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Grasp Based Metaheuristic To Solve The Mixed Fleet E-Waste Collection Route Planning Problem, Aldy Gunawan, Dang V.A. Nguyen, Pham K.M. Nguyen, Pieter. Vansteenwegen Aug 2023

Grasp Based Metaheuristic To Solve The Mixed Fleet E-Waste Collection Route Planning Problem, Aldy Gunawan, Dang V.A. Nguyen, Pham K.M. Nguyen, Pieter. Vansteenwegen

Research Collection School Of Computing and Information Systems

The digital economy has brought significant advancements in electronic devices, increasing convenience and comfort in people’s lives. However, this progress has also led to a shorter life cycle for these devices due to rapid advancements in hardware and software technology. As a result, e-waste collection and recycling have become vital for protecting the environment and people’s health. From the operations research perspective, the e-waste collection problem can be modeled as the Heterogeneous Vehicle Routing Problem with Multiple Time Windows (HVRP-MTW). This study proposes a metaheuristic based on the Greedy Randomized Adaptive Search Procedure complemented by Path Relinking (GRASP-PR) to solve …


The 4th International Workshop On Talent And Management Computing (Tmc'2023): Editorial, Hengshu Zhu, Hui Xiong, Yong Ge, Ee-Peng Lim Aug 2023

The 4th International Workshop On Talent And Management Computing (Tmc'2023): Editorial, Hengshu Zhu, Hui Xiong, Yong Ge, Ee-Peng Lim

Research Collection School Of Computing and Information Systems

In today's competitive and fast-evolving business environment, it is a critical time for organizations to rethink how to deal with the talent and management related tasks in a quantitative manner. Indeed, thanks to the era of big data, the availability of large-scale talent data provides unparalleled opportunities for business leaders to understand the rules of talent and management, which in turn deliver intelligence for effective decision making and management for their organizations. In the past few years, talent and management computing have increasingly attracted attentions from KDD communities, and a number of research/applied data science efforts have been devoted. To …


Vehicle Routing Problem With Parcel Locker And Public Transportation: Goods Delivery Using Mass-Rapid-Transit System, Pham K.M. Nguyen, Vincent F. Yu, Aldy Gunawan Aug 2023

Vehicle Routing Problem With Parcel Locker And Public Transportation: Goods Delivery Using Mass-Rapid-Transit System, Pham K.M. Nguyen, Vincent F. Yu, Aldy Gunawan

Research Collection School Of Computing and Information Systems

The logistics industry is experiencing significant transformations with the emergence of modern technologies, well-established civil infrastructure, and mixed transportation methods. These changes are driven by the increase in mobility, sustainability, and eco-friendliness of logistics processes. As a result, recent works have focused on incorporating mixed fleets and omnichannel systems to the original vehicle routing problem which boosts the delivery system's efficiency, effectiveness, reliability, and customer satisfaction while reducing operational costs simultaneously. We augment the existing studies by proposing a new mathematical model that combines common mass rapid transit systems and delivery fleets to solve the traditional vehicle routing problem with …


Sparsity Brings Vulnerabilities: Exploring New Metrics In Backdoor Attacks, Jianwen Tian, Kefan Qiu, Debin Gao, Zhi Wang, Xiaohui Kuang, Gang Zhao Aug 2023

Sparsity Brings Vulnerabilities: Exploring New Metrics In Backdoor Attacks, Jianwen Tian, Kefan Qiu, Debin Gao, Zhi Wang, Xiaohui Kuang, Gang Zhao

Research Collection School Of Computing and Information Systems

Nowadays, using AI-based detectors to keep pace with the fast iterating of malware has attracted a great attention. However, most AI-based malware detectors use features with vast sparse subspaces to characterize applications, which brings significant vulnerabilities to the model. To exploit this sparsityrelated vulnerability, we propose a clean-label backdoor attack consisting of a dissimilarity metric-based candidate selection and a variation ratio-based trigger construction. The proposed backdoor is verified on different datasets, including a Windows PE dataset, an Android dataset with numerical and boolean feature values, and a PDF dataset. The experimental results show that the attack can slash the accuracy …


Single-View View Synthesis With Self-Rectified Pseudo-Stereo, Yang Zhou, Hanjie Wu, Wenxi Liu, Zheng Xiong, Jing Qin, Shengfeng He Aug 2023

Single-View View Synthesis With Self-Rectified Pseudo-Stereo, Yang Zhou, Hanjie Wu, Wenxi Liu, Zheng Xiong, Jing Qin, Shengfeng He

Research Collection School Of Computing and Information Systems

Synthesizing novel views from a single view image is a highly ill-posed problem. We discover an effective solution to reduce the learning ambiguity by expanding the single-view view synthesis problem to a multi-view setting. Specifically, we leverage the reliable and explicit stereo prior to generate a pseudo-stereo viewpoint, which serves as an auxiliary input to construct the 3D space. In this way, the challenging novel view synthesis process is decoupled into two simpler problems of stereo synthesis and 3D reconstruction. In order to synthesize a structurally correct and detail-preserved stereo image, we propose a self-rectified stereo synthesis to amend erroneous …


Balancing Utility And Fairness In Submodular Maximization, Yanhao Wang, Yuchen Li, Francesco Bonchi, Ying Wang Aug 2023

Balancing Utility And Fairness In Submodular Maximization, Yanhao Wang, Yuchen Li, Francesco Bonchi, Ying Wang

Research Collection School Of Computing and Information Systems

Submodular function maximization is a fundamental combinatorial optimization problem with plenty of applications – including data summarization, influence maximization, and recommendation. In many of these problems, the goal is to find a solution that maximizes the average utility over all users, for each of whom the utility is defined by a monotone submodular function. However, when the population of users is composed of several demographic groups, another critical problem is whether the utility is fairly distributed across different groups. Although the utility and fairness objectives are both desirable, they might contradict each other, and, to the best of our knowledge, …


Multi-Granularity Detector For Vulnerability Fixes, Truong Giang Nguyen, Cong, Thanh Le, Hong Jin Kang, Ratnadira Widyasari, Chengran Yang, Zhipeng Zhao, Bowen Xu, Jiayuan Zhou, Xin Xia, Ahmed E. Hassan, David Lo, David Lo Aug 2023

Multi-Granularity Detector For Vulnerability Fixes, Truong Giang Nguyen, Cong, Thanh Le, Hong Jin Kang, Ratnadira Widyasari, Chengran Yang, Zhipeng Zhao, Bowen Xu, Jiayuan Zhou, Xin Xia, Ahmed E. Hassan, David Lo, David Lo

Research Collection School Of Computing and Information Systems

With the increasing reliance on Open Source Software, users are exposed to third-party library vulnerabilities. Software Composition Analysis (SCA) tools have been created to alert users of such vulnerabilities. SCA requires the identification of vulnerability-fixing commits. Prior works have proposed methods that can automatically identify such vulnerability-fixing commits. However, identifying such commits is highly challenging, as only a very small minority of commits are vulnerability fixing. Moreover, code changes can be noisy and difficult to analyze. We observe that noise can occur at different levels of detail, making it challenging to detect vulnerability fixes accurately. To address these challenges and …


A Comparative Study Of Vinti-Based Orbit Propagation And Estimation For Cubesats In Very Low Earth Orbits, Ethan Michael Senecal Aug 2023

A Comparative Study Of Vinti-Based Orbit Propagation And Estimation For Cubesats In Very Low Earth Orbits, Ethan Michael Senecal

Mechanical & Aerospace Engineering Theses & Dissertations

In recent years, there has been a growing interest in CubeSats and very low Earth orbit (VLEO) space missions. Mission SeaLion, a collaborative CubeSat mission between Old Dominion University, the U.S. Coast Guard Academy, and U.S. Air Force Institute of Technology, planned to launch a 3U CubeSat into VLEO. The VLEO mission is a particularly challenging environment for navigation and orbit propagation because drag introduces a significant perturbation for orbit models such as SGP4. Additionally, mission requirements left no capacity for attitude determination or control, further reducing knowledge of drag behavior of the satellite in flight. This deficiency is a …


Towards Intelligent Runtime Framework For Distributed Heterogeneous Systems, Polykarpos Thomadakis Aug 2023

Towards Intelligent Runtime Framework For Distributed Heterogeneous Systems, Polykarpos Thomadakis

Computer Science Theses & Dissertations

Scientific applications strive for increased memory and computing performance, requiring massive amounts of data and time to produce results. Applications utilize large-scale, parallel computing platforms with advanced architectures to accommodate their needs. However, developing performance-portable applications for modern, heterogeneous platforms requires lots of effort and expertise in both the application and systems domains. This is more relevant for unstructured applications whose workflow is not statically predictable due to their heavily data-dependent nature. One possible solution for this problem is the introduction of an intelligent Domain-Specific Language (iDSL) that transparently helps to maintain correctness, hides the idiosyncrasies of lowlevel hardware, and …


Deep Virtual Pion Pair Production, Dilini Lakshani Bulumulla Aug 2023

Deep Virtual Pion Pair Production, Dilini Lakshani Bulumulla

Physics Theses & Dissertations

This experiment investigates the deep virtual production of both σ− and ρ− mesons, with a particular focus on the microscopic structure of the σ mesons. While the ρ meson is an ordinary qq¯ pair, the σ meson is composed of not only the typical qq¯ pair, making it a topic of controversy for nearly six decades. Although the existence of the σ− meson is now well established, its microscopic structure remains poorly understood. The primary objective of this thesis is to contribute to the understanding of the σ meson by analyzing its deep virtual production. The main focus of this …


Chinese International Graduate Student Agency In A Neo-Racism Context: A Narrative Analysis, Minghui Hou Aug 2023

Chinese International Graduate Student Agency In A Neo-Racism Context: A Narrative Analysis, Minghui Hou

Educational Leadership & Workforce Development Theses & Dissertations

The United States is the top destination for Chinese international students, receiving around 372,532 students from China from the academic year 2019 to 2020. The host institutions and countries have benefited from economic gains, diverse cultures, global competence, and human capital. The motivation of recruiting international students is framed in a global imaginary that is embedded in colonialism and neoliberalism. International students are often framed as cash cows and objects. Meanwhile, international students, particularly Chinese international students have been experiencing discrimination, prejudice, and exclusion due to their nationality and culture. The purpose of this narrative inquiry study was to examine …


Multi-Dimensional Surface Water Quality Analyses In The Manawatu River Catchment, New Zealand, Imokhai T. Tenebe, Jason P. Julian, Praise God C. Emenike, Nathaniel Dede-Bamfo, Omeje Maxwell, Samuel E. Sanni, Eunice O. Babatunde, Darlan D. Alves Aug 2023

Multi-Dimensional Surface Water Quality Analyses In The Manawatu River Catchment, New Zealand, Imokhai T. Tenebe, Jason P. Julian, Praise God C. Emenike, Nathaniel Dede-Bamfo, Omeje Maxwell, Samuel E. Sanni, Eunice O. Babatunde, Darlan D. Alves

Faculty Research, Scholarly, and Creative Activity

Land Use and Land Cover (LULC) properties give vital information about pollution signatures in rivers, and they help develop best management practices (BMPs) for effective water resource management. This work employs multivariate statistical methods, receptor modeling, connectivity analysis, and univariate trend analysis to investigate pollution sources across spatiotemporal scales in the Manawatu River, New Zealand. A positive matrix factorization (PMF) method was applied to interpret possible contamination sources. A 25-year dataset (1989–2014) comprising 12 water quality variables from three sites was used. Runoff connectivity analyses identified high-producing grassland (HG) as the most dominant pollution class in all sub-catchments. Univariate analyses …


Global Energy Consumption: An Analysis Of Variables That Shape Per Capita Usage, Or How Pump Price, Urbanization, And Fossil Fuels Imports Impact Fossil Fuels Consumption Per Capita Across Oecd Countries, Mila Demchyk Savage Aug 2023

Global Energy Consumption: An Analysis Of Variables That Shape Per Capita Usage, Or How Pump Price, Urbanization, And Fossil Fuels Imports Impact Fossil Fuels Consumption Per Capita Across Oecd Countries, Mila Demchyk Savage

Graduate Program in International Studies Theses & Dissertations

Among reasons explaining the importance of studying fossil fuel consumption are: crude oil is a subject of the international commodities market, thus, any fluctuation related to its' availability or price would impact the rest of the World; natural resources like oil, gas, and coal are limited; the extensive use of fossil fuels harms our surroundings, creating many environmental concerns; every human (on average) has been using more energy since 1971 and the trend is expected to continue. The upward trend is not consistent among individual countries. Therefore, the core question of my research is, `Why do some countries consume less …


Mirror Position Detection In A Catoptric Surface, Run Zhang Aug 2023

Mirror Position Detection In A Catoptric Surface, Run Zhang

McKelvey School of Engineering Graduate Student Theses & Dissertations

The Catoptric Surface research project is a pioneering exploration of controlling daylight effects within built environments. In this thesis, we focus on the mirror position detection problem, which plays a vital role in achieving dynamic control over the direction of reflected light within a space. To address the challenge of mirror position detection, we employ computer vision techniques, specifically edge detection and the RANdom SAmple Consensus (RANSAC) algorithm. Edge detection is utilized to identify significant changes in intensity or color, corresponding to object boundaries, while RANSAC is applied for ellipse fitting. By iteratively selecting minimal subsets of points and fitting …


Mastering Stock Markets With Efficient Mixture Of Diversified Trading Experts, Shuo Sun, Xinrun Wang, Wanqi Xue, Xiaoxuan Lou, Bo An Aug 2023

Mastering Stock Markets With Efficient Mixture Of Diversified Trading Experts, Shuo Sun, Xinrun Wang, Wanqi Xue, Xiaoxuan Lou, Bo An

Research Collection School Of Computing and Information Systems

Quantitative stock investment is a fundamental financial task that highly relies on accurate prediction of market status and profitable investment decision making. Despite recent advances in deep learning (DL) have shown stellar performance on capturing trading opportunities in the stochastic stock market, the performance of existing DL methods is unstable with sensitivity to network initialization and hyperparameter selection. One major limitation of existing works is that investment decisions are made based on one individual neural network predictor with high uncertainty, which is inconsistent with the workflow in real-world trading firms. To tackle this limitation, we propose AlphaMix, a novel three-stage …


Generative Artificial Intelligence And Metaverse: Future Of Work, Future Of Society, And Future Of Humanity, Yuxin Liu, Keng Siau Aug 2023

Generative Artificial Intelligence And Metaverse: Future Of Work, Future Of Society, And Future Of Humanity, Yuxin Liu, Keng Siau

Research Collection School Of Computing and Information Systems

The rapid development of Generative Artificial Intelligence (GenAI) and the emergence of the Metaverse are dynamically reshaping our lives and societies. GenAI can enhance the development of Metaverse and empower the applications in Metaverse. Metaverse is also an excellent environment for GenAI to demonstrate its power and usefulness. This interwoven relationship fuels the potential of integrating GenAI and Metaverse. The paper discusses the integration potential of GenAI and Metaverse from four aspects. We further investigate how GenAI, Metaverse, and the integration of GenAI and Metaverse can reshape our future across the realms of work, society, and humanity. This paper offers …


Transformative Education: How Can You Become A Better College Teacher?, Joe Hoyle Aug 2023

Transformative Education: How Can You Become A Better College Teacher?, Joe Hoyle

Bookshelf

Transformative Education presents a comprehensive approach to college teaching that stresses both the presentation of topical coverage AND the development of critical thinking skills. The book focuses on several key points in the learning process such as student preparation for class, student engagement during class, and student review and organization of the material after class. The book discusses the urgent need for more and better high-quality college education, a goal that can be achieved by a methodical approach to gradual teaching improvement.


Two Essays On Investor Sentiment, Amin Amoulashkarian Aug 2023

Two Essays On Investor Sentiment, Amin Amoulashkarian

Theses and Dissertations in Business Administration

The body of literature on investor sentiment underlines its impact on future stock returns, with general consensus that investor sentiments and future returns are negatively correlated (Baker and Wurgler, 2006; Brown and Cliff, 2004). This extends to the notion that a bullish investor would expect returns to be above average, while a bearish investor anticipates below-average returns (Brown and Cliff, 2004).

The first essay proposes a model to examine the influence of unexpected volatility of investor sentiment on the equity risk premium. Assumptions underpinning the model include risk-averse investors, homogeneous expectations regarding asset returns and price changes, and sentiment-influenced expectations …


Generative Pre-Trained Transformers (Gpt) And Space Health: A Potential Frontier In Astronaut Health During Exploration Missions, Ethan Waisberg, Joshua Ong, Mouayad Masalkhi, Nasif Zaman, Sharif Amit Kamran, Prithul Sarker, Andrew G Lee, Alireza Tavakkoli Aug 2023

Generative Pre-Trained Transformers (Gpt) And Space Health: A Potential Frontier In Astronaut Health During Exploration Missions, Ethan Waisberg, Joshua Ong, Mouayad Masalkhi, Nasif Zaman, Sharif Amit Kamran, Prithul Sarker, Andrew G Lee, Alireza Tavakkoli

Faculty, Staff and Student Publications

In anticipation of space exploration where astronauts are traveling away from Earth, and for longer durations with an increasing communication lag, artificial intelligence (AI) frameworks such as large language learning models (LLMs) that can be trained on Earth can provide real-time answers. This emerging technology may be helpful for acute medical emergencies, particularly in austere and distant space environments. In this manuscript, we provide an overview of generative pre-trained transformer (GPT) technology, a rapidly emerging AI technology, and implications, considerations, and limitations of such technology for space health.


A Mixed Methods Examination Of First Year College Students: The Impact Of Ethnic Studies On Post-Secondary Education Experiences, Sherry Bell Aug 2023

A Mixed Methods Examination Of First Year College Students: The Impact Of Ethnic Studies On Post-Secondary Education Experiences, Sherry Bell

UNLV Theses, Dissertations, Professional Papers, and Capstones

Across the United States, fewer high school students are enrolling in university and completing university. Scholars have suggested that ethnic studies may positively influence student engagement and potentially increase university enrollment. This dissertation will discuss the literature related to ethnic studies and critical race theory in relation to frameworks that have been positively associated with student retention. The study described in this dissertation explored if ethnic studies taken prior to attending university is related to positive student experiences during university. The aims of the study were to (1) test the relationship between ethnic studies and positive student experiences (i.e., critical …


Teachers’ Relationship Ratings Of Adolescents With And Without The “Emotional Disturbance” Label, Ashley Colson Aug 2023

Teachers’ Relationship Ratings Of Adolescents With And Without The “Emotional Disturbance” Label, Ashley Colson

UNLV Theses, Dissertations, Professional Papers, and Capstones

The importance of student-teacher relationships is well established. However, research suggests that students in special education tend to experience lower quality student-teacher relationships than their peers in general education. Of particular importance is the developing research indicating that students with emotional and behavioral disorders (EBDs), and especially females, are at the highest risk of poor relationships with teachers. The purpose of this study is to examine whether the presence of an emotional disturbance (ED) label may impact teachers’ perceptions of relationships with adolescents who exhibit behavior that meets ED criteria. A correlational research design with a between-subjects analysis of the …


Principals’ Perceptions Of School Sponsored Field Trips, Melissa Suzanne Giannantonio Aug 2023

Principals’ Perceptions Of School Sponsored Field Trips, Melissa Suzanne Giannantonio

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this phenomenological study is to explore the views, attitudes, and ideas that school principals have on school-sponsored field trips. As society continues to change it is increasingly necessary to contemplate the growing significance of field trip facilities’ educational roles and garner “information about the audiences they serve” (Anderson et al., 2015, p. vii). Additionally, the past decade has seen a decline in the number of field trips taken by schools, and in 2020, field trips came to a complete halt due to COVID-19 (Center for Disease Control (CDC), 2020; Mathews, 2014; Mehta, 2008; Plummer, 2014; Reeves & …


Climatic Influences On Incipient Alteration In Mars-Relevant Ultramafic Soils, Anthony Feldman Aug 2023

Climatic Influences On Incipient Alteration In Mars-Relevant Ultramafic Soils, Anthony Feldman

UNLV Theses, Dissertations, Professional Papers, and Capstones

An ongoing debate exists around the nature of the climatic conditions present during the Noachian and early Hesperian periods (~4.1 to 3 Gyr ago) of Mars’ ancient history. The various theories put forward can reasonably be grouped into “warm and wet” vs “cold and icy” camps. Warm and wet approximates an Earth-like system with a relatively clement climate with significant liquid water present including potentially long-lived oceans. Cold and icy theories generally postulate thick ice sheets at high elevations with periodic warming events driving precipitation and the formation of river channels and leading to the formation of chemical alteration products. …


Synergy And Antagonism In Log-Linear Models, Md Nahid Hasan Aug 2023

Synergy And Antagonism In Log-Linear Models, Md Nahid Hasan

UNLV Theses, Dissertations, Professional Papers, and Capstones

Synergy and antagonism have been extensively studied in the context of the statistical analysis of drug combinations given to treat a disease. “Synergy” (“antagonism”, resp.) in a drug combination occurs when the desirable effect of two drugs given together for treating a disease is greater than (less than, resp.) the effect of each drug given separately.

In this dissertation, however, we study “synergy” and “antagonism” in log-linear models. We also give a thorough review and extend several epidemiological definitions of synergy and antagonism for categorical data, and we connect these definitions to the definitions of synergy and antagonism in log-linear …


Instructional Practices That Foster Argumentative Discourse In Secondary Science Classrooms, Alicia N. Herrera Aug 2023

Instructional Practices That Foster Argumentative Discourse In Secondary Science Classrooms, Alicia N. Herrera

UNLV Theses, Dissertations, Professional Papers, and Capstones

To remain competitive in an innovative world, American classrooms are promoting careers in science, technology, engineering, and mathematics (STEM) by utilizing the Next Generation Science Standards (NGSS). Students are engaged in inquiry by applying scientific practices like argumentation. However, science teachers are finding it difficult to respond to, as well as deepen students’ argumentative conversations. Therefore, research must uncover what instructional practices (or combinations) are used to overcome classroom obstacles, along with fostering students’ discourse and sensemaking. A teacher research approach was taken to investigate how the researcher, a secondary science teacher herself, effectively combines three under-researched instructional practices for …


Development Of Pre-Magnetized Magnetorheological Elastomer For Bidirectionally Variable Stiffness Applications, Choonghan Lee Aug 2023

Development Of Pre-Magnetized Magnetorheological Elastomer For Bidirectionally Variable Stiffness Applications, Choonghan Lee

UNLV Theses, Dissertations, Professional Papers, and Capstones

Magnetorheological elastomers (MREs) utilize magnetic forces between ferromagnetic particles to cause variable stiffness properties and damping with external magnetic fields. In the MREs, the particles are embedded in a cured elastomer matrix, and an external magnetic field makes the stiffness change due to induced magnetic forces among particles. A disadvantage of the conventional MREs is that they cannot be softened (reduced stiffness) under an external magnetic field. Considering that there are many engineering applications where fast changes of stiffness in both directions (stiffening and softening) are required, embedding magnetically biased particles in the MRE can provide potential solutions. In this …


Development And Characterization Of Lead & Lead-Free Perovskite Solar Cell Materials, Rubaiya Murshed Aug 2023

Development And Characterization Of Lead & Lead-Free Perovskite Solar Cell Materials, Rubaiya Murshed

UNLV Theses, Dissertations, Professional Papers, and Capstones

In recent years, perovskite photovoltaic technology has offered enormous viability and dimensionality in solar cell research. As a light-harvesting active layer, Perovskite generated remarkable development in device efficiency of 25.7% for the single-junction solar cell, and over 33% for the perovskite/silicon tandem solar cell. Also, perovskite-perovskite tandem solar cell (also called all-perovskite tandem solar cell) shows great potential in device performance and achieved a power conversion efficiency (PCE) of 26.4%. Transitioning photovoltaic technology from the laboratory to commercial products, high PCE, low cost, long lifetime, and low toxicity are some of the critical factors to consider during material selection. Pb-halide …


Magmatic Processes Leading To Compositional Diversity In The Mars Crust, Amanda Marie Ostwald Aug 2023

Magmatic Processes Leading To Compositional Diversity In The Mars Crust, Amanda Marie Ostwald

UNLV Theses, Dissertations, Professional Papers, and Capstones

The ancient Mars crust can yield insights into planet formation and evolution that Earth cannot. Direct investigation of the martian surface is limited to studies on meteorites and rover-obtained analyses. The nakhlites and chassignites, two classes of martian meteorites, are together the largest suite of martian meteorites derived from a single location on the surface. As such, they present a rare opportunity to study the Mars crust in detail using samples bearing a contextual relationship. Rover studies have found a surprising amount of compositional diversity in surface materials, the formation mechanisms of which are not well-constrained. This dissertation leverages meteorites …


Benchmarking And Practical Evaluation Of Machine And Statistical Learning Methods In Credit Scoring: A Method Selection Perspective, Gwen Verbeck Aug 2023

Benchmarking And Practical Evaluation Of Machine And Statistical Learning Methods In Credit Scoring: A Method Selection Perspective, Gwen Verbeck

UNLV Theses, Dissertations, Professional Papers, and Capstones

Predictive models are important tools used in all scientific fields. Machine learning (ML) algorithms and statistical models are widely used for decision-making because of their capability to tackle intricate and unique problems. In domains where data are high-dimensional and contain irrelevant and redundant features, ML algorithms are known to have superior performance over traditional (statistical) learning methods. However, researchers and analysts are often faced with a myriad of techniques to choose from, with no clear consensus on which will perform best for their specific task. Considering resource limitations, exhaustive exploration of all available methods is impractical and often fails to …


Development Of A Metapgs For Accurate Prediction Of Osteoporotic Fracture, Xiangxue Xiao Aug 2023

Development Of A Metapgs For Accurate Prediction Of Osteoporotic Fracture, Xiangxue Xiao

UNLV Theses, Dissertations, Professional Papers, and Capstones

Introduction: Early identification of individuals at high-risk for osteoporotic fractures who may benefit from preventive intervention is essential. However, the predictive accuracy of the currently used fracture risk assessment tool remains suboptimal. The first aim of this research is to construct genome-wide polygenic scores for the femoral neck (PGS_FNBMDidpred) and total body BMD (PGS_TBBMDidpred) and to estimate their potential in identifying individuals with a high risk of osteoporotic fractures. The second aim is to validate the predictive performance of two previously established PGSs (PGS_FNBMDidpred and PGS_TBBMDidpred) in an external cohort …