A5026844442- Financial Risk and Volatility Modeling
- Forecasting Techniques and Applications
- Statistical Methods and Inference
- HIV/AIDS Research and Interventions
- Pneumocystis jirovecii pneumonia detection and treatment
- Image and Object Detection Techniques
- Hepatitis B Virus Studies
- Industrial Vision Systems and Defect Detection
- Hepatitis C virus research
- Financial Distress and Bankruptcy Prediction
- HIV-related health complications and treatments
- Bayesian Modeling and Causal Inference
- HIV, Drug Use, Sexual Risk
- Metabolomics and Mass Spectrometry Studies
- Credit Risk and Financial Regulations
- Spectroscopy and Chemometric Analyses
- Attachment and Relationship Dynamics
- Forest Biomass Utilization and Management
- HIV/AIDS drug development and treatment
- Sex work and related issues
- Handwritten Text Recognition Techniques
- Monoclonal and Polyclonal Antibodies Research
- Sports Analytics and Performance
- Eating Disorders and Behaviors
- COVID-19 epidemiological studies
University of British Columbia
2018-2025
AIDS Vancouver
2019-2021
Temple University
1978
Handwriting of Chinese has long been an important skill in East Asia. However, automatic generation handwritten characters poses a great challenge due to the large number characters. Various machine learning techniques have used recognize characters, but few works studied character problem, especially with unpaired training data. In this work, we formulate as problem that learns mapping from existing printed font personalized style. We further propose DenseNet CycleGAN generate Our method is...
While general object detection has seen tremendous progress, localization of elliptical objects received little attention in the literature. Our motivating application is knots sawn lumber images, which an important problem since number and types are visual characteristics that adversely affect quality lumber. We demonstrate how models can be tailored to shape thereby improve on purpose detectors; more generally, defects common industrial production, such as enclosed air bubbles when casting...
Abstract Background Hepatitis B (HBV) and Human Immunodeficiency Virus (HIV) share common risk factors for exposure. Co-infected patients have an increased liver-related mortality may accelerated HIV progression. The epidemiology demographic characteristics of HIV-HBV co-infection in Canada remain poorly defined. We compared the clinical associated with advanced hepatic fibrosis between co-infected patients. Methods A retrospective cohort analysis was conducted using data from Canadian...
In this paper, we propose two bootstrap procedures, namely parametric and block bootstrap, to approximate the finite sample distribution of change-point estimators for piecewise stationary time series. The procedures are then used develop a generalized likelihood ratio scan method (GLRSM) multiple inference in series, which estimates number locations change-points provides confidence interval each change-point. computational complexity using GLRSM detection is as low $O(n(\log n)^{3})$...
Abstract Vine pair-copula constructions exist for a mix of continuous and ordinal variables. In some steps, this can involve estimating bivariate copula pair mixed continuous-ordinal To assess the adequacy fits such pair, diagnostic visualization methods based on normal score plots conditional Q–Q are proposed. The former uses latent variable variable. applied to data generated from existing probability models models, Kullback-Leibler divergence is used whether simple parametric families...
To inform vaccination policy and programmatic strategies to increase COVID-19 vaccine uptake, an understanding of the factors associated with willingness vaccinate is needed.
The clinical and demographic characteristics that predict antiretroviral efficacy among patients co-infected with HIV hepatitis B virus (HBV) remain poorly defined. We evaluated virological suppression rebound in a cohort of HIV-HBV initiated on therapy.A retrospective analysis was performed Canadian Observation Cohort Collaboration data. Cox proportional hazards models were used to determine the factors associated time rebound.HBV status available for 2,419 participants. A total 8% HBV...
In this paper we develop a generalized likelihood ratio scan method (GLRSM) for multiple change-points inference in piecewise stationary time series, which estimates the number and positions of provides confidence interval each change-point. The computational complexity using GLRSM detection is as low $O(n(\log n)^3)$ series length $n$. Consistency estimated numbers established. Extensive simulation studies are provided to demonstrate effectiveness proposed methodology under different scenarios.
<h3>Background</h3> Awareness, availability, and public funding of pre-exposure prophylaxis (PrEP) has increased substantially since it was approved by Health Canada in 2016 but policies guidelines vary province. Given the dynamic nature PrEP policy promotion, we sought to determine awareness use among gay, bisexual, other men who have sex with (gbMSM) Vancouver, Toronto, Montreal. <h3>Methods</h3> Beginning 02/2017, sexually-active gbMSM ≥16 years living or Montreal were recruited into a...
<h3>Background</h3> Previous research shows that low self-esteem may negatively affect self-efficacy, increase substance use, and underlie some patterns of risky sexual behaviour. This suggests hinder the prevention HIV other sexually transmitted infections (STI). Therefore, we explored factors related to among gay bisexual men (gbMSM), including associations with risk <h3>Methods</h3> Between 2012–2015, used respondent-driven sampling recruit sexually-active HIV-positive HIV-negative gbMSM,...
Vine pair-copula constructions exist for a mix of continuous and ordinal variables. In some steps, this can involve estimating bivariate copula pair mixed continuous-ordinal To assess the adequacy fits such pair, diagnostic visualization methods based on normal score plots conditional Q-Q are proposed. The former utilizes latent variable variable. Using Kullback-Leibler divergence, existing probability models assessed fit with simple parametric families. effectiveness proposed is illustrated...
To assess the impact of physicians' patient base composition on all-cause mortality among people living with HIV (PLHIV) who initiated highly active antiretroviral therapy (HAART) in British Columbia (BC), Canada.Observational cohort study from 1 January 2000 to 31 December 2013.BC Centre for Excellence HIV/AIDS' (BC-CfE) Drug Treatment Program, where HAART is available at no cost.PLHIV aged ≥ 19 BC Observational Medical Evaluation and Research (HOMER) Study.All-cause as determined through...
<h3>Background</h3> In 2017, we launched a syphilis awareness campaign ("Syphistory") targeted towards gay, bisexual, and other men who have sex with (gbMSM). Using data from study of gbMSM in Vancouver, describe participants reported seeing Syphistory whether it reached at higher risk syphilis. <h3>Methods</h3> Participants aged ≥16 years having another man the previous six months were recruited through respondent-driven sampling. We analyzed collected September 17, 2017 to August 31, 2018....
<h3>Background</h3> We characterized event-level relationship patterns of gay and bisexual men (gbMSM)'s long- short-term with the goal improving intimacy, well-being, control sexually transmitted infections. <h3>Methods</h3> Between 2012–2015, sexually-active gbMSM, aged >16, were recruited in Metro Vancouver using respondent-driven sampling. Participants completed computer-assisted self-interviews at six-month intervals for up to 12 visits. At each visit, participants described their...
While general object detection has seen tremendous progress, localization of elliptical objects received little attention in the literature. Our motivating application is knots sawn timber images, which an important problem since number and types are visual characteristics that adversely affect quality timber. We demonstrate how models can be tailored to shape thereby improve on purpose detectors; more generally, defects common industrial production, such as enclosed air bubbles when casting...
A copula-based approach is used to estimate the dependence among three lumber strength properties: modulus of elasticity ( MOE ), rupture MOR and ultimate tensile UTS ). are destructive measurements so they cannot be obtained simultaneously for specimens. The modeling possible under an appropriate experimental design with i) a shoulder group rupture, ii) tension, iii) other groups proof loaded in either or tension mode survivors tested failure that was not initially tested. With fitted...
Understanding the dependence relationship of credit spreads corporate bonds is important for risk management. Vine copula models with tail are used to analyze a spread dataset Chinese bonds, understand among different sectors and perform conditional inferences. It shown how effect affects transfer, or distributions given one variable extreme. also provide more accurate cross prediction results compared linear regressions. These inference techniques statistical contribution analysis bond...
In statistics, time-to-event analysis methods traditionally focus on the estimation of hazards. recent years, machine learning have been proposed to directly predict event times. We propose a method based vine copula models make point and interval predictions for right-censored response variable given mixed discrete-continuous explanatory variables. Extensive experiments simulated real datasets show that our approach provides decent approximation other including Cox proportional hazards...