Digital Commons Network^™

A Practical Guide To Harnessing The Har Volatility Model, Adam Clements, Daniel P. A. Preve

Research Collection School Of Economics

The standard heterogeneous autoregressive (HAR) model is perhaps the most popular benchmark model for forecasting return volatility. It is often estimated using raw realized variance (RV) and ordinary least squares (OLS). However, given the stylized facts of RV and well-known properties of OLS, this combination should be far from ideal. The aim of this paper is to investigate how the predictive accuracy of the HAR model depends on the choice of estimator, transformation, or combination scheme made by the market practitioner. In an out-of-sample study, covering the S&P 500 index and 26 frequently traded NYSE stocks, it is found that …

Influence Of Rapid Covid-19 Vaccine Development On Vaccine Hesitancy, Sonny Rosenthal, Christopher L. Cummings

Research Collection College of Integrative Studies

Introduction: In the race to deploy vaccines to prevent COVID-19, there is a need to understand factors influencing vaccine hesitancy. Secondary risk theory is a useful framework to explain this, accounting for concerns about vaccine efficacy and safety. Methods: During the first week of July, 2020, participants (N = 216) evaluated one of three different hypothetical vaccine scenarios describing an FDA-approved vaccine becoming available “next week,” “in one year,” or “in two years.” Dependent variables were perceived vaccine efficacy, self-efficacy, perceived vaccine risk, and vaccination willingness. Covariates included vaccine conspiracy beliefs, science pessimism, media dependency, and perceived COVID-19 risk. Data …

The Human Connectome Project: A Retrospective, Jennifer Stine Elam, Matthew F. Glasser, Michael P. Harms, Gregory C. Burgess, Sandra W. Curtiss, Michael R. Hodge, Eileen A. Cler, Daniel M. Marcus, Deanna M. Barch, David C. Van Essen, Et Al.

2020-Current year OA Pubs

The Human Connectome Project (HCP) was launched in 2010 as an ambitious effort to accelerate advances in human neuroimaging, particularly for measures of brain connectivity; apply these advances to study a large number of healthy young adults; and freely share the data and tools with the scientific community. NIH awarded grants to two consortia; this retrospective focuses on the "WU-Minn-Ox" HCP consortium centered at Washington University, the University of Minnesota, and University of Oxford. In just over 6 years, the WU-Minn-Ox consortium succeeded in its core objectives by: 1) improving MR scanner hardware, pulse sequence design, and image reconstruction methods, …

Development And Validation Of A Lifestyle Behavior Tool In Overweight And Obese Women Through Qualitative And Quantitative Approaches, Chee Wai Ku, Loo Rachel, Cheryl Lim, Jacinth Jia Xin Tan, Joey Ho, Wee Meng Han, Xiang Wen Ng, Jerry Chan, See Ling Loy

Research Collection School of Social Sciences

There is a paucity of effective intervention tools for overweight/obese women to assess, guide and monitor their eating behavior. This study aimed to develop a lifestyle intervention tool, assess its acceptability and usefulness, and verify its construct validity in overweight/obese women. The 6P tool (Portion, Proportion, Pleasure, Phase, Physicality, Psychology) was developed and 15 women with a body mass index (BMI) ≥ 25 kg/m2 were interviewed to assess its perceived acceptability and usefulness. Subsequently, the revised 6P tool was tested in 46 women with a BMI ≥ 25 kg/m2. The Three-Factor Eating Questionnaire (TFEQ), International Physical Activity Questionnaire-Short (IPAQ), and …

Infodemic: The Effect Of Death-Related Thoughts On News-Sharing, Amy J. Lim, Edison Tan, Tania Lim

Research Collection School of Social Sciences

Research on the sharing of fake news has primarily focused on the manner in which fake news spreads and the literary style of fake news. These studies, however, do not explain how characteristics of fake news could affect people’s inclination toward sharing these news articles. Drawing on the Terror Management Theory, we proposed that fake news is more likely to elicit death-related thoughts than real news. Consequently, to manage the existential anxiety that had been produced, people share the news articles to feel connected to close others as a way of resolving the existential anxiety. Across three experimental studies (total …

Russian Logics And The Culture Of Impossible: Part 1. Recovering Intelligentsia Logics, Ksenia Tatarchenko, Anya Yermakova, Liesbeth De Mol

Research Collection College of Integrative Studies

This article reinterprets algorithmic rationality by looking at the interaction between mathematical logic, mechanized reasoning, and, later, computing in the Russian Imperial and Soviet contexts to offer a history of the algorithm as a mathematical object bridging the inner and outer worlds, a humanistic vision that we, following logician Vladimir Uspensky, call the “culture of the impossible.” We unfold the deep roots of this vision as embodied in scientific intelligentsia. In Part I, we examine continuities between the turn-of-the-twentieth-century discussions of poznaniye—an epistemic orientation towards the process of knowledge acquisition—and the postwar rise of the Soviet school of mathematical logic. …

Deriving Invariant Checkers For Critical Infrastructure Using Axiomatic Design Principles, Cheah Huei Yoong, Venkata Reddy Palleti, Rajib Ranjan Maiti, Arlindo Silva, Christopher M. Poskitt

Research Collection School Of Computing and Information Systems

Cyber-physical systems (CPSs) in critical infrastructure face serious threats of attack, motivating research into a wide variety of defence mechanisms such as those that monitor for violations of invariants, i.e. logical properties over sensor and actuator states that should always be true. Many approaches for identifying invariants attempt to do so automatically, typically using data logs, but these can miss valid system properties if relevant behaviours are not well-represented in the data. Furthermore, as the CPS is already built, resolving any design flaws or weak points identified through this process is costly. In this paper, we propose a systematic …

Perceptions Of The Appropriate Response To Norm Violation In 57 Societies, Kimmo Erikkson, Pontus Strimling, Et Al., Andree Hartanto, Norman P. Li

Research Collection School of Social Sciences

Norm enforcement may be important for resolving conflicts and promoting cooperation. However, little is known about how preferred responses to norm violations vary across cultures and across domains. In a preregistered study of 57 countries (using convenience samples of 22,863 students and non-students), we measured perceptions of the appropriateness of various responses to a violation of a cooperative norm and to atypical social behaviors. Our findings highlight both cultural universals and cultural variation. We find a universal negative relation between appropriateness ratings of norm violations and appropriateness ratings of responses in the form of confrontation, social ostracism and gossip. Moreover, …

Setiya On Consequentialism And Constraints, Ryan Cox, Matthew Hammerton

Research Collection School of Social Sciences

It is widely held that agent-neutral consequentialism is incompatible with deontic constraints. Recently, Kieran Setiya has challenged this orthodoxy by presenting a form of agent-neutral consequentialism that he claims can capture deontic constraints. In this reply, we argue against Setiya's proposal by pointing to features of deontic constraints that his account fails to capture.

The Pandemic As Political Opportunity: Jokowi’S Indonesia In The Time Of Covid-19, Charlotte Setijadi

Research Collection School of Social Sciences

In mid-2021, the Delta strain of the Covid-19 virus caused a second wave of transmissions and deaths in Indonesia at a scale much greater than what was seen in 2020. In this paper, I examine what the Indonesian government’s handling of the Covid crisis in 2021 reveals about the priorities of President Joko Widodo (Jokowi), as well as his political agenda and attitude towards the country’s democracy, as he strives to cement his legacy. I argue that, while devastating, the Covid-19 pandemic has given Jokowi the opportunity to push through long-planned economic and political reforms. Furthermore, I contend that, under …

Ogden Type I To Iii Tibial Tubercle Fractures In Skeletally Immature Patients: Is Routine Anterior Compartment Fasciotomy Of The Leg Indicated?, Corey Brown, Brian A. Kelly, Kirsten Brouillet, Scott J. Luhmann

2020-Current year OA Pubs

PURPOSE: Determine the frequency of compartment syndrome of the leg after displaced, operatively treated modified Ogden I to III tibial tubercle fractures (TTFxs), evaluate the preoperative assessment and use of advanced imaging, and need for prophylactic fasciotomies.

METHODS: Retrospective analysis of operatively treated, displaced modified Ogden I to III TTFxs, at our level 1 paediatric trauma centre between 2007 and 2019. Modified Ogden Type IV and V fracture patterns were excluded. Fracture patterns were determined by plain radiographs.

RESULTS: There were 49 modified Ogden I to III TTFxs in 48 patients. None had signs nor symptoms of vascular compromise, compartment …

Rmix: Learning Risk-Sensitive Policies For Cooperative Reinforcement Learning Agents, Wei Qiu, Xinrun Wang, Runsheng Yu, Xu He, Rundong Wang, Bo An, Svetlana Obraztsova, Zinovi Rabinovich

Research Collection School Of Computing and Information Systems

Current value-based multi-agent reinforcement learning methods optimize individual Q values to guide individuals' behaviours via centralized training with decentralized execution (CTDE). However, such expected, i.e., risk-neutral, Q value is not sufficient even with CTDE due to the randomness of rewards and the uncertainty in environments, which causes the failure of these methods to train coordinating agents in complex environments. To address these issues, we propose RMIX, a novel cooperative MARL method with the Conditional Value at Risk (CVaR) measure over the learned distributions of individuals' Q values. Specifically, we first learn the return distributions of individuals to analytically calculate CVaR …

Development Of A Qualified Clinical Data Registry For Emergency Medicine, Stephen K Epstein, Richard T Griffey, Michelle P Lin, James J Augustine, Pawan Goyal, Arjun K Venkatesh

2020-Current year OA Pubs

The passage of the Medicare Access and CHIP Reauthorization Act (MACRA) in 2015 marked a fundamental transition in physician payment by the Centers for Medicare and Medicaid Services (CMS) from traditional fee-for service to value-based models. MACRA led to the creation of the CMS Quality Payment Program (QPP), which bases the value of physician care in large part on physician quality reporting. The QPP enabled a shift away from legacy CMS-stewarded quality measures that had limited applicability to individual specialties toward specialty-specific quality measures developed and stewarded by physician specialty societies using Qualified Clinical Data Registries (QCDRs). This article describes …

Video Snapshot: Single Image Motion Expansion Via Invertible Motion Embedding, Qianshu Zhu, Chu Han, Guoqiang Han, Tien-Tsin Wong, Shengfeng He

Research Collection School Of Computing and Information Systems

Unlike images, finding the desired video content in a large pool of videos is not easy due to the time cost of loading and watching. Most video streaming and sharing services provide the video preview function for a better browsing experience. In this paper, we aim to generate a video preview from a single image. To this end, we propose two cascaded networks, the motion embedding network and the motion expansion network. The motion embedding network aims to embed the spatio-temporal information into an embedded image, called video snapshot. On the other end, the motion expansion network is proposed to …

Neurolkh: Combining Deep Learning Model With Lin-Kernighan-Helsgaun Heuristic For Solving The Traveling Salesman Problem, Liang Xin, Wen Song, Zhiguang Cao, Jie Zhang

Research Collection School Of Computing and Information Systems

We present NeuroLKH, a novel algorithm that combines deep learning with the strong traditional heuristic Lin-Kernighan-Helsgaun (LKH) for solving Traveling Salesman Problem. Specifically, we train a Sparse Graph Network (SGN) with supervised learning for edge scores and unsupervised learning for node penalties, both of which are critical for improving the performance of LKH. Based on the output of SGN, NeuroLKH creates the edge candidate set and transforms edge distances to guide the searching process of LKH. Extensive experiments firmly demonstrate that, by training one model on a wide range of problem sizes, NeuroLKH significantly outperforms LKH and generalizes well to …

Learning To Iteratively Solve Routing Problems With Dual-Aspect Collaborative Transformer, Yining Ma, Jingwen Li, Zhiguang Cao, Wen Song, Le Zhang, Zhenghua Chen, Jing Tang

Research Collection School Of Computing and Information Systems

Recently, Transformer has become a prevailing deep architecture for solving vehicle routing problems (VRPs). However, it is less effective in learning improvement models for VRP because its positional encoding (PE) method is not suitable in representing VRP solutions. This paper presents a novel Dual-Aspect Collaborative Transformer (DACT) to learn embeddings for the node and positional features separately, instead of fusing them together as done in existing ones, so as to avoid potential noises and incompatible correlations. Moreover, the positional features are embedded through a novel cyclic positional encoding (CPE) method to allow Transformer to effectively capture the circularity and symmetry …

Automated Doubt Identification From Informal Reflections Through Hybrid Sentic Patterns And Machine Learning Approach, Siaw Ling Lo, Kar Way Tan, Eng Lieh Ouh

Research Collection School Of Computing and Information Systems

Do my students understand? The question that lingers in every instructor’s mind after each lesson. With the focus on learner-centered pedagogy, is it feasible to provide timely and relevant guidance to individual learners according to their levels of understanding? One of the options available is to collect reflections from learners after each lesson to extract relevant feedback so that doubts or questions can be addressed in a timely manner. In this paper, we derived a hybrid approach that leverages a novel Doubt Sentic Pattern Detection (SPD) algorithm and a machine learning model to automate the identification of doubts from students’ …

Data Fusion For Trust Evaluation, Zheng Yan, Qinghua Zheng, Laurence T. Yang, Robert H. Deng

Research Collection School Of Computing and Information Systems

Trust evaluation is a process to quantify trust by analyzing the data related to the factors that affect trust. It has been widely applied in many fields to facilitate decision making, system entity collaboration and security establishment. For example, in social networking, trust evaluation helps users make a social decision, reduce the risk of social interactions, and ensure the quality of a social networking environment. In digital communications, trust evaluation can be applied to detect malicious nodes, filter unwanted traffic and improve communication security. In e-commerce and cloud services, trust evaluation helps users selecting an appropriate product or service from …

Robust Bipoly-Matching For Multi-Granular Entities, Ween Jiann Lee, Maksim Tkachenko, Hady W. Lauw

Research Collection School Of Computing and Information Systems

Entity matching across two data sources is a prevalent need in many domains, including e-commerce. Of interest is the scenario where entities have varying granularity, e.g., a coarse product category may match multiple finer categories. Previous work in one-to-many matching generally presumes the `one' necessarily comes from a designated source and the `many' from the other source. In contrast, we propose a novel formulation that allows concurrent one-to-many bidirectional matching in any direction. Beyond flexibility, we also seek matching that is more robust to noisy similarity values arising from diverse entity descriptions, by introducing receptivity and reclusivity notions. In addition …

Functional Signatures: New Definition And Constructions, Qingwen Guo, Qiong Huang, Sha Ma, Meiyan Xiao, Guomin Yang, Willy Susilo

Research Collection School Of Computing and Information Systems

Functional signatures (FS) enable a master authority to delegate its signing privilege to an assistant. Concretely, the master authority uses its secret key sk(F) to issue a signing key sk(f) for a designated function f is an element of F-FS and sends both f and sk(f) to the assistant E, which is then able to compute a signature sigma(f) with respect to pk(F) for a message y in the range of f. In this paper, we modify the syntax of FS slightly to support the application scenario where a certificate of authorization is necessary. Compared with the original FS, our …

Increased Mitochondrial Activity Upon Catsper Channel Activation Is Required For Mouse Sperm Capacitation, Juan J Ferreira, Adriana Cassina, Pilar Irigoyen, Mariana Ford, Santiago Pietroroia, Nikita Peramsetty, Rafael Radi, Celia M Santi, Rossana Sapiro

2020-Current year OA Pubs

To fertilize an oocyte, sperm must undergo several biochemical and functional changes known as capacitation. A key event in capacitation is calcium influx through the cation channel of sperm (CatSper). However, the molecular mechanisms of capacitation downstream of this calcium influx are not completely understood. Capacitation is also associated with an increase in mitochondrial oxygen consumption, and several lines of evidence indicate that regulated calcium entry into mitochondria increases the efficiency of oxidative respiration. Thus, we hypothesized that calcium influx through CatSper during capacitation increases mitochondrial calcium concentration and mitochondrial efficiency and thereby contributes to sperm hyperactivation and fertilization capacity. …

Concise Mercurial Subvector Commitments: Definitions And Constructions, Yannan Li, Willy Susilo, Guomin Yang, Tran Viet Xuan Phuong, Yong Yu, Dongxi Liu

Research Collection School Of Computing and Information Systems

Vector commitment and its variants have attracted a lot of attention recently as they have been exposed to a wide range of applications in blockchain. Two special extensions of vector commitments, namely subvector commitments and mercurial commitments, have been proposed with attractive features that are desirable in many applications. Nevertheless, to the best of our knowledge, a single construction satisfying all those attractive features is still missing. In this work, we analyze those important properties and propose a new primitive called mercurial subvector commitments, which are efficiently updatable, mercurial hiding, position binding, and aggregatable. We formalize the system model and …

Clinical And Microbiological Outcomes Of Ceftazidime-Avibactam Treatment In Adults With Gram-Negative Bacteremia: A Subset Analysis From The Phase 3 Clinical Trial Program, John E Mazuski, Florian Wagenlehner, Antoni Torres, Yehuda Carmeli, Joseph W Chow, Dalia Wajsbrot, Gregory G Stone, Paurus Irani, David Bharucha, Karen Cheng, Margaret Tawadrous

2020-Current year OA Pubs

INTRODUCTION: This exploratory analysis assessed efficacy and safety outcomes in patients with Gram-negative bacteremia treated with ceftazidime-avibactam or comparator across five phase 3, randomized, controlled, multi-center trials in adults with complicated intra-abdominal infection (cIAI), complicated urinary tract infection (cUTI)/pyelonephritis, hospital-acquired pneumonia (HAP), and ventilator-associated pneumonia (VAP).

METHODS: In each trial, RECLAIM and RECLAIM 3 (cIAI; NCT01499290/NCT01726023), REPRISE (cIAI/cUTI; NCT01644643), RECAPTURE (cUTI; NCT01595438/NCT01599806), and REPROVE (HAP/VAP; NCT01808092), patients were randomized 1:1 to intravenous ceftazidime-avibactam (plus metronidazole for those with cIAI) or comparators (carbapenems in > 97% patients) for 5-21 days. Efficacy assessments included clinical and microbiological responses at the test-of-cure visit in …

Microservices Orchestration Vs. Choreography: A Decision Framework, Alan @ Ali Madjelisi Megargel, Christopher M. Poskitt, Shankararaman, Venky

Research Collection School Of Computing and Information Systems

Microservices-based applications consist of loosely coupled, independently deployable services that encapsulate units of functionality. To implement larger application processes, these microservices must communicate and collaborate. Typically, this follows one of two patterns: (1) choreography, in which communication is done via asynchronous message-passing; or (2) orchestration, in which a controller is used to synchronously manage the process flow. Choosing the right pattern requires the resolution of some trade-offs concerning coupling, chattiness, visibility, and design. To address this problem, we propose a decision framework for microservices collaboration patterns that helps solution architects to crystallize their goals, compare the key factors, and then …

Channel Integration Services In Online Healthcare Communities, Anqi Zhao, Qian Tang

Research Collection School Of Computing and Information Systems

In online healthcare communities, channel integration services have become the bridge between online and offline channels, enabling patients to easily migrate across channels. Different from pure online services, online-to-offline (On2Off) and offline-to-online (Off2On) channel integration services involve both channels. This study examines the interrelationships between pure online services and channel integration services. Using a panel dataset composed of data from an online healthcare community, we find that pure online services decrease patients’ demand for On2Off integration services but increase their use of Off2On integration services. Our findings suggest that providing healthcare services online can reduce online patients’ needs to visit …

Vireo @ Trecvid 2021 Ad-Hoc Video Search, Jiaxin Wu, Phuong Anh Nguyen, Chong-Wah Ngo

Research Collection School Of Computing and Information Systems

In this paper, we summarize our submitted runs and results for Ad-hoc Video Search (AVS) task at TRECVid 2020

Ai And The Future Of Work: What We Know Today, Steven M. Miller, Thomas H. Davenport

Research Collection School Of Computing and Information Systems

To contribute to a better understanding of the contemporary realities of AI workplace deployments, the authors recently completed 29 case studies of people doing their everyday work with AI-enabled smart machines. Twenty-three of these examples were from North America, mostly in the US. Six were from Southeast Asia, mostly in Singapore. In this essay, we compare our findings on job and workplace impacts to those reported in the MIT Task Force on the Work of the Future report, as we consider that to be the most comprehensive recent study on this topic.

Solving The Vehicle Routing Problem With Simultaneous Pickup And Delivery And Occasional Drivers By Simulated Annealing, Vincent F. Yu, Grace Aloina, Panca Jodiawan, Aldy Gunawan, Tsung-Chi Huang

Research Collection School Of Computing and Information Systems

This research studies the vehicle routing problem with simultaneous pickup and delivery with an occasional driver (VRPSPDOD). VRPSPDOD is a new variant of the vehicle routing problems with simultaneous pickup and delivery (VRPSPD). Different from VRPSPD, in VRPSPDOD, occasional drivers are employed to work with regular vehicles to service customers’ pickup and delivery requests in order to minimize the total cost. We formulate a mixed integer linear programming model for VRPSPD and propose a heuristic algorithm based on simulated annealing (SA) to solve the problem. The results of comprehensive numerical experiments show that the proposed SA performs well in terms …

Towards Non-Intrusive Camera-Based Heart Rate Variability Estimation In The Car Under Naturalistic Condition, Shu Liu, Kevin Koch, Zimu Zhou, Martin Maritsch, Xiaoxi He, Elgar Fleisch, Felix Wortmann

Research Collection School Of Computing and Information Systems

Driver status monitoring systems are a vital component of smart cars in the future, especially in the era when an increasing amount of time is spent in the vehicle. The heart rate (HR) is one of the most important physiological signals of driver status. To infer HR of drivers, the mainstream of existing research focused on capturing subtle heartbeat-induced vibration of the torso or leveraged photoplethysmography (PPG) that detects cardiac cycle-related blood volume changes in the microvascular. However, existing approaches rely on dedicated sensors that are expensive and cumbersome to be integrated or are vulnerable to ambient noise. Moreover, their …

Verification Assisted Gas Reduction For Smart Contracts, Bo Gao, Siyuan Shen, Ling Shi, Jiaying Li, Jun Sun, Lei Bu

Research Collection School Of Computing and Information Systems

Smart contracts are computerized transaction protocols built on top of blockchain networks. Users are charged with fees, a.k.a. gas in Ethereum, when they create, deploy or execute smart contracts. Since smart contracts may contain vulnerabilities which may result in huge financial loss, developers and smart contract compilers often insert codes for security checks. The trouble is that those codes consume gas every time they are executed. Many of the inserted codes are however redundant. In this work, we present sOptimize, a tool that optimizes smart contract gas consumption automatically without compromising functionality or security. sOptimize works on smart contract bytecode, …