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Towards Trustworthy AI: Investigating Bias and Confidence Alignment in Large Language Models
Get PDFLLMs are increasingly integrated into critical fields such as healthcare, judiciary, education, etc, thoroughly evaluating their trustworthiness is becoming ever more essential. This research thesis presents a unified examination of two critical aspects
of trustworthiness in LLMs: their self-evaluation of confidence and the subtler biases that shape their outputs. In the first part, we introduce the concept of Confidence Probability Alignment to scrutinize how LLMs’ internal confidence, indicated by token probabilities, aligns with the confidence they express when queried about their certainty. This analysis is enriched by employing diverse datasets and prompting techniques aimed at encouraging model introspection, such as structured evaluation
scales and the inclusion of answer options. Notably, OpenAI’s GPT-4 emerges as a leading example, demonstrating strong confidence-probability alignment, signifying a step towards understanding and improving LLM reliability. Conversely, the second part addresses the nuanced biases LLMs exhibit towards specific social narratives and identities, introducing the Representative Bias Score (RBS) and the Affinity Bias Score (ABS) to quantify these biases. Our exploration into representative and affinity biases through the Creativity-Oriented Generation Suite (CoGS) reveals a pronounced preference in LLMs for outputs reflecting the
experiences of predominantly white, straight, and male identities. This trend not only mirrors but potentially exacerbates societal biases, highlighting a complex interaction between human and machine bias perceptions
An Act for erecting a Suspension Bridge over the Niagara River, at or near the Falls of Niagara, 1846
Get PDFIn 1846, the governments of Upper Canada and the State of New York initiated the creation of two companies that would be authorized to build a bridge over the Niagara River. The bridge was to be owned by both companies, respectively known as the Niagara Falls Suspension Bridge Company (Canadian) and the International Bridge Company (American). Engineer Charles Ellet was hired to construct the bridge and completed a temporary suspension bridge that opened in 1848. A financial dispute with the Bridge Companies led to Ellet’s departure and American civil engineer John A. Roebling was hired in 1851. He was to build a suspension bridge that would carry railways and carriages. In 1854 a lower deck was completed and opened to carriages and pedestrians. The following year the upper deck was opened which carried railway cars. It became the first working suspension railway bridge in history and remained in operation until 1897.A document titled “Anno Decimo Victoria Reginae, Cap. CXII [1846, No. 112]: An Act for erecting a Suspension Bridge over the Niagara River, at or near the Falls of Niagara”. The document is four pages and includes sections on incorporation, amount of capital, management, stock, meetings, site survey, tolls and penalties, and the construction timeline. The names of the principal investors are listed and include Samuel De Veaux, James Buchanan, Thomas Street, C.B. Stuart, P. Whitney, W.H. Merritt, James Cummings, Oliver T. Macklim, James R. Benson, and William Wright. Royal Assent was given by Her Majesty in Council on 30th October [1846], and proclamation made thereof by His Excellency Earl Cathcart, in the Canada Gazette of December 26, 1846
Developmental changes in motor unit activity patterns: child-adult comparison using discrete motor unit analysis
Get PDFUsing global surface electromyography (sEMG) and the sEMG threshold it has been suggested that children activate their type-II motor unit (MU) to a lesser extent compared with adults. However, when age-related differences in discrete MU activation are examined using sEMG decomposition this phenomenon is not observed. Furthermore, findings from these studies are inconsistent and conflicting. Therefore, the purpose of this study was to examine differences in discrete MU activation of the vastus lateralis (VL) between boys and men during moderate-intensity knee extensions. Seventeen boys and 20 men completed two laboratory sessions. Following a habituation session, maximal voluntary isometric knee extension (MVIC) torque was determined before completing trapezoidal contractions at 70% MVIC. sEMG of the VL was captured and mathematically decomposed into individual MU action potential trains. Motor unit action potential amplitude (MUAPamp), recruitment threshold (RT), and MU firing rates (MUFR) were calculated. We observed that MUAPamp–RT slope was steeper in men compared with boys (p < 0.05) even after accounting for fat thickness and quadriceps muscle depth. The mean MUFR and y-intercept of the MUFR–RT relationship were significantly (p < 0.001) lower in boys than in men. The slope of the MUFR–RT relationship tended to be steeper in men, but the differences did not reach statistical significance (p = 0.056). Overall, our results suggest that neural strategies used to produce torque are different among boys and men. Such differences may be related, in part, to boys’ lower MUFR and lesser ability to activate their higher-threshold MUs. Although, other factors (e.g., muscle composition) likely also play a role.Natural Sciences and Engineering Research Council of Canad
Empowering New Beginnings: A Holistic Evaluation of a Community-Developed Multi-Sports Program for New-to-Canada Refugee Youths and Its Impact on Physical Literacy, Mental Wellbeing, and Social Health
Get PDFResettlement for refugee youth in Canada presents multifaceted challenges, notably in integrating into existing social structures, including sports and physical activity (PA) programs. Sports and PA programs can play a crucial role in promoting physical and mental well-being, yet refugee youth often face lower participation rates compared to their Canadian-born counterparts. To address this gap, this study investigated the impact of a community-developed multi-sport program, the Calgary Catholic Immigration Society (CCIS) multi-sport program, on the physical literacy (PL) development and psychosocial well-being of young refugees in Calgary, Canada. The program aimed to equip refugee youth with the tools to embrace sports and PA opportunities in their new environment, fostering physical well-being and a sense of belonging. A total of 16 refugee youth participants between the ages of 13-19 years old (Mage = 16.00±1.75, n =14 males) were recruited for this study and were living in temporary housing (M = 1.19 months on arrival) while being assisted by CCIS during their resettlement period. The study employed mixed methods, including the PLAYbasic tool and a modified PLAYself questionnaire, to assess program effects on various PL domains. Qualitative data from focus group interviews and an ethnographic approach provided further insights into the program's broader impact on well-being and social health. The findings revealed positive changes, particularly for those who participated frequently. The program improved their fundamental movement skills, boosted their confidence, and influenced their motivation to participate in sports and PA. More importantly, the program fostered social connections and a sense of belonging, contributing positively to their mental well-being. Participants also benefitted from access to well-equipped facilities, structured programs with qualified coaches, and valuable resources within the community. However, challenges remain. Logistical difficulties like competing schedules and lack of awareness about the program hindered consistent participation. Additionally, gender disparities emerged, with female participants highlighting the need for privacy and female-specific programming. This study highlights the value of community-developed, culturally sensitive sports programs. Such programs can effectively promote PL development, social integration, and overall well-being among refugee youth. Future research should explore the program's long-term effects and address specific barriers that prevent female participation
The use of immobilized caffeine aptamers in decaffeination & Roles of co-precipitants in the precipitation of DNA
Get PDFWith the growing consumption of decaffeinated beverages, the development of eco-friendly and cost-effective methods to achieve decaffeination has been a growing field within the biotechnology industry. This thesis investigated the selection of a caffeine-specific aptamer through in-vitro selection. Using immobilized targets of caffeine and theophylline, and capped immobilized targets of caffeine and heptanoic acid, a library of caffeine-specific aptamers was obtained. Illumina sequencing was utilized to obtain sequences of the resulting aptamer pool with two sequences, N-12 and N-13-1, being selected for further characterization. Preliminary isothermal titration calorimetric experiments showed weak binding to caffeine. Future work will examine the binding of these two sequences and other potential sequencies in detail.
DNA precipitation protocols are an integral part of many biotechnology and molecular biology laboratory procedures. When precipitating samples of low concentrations, co-precipitants are typically used to help facilitate the precipitation process. In this study, the validation of using co-precipitants in DNA precipitation protocols was conducted. Three carbohydrate-based co-precipitants, glycogen, dextran and β-glucan at concentrations of 20 mg/mL were tested to determine the optimal conditions for
DNA recovery through precipitation with no clear improvements in DNA precipitation being reported. Additionally, the effects of co-precipitants on DNA duplex formation, as investigated using circular dichroism, was found to be minimal with no notable differences. Furthermore, the potential interferences of co-precipitants on B-DNA to Z-DNA transitions were investigated using circular dichroism. It was found that the use of co-precipitants does not have significant effects on Z-DNA transitions. On the other hand, some changes in the circular dichroism of B-DNA were observed in the presence of glycogen and dextran. Future work will explore these conformations changes
Towards the total synthesis of semi-synthetic opiate species and presilphiperfolan-1-ol.
Get PDFThe synthesis of 10-keto opiates is underscored by the urgent need of novel κ-selective opioid agonists that offer comparable analgesic effects to their alkaloid precursors while limiting the risks of physical dependency. While there have been multiple syntheses of oxycodone reported, there has been only one total synthesis of 10-keto-oxycodone to date. Inspired by previous work from the Fukuyama group we investigated a functional group-based approach to oxycodone and 10-keto-oxycodone highlighted by a key oxidative dearomatization step. Efforts made towards this end with be discussed herein.
Presilphiperfolanols constitute a family of sesquiterpenes that can undergo further rearrangement to afford a diverse array of terpenoid skeletons due to the ring strain that is inherent to their carbocyclic framework. This structurally complex family of natural products is unique owing to their highly compact tricyclo[5.3.1.04,11]undecane sesquiterpene skeleton that bears five contiguous stereocenters, two all-carbon quaternary centers, and a tertiary hydroxy group. To date, only three natural presilphiperfolanols have been isolated: presilphiperfolan-1β-ol, presilphiperfolan-8α-ol, and presilphiperfolan-9α-ol. In addition to being important biosynthetic precursors, these natural products have also been found to exhibit antimicrobial activity and insecticidal properties. Of particular interest is presilphiperfolan-1β-ol, which has been previously synthesized by Stoltz in the first asymmetric synthesis of a presilphiperfolanol, and subsequently by Tiefenbacher in a semi-synthesis involving supramolecular catalysis. Unlike the approaches by Stoltz and Tiefenbacher, our group has discovered a highly efficient tandem gold (I) catalyzed 5-exo-dig and formal [4+2] cyclization that affords direct access to this tricyclo[5.3.1.04,11]undecane sesquiterpene skeleton. This method has the added benefit of generating 3 of the 5 requisite stereocenters found within the target in a single transformation. Efforts towards the completion of the total synthesis of presilphiperfolan-1-ol will be discussed herein. Experimental and spectral data are provided for all newly synthesized compounds
Time Series Prediction: HMMs with TAN and Bayesian Network Observation Structures
Get PDFThis thesis addresses key challenges in time series classification, focusing on enhancing predictive ac curacy through innovative modeling techniques. First, we introduce TAN-HMM, an extension of the
traditional Hidden Markov Model (HMM) that incorporates Tree-Augmented Naive Bayes (TAN) to ac count for correlated features, significantly improving classification performance on complex datasets like
MSRC-12. Next, we propose the Bayesian Network Hidden Markov Model (BN-HMM), which com bines the temporal dynamics of HMMs with the structural flexibility of Bayesian Networks, achieving
superior accuracy and feature relationship discovery. Finally, we tackle the problem of robust early warn ing signals for disease outbreaks, utilizing cutting-edge deep learning models to predict emerging disease
behavior from simulated and real-world noisy datasets. Together, these contributions push the boundaries
of time series classification and offer practical solutions for real-world applications, from human activity
recognition to disease outbreak prediction
Resisting Neoliberal, Adultist and Ableist Education: An Autoethnography of a Deschooling Parent
Get PDFDeploying a Foucauldian reading of autoethnography, this dissertation examines how deschooling can be used to resist discourses of neoliberalism, adult supremacy and ableism in education. Using a series of descriptive vignettes written to my family, I present my story as a deschooling parent that begins with my children’s exit from school during the Covid-19 pandemic and spans through their return three years later. The memories I describe in these vignettes were selected from family interviews and are framed as reflexive responses to our discussions. I analyse the narratives presented in these vignettes in terms of my research questions: 1) How does my parenting constitute a form of deschooling from below that resists neoliberalism and neoliberal privilege? and 2) How does my parenting approach differ from the adultist and ableist forms of education I critique in this dissertation? I discuss how my experiences helped me challenge the binary between deschooling and schooling and thus concentrate on how to use my subjectivity as a parent to resist neoliberal, adultist and ableist education in all the contexts in which my children find themselves including their home lives. My discursive intervention as a parent has primarily been in the lives of my children, myself and my family, but I also have the hope that it will shift power, discourse and subjectivity in ways that have wider reaching deschooling effects
The Wooded Weald: Private Woodland Management and England's 'Timber Famine', 1680-1790.
Get PDFEarly modern England was a world of wood. Everyone from laity to elite had a vested interest in woodland resources because it was a necessity for all aspects of life from warmth, fuel, shelter, transportation, and industry. Starting in the late fifteenth century and lasting through the early modern period, anxieties about timber scarcity spread as the Royal Navy complained of shortages. Since the Royal Navy was responsible for the protection of the Kingdom and was an integral part of England’s colonial exploits abroad, the possibility that the maintenance of the fleet was at risk was cause for grave concern.
Through the late seventeenth and eighteenth centuries, the Royal Navy accused merchant ship builders, agriculturalists, woodland industrialists, and private woodland owners of fomenting shortages through careless destruction of woodlands for profit, leading to a “timber famine”. Although most naval timber that furnished the Royal Navy came from private estates, historians have focussed on management in the Royal Forests. This thesis investigates how private woodland owners in the Weald, who owned most of the wood and timber reserves in southeast England managed their most essential resource. Private landowners’ interests directly conflicted with the interests of the Royal Navy, yet ultimately it was not the landowners who were responsible for perceived timber shortages. However, an inability to reconcile these competing interests contribute to historic myths about the state of England’s woodlands in the early modern period.
Through an in-depth HGIS (Historical Geographic Information System) study, this thesis argues that private landowners in the Weald were motivated by profit to sustainably maintain their woodlands. They chose to manage their woodlands with a preference for local underwood economies rather than timber because they were the most lucrative and thriving markets, much to the behest of the Royal Navy. I argue that the Royal Navy’s inability to procure timber during this period was due to lack of funds, disorganization within the Navy Board, and poor Royal Forest management which ultimately left them unable to keep up with the competitive timber market and provided more motivation for landowners to give preference to local underwood economies. Additionally, this thesis argues that timber scarcity in the Weald did not result in woodland destruction. In fact, the case study on Glassenbury demonstrates that Wealden landowners’ sustainable management was largely responsible for the maintenance of Wealden woods to this day
Understanding the Link Between Affinity for Solitude and Psychosocial Adjustment During Adolescence
Get PDFTime spent alone increases from childhood into adolescence. Some previous research suggests that solitude is a constructive experience, whereas other researchers argue that spending time alone may have negative implications for peer relationships during adolescence. Less is known about how different characteristics of solitude may be differentially associated with adjustment. The primary goals of my dissertation were 1) to explore whether the link between affinity for solitude and psychosocial adjustment depends on why or how often an adolescent spends time alone, 2) assess whether there are individual differences in patterns of attitudes towards solitude and experiences with solitude, and 3) identify when solitude is most associated with maladjustment during adolescence. Study 1 of my dissertation used a sample of early and mid- adolescents to examine whether affinity for solitude predicted psychosocial adjustment (i.e., depressive symptoms, social anxiety, peer victimization, friendship quality, self-esteem), controlling for previous scores on these indicators from two years earlier, and whether motivations for spending time alone (i.e., positive versus reactive) and frequency of time spent alone moderated this association. Study 2 used a person-centered approach to identify subgroups of adolescents who varied in characteristics of solitude and sociability, and then assessed whether there were group differences in earlier and concurrent psychosocial adjustment (i.e., depressive symptoms, social anxiety, peer victimization, friendship quality). Study 3 extended Study 2 to explore whether these groups of adolescents with different patterns of characteristics of solitude and sociability experienced changes in trajectories of psychosocial adjustment after the start of the COVID-19 pandemic, and whether the pandemic had a stronger effect for some groups compared to others. Overall, results indicated that affinity for solitude is relatively benign during adolescence, though this depends on why and how often adolescents spend time alone, as well as whether adolescents desire to be around others. Further, the implications of solitude may depend on contextual factors, such as the pandemic. Taken together, my dissertation highlights the importance of considering multiple characteristics of solitude, as well as sociability, to avoid broadly over pathologizing solitude during adolescence