stalingrad in Soviet literature between 1942 and 1963, asking how Stalingrad became central to Russian identity in this period. The work reads Stalingrad’s cultural significance within a body of scholarship on Soviet subjectivity and memory of the Second World War. My analysis begins with a survey of frontline newspaper stories, including material by Konstantin Simonov and previously unstudied stories by Vasily Grossman, which characterized the battle in eschatological terms. I then explore efforts to encode Stalingrad in epic form immediately following the battle and further chart how the story became a vehicle for Stalin’s deification in the late 1940s by comparing Il’ia Ehrenburg’s novel The Storm and minor works. I then show how Grossman’s For a Just Cause links wartime and Stalinist motifs. Finally, I uncover how Simonov and Grossman rewrote Stalingrad during the Khrushchev period. Simonov’s Not Born Soldiers suggested Stalingrad was a resurrection that could be repeated in the present; Grossman’s Life and Fate disrupted the epic wholeness of the Stalingrad myth with polyphony. Drawing on Frank Kermode’s work on myth, I read representations of Stalingrad as being imbued with kairotic significance for a Russian nation attached to an historicist view of the world. This sense of kairos encouraged readers to sublimate their sense of self with History. The victory’s “resurrection” of the nation provided the people and the regime with a new raison-d’être in the post-war years. For both, Stalingrad promised to resolve Soviet literature’s struggle to illustrate an epic present, and formed a shared identity around memory of the battle. I use Pierre Nora’s work on lieux de mémoire as an analytical framework to trace Stalingrad’s entry into national memory and the subsequent fluctuations in the battle’s representation throughout the wartime, Stalinist and Khrushchev-era presents. The flexibility and externality of the lieu as a means to preserve and recycle collective memory overcame contradictions inherent in the idea of experiencing kairos in the present. Whether invoked to deify or deconstruct Stalin, Stalingrad was the discursive centre for Soviet discussion of the past.
Hybridités génériques et discursives dans les Historiettes de Tallemant des Réaux
Keywords: Anecdotes
Fragments
Historiettes
Manuscrit
MĂŠdisance
Salons

Les Historiettes de Tallemant des Réaux ont été rédigées entre 1657 et 1659. Écrites à l’intention des amis, elles sont restées à l’état de manuscrit jusqu’à leur publication en 1834. Elles suscitent alors une véritable émotion et passionnent la critique. Leur auteur est traité de médisant et de calomniateur dont le bavardage de portier excite la curiosité d’une époque friande de scandales. Or, les Historiettes ne sont pas une simple consignation gratuite d’anecdotes juteuses. Tallemant médit non seulement pour « amuser la galerie », il cherche surtout à démasquer les impostures de la société dans laquelle il évolue. Le regard est ludique mais la mise en récit est sous-tendue par un dispositif rhétorique complexe. Au fil des ans, l’œuvre de Tallemant des Réaux a acquis ses lettres de noblesse. Elle est maintenant reconnue comme une des œuvres clé pour ceux qui s’intéressent au Grand-Siècle. Au-delà des informations que l’on y glane, c’est aussi le style du conteur et le ton facétieux qu’il adopte, ainsi que les multiples registres qui s’y entrecroisent, qui donnent au récit toute sa saveur. De la raillerie fine et mondaine qui adhère aux règles de civilité et de divertissement, à la satire qu'alimente une brutale obscénité, cet écrit à la forme éclatée repose sur une esthétique hybride et multiforme et offre un espace de lectures plurielles. Dans notre étude, nous avons surtout cherché à démontrer qu’en dépit des décalages de l’œuvre par rapport à l’écriture de l’histoire, et malgré des écarts esthétiques qui contreviennent aux règles d’un classicisme codifié reposant sur le sublime, les Historiettes n’en sont pas moins à la fois une œuvre historique et littéraire.
Troubling the Teacher Diversity Gap: The Perpetuation of Whiteness Through Practices of Bias Free Hiring in Ontario School Boards
Keywords: Colour-blindness
Equity
Inclusion
Leadership
Policy
Settler-colonialism

Teaching staff in Ontario schools do not reflect the increasing diversity of the students who occupy Ontario classrooms today. School boards across Ontario have come under considerable scrutiny regarding the lack of diverse teacher representation that adequately reflects Ontario’s demographic composition (Childs et al., 2010; Ryan, et al., 2009; Turner, 2015). This thesis addresses the Ontario teacher diversity gap (James Turner, 2017; Turner 2015; Turner, 2014; Ryan, et al., 2009) in relation to provincial equity and inclusive educational policies, which have been created to address the dominance of white teachers in publicly-funded education in Ontario. However, findings from the research indicate that these policies have not had the desired results, and in some ways have contributed to perpetuating the status quo, and the ongoing overrepresentation of white teachers in schools. The thesis furthermore addressed the notion of bias-free hiring (Fine Handlesman, 2012; Hassouneh, 2013) practices through narratives of Ontario teachers themselves. The predominant assumption of bias-free hiring is that one can divorce themselves from their unconscious biases and preconceptions of groups who are dissimilar to them in order to recruit the so-called “most qualified applicant”. The narrative of the “most qualified applicant” is a term invoked when racialized people seek access to employment opportunities. School administrators have great influence on who is hired; therefore it is important for administrators to interrogate their own social locations and positions of power, and unconscious bias in terms of how they recruit teachers. Findings from the research indicate that teachers from racialized groups have different experiences when seeking employment as teachers in publicly-funded school boards in Ontario. In response to this the EHT Equity Hiring Toolkit for Ontario School Administrators has been developed to support school administrators to recruit more diverse teachers. The EHT provides a framework for school administrators to engage in antiracist praxis and action, by examining their social location, and ways that their positionality impacts the hiring decisions they make. School administrators can use the creation of the Toolkit based on the findings of the data that emerged from the research as a Creative Professional Activity (CPA). I consider this to be my contribution to the field of social justice education and leadership.