Ph.D., Texas A&M University-College Station, Statistics, 1993.
M.S., National Tsing-Hua University, Applied Mathematics, 1985.
Missing Data, Measurement Error and Nutritional Epidemiology.
I have two primary biostatistics research activities: (1) methodology research on missing data, measurement error models, longitudinal data and survival analysis; (2) application of methods to epidemiological data.
Missing data and measurement error are very practical and interesting problems. Due to certain reasons, such as high cost, some data can only be collected for a small subsample. For example, food frequency questionnaires are commonly used to assess dietary intake for most study participants, while other instruments such as 4DFR may be subsequently administered only to a subsample of participants to reduce costs. Other factors of missing data problem may be due to the design eligibility criteria. The Women's Health Initiative's dietary intervention trial is a standard example. Furthermore, nutrients are often measured with error. Ignorance of the measurement error may sometimes dead to considerable bias to the study results.
Dietary intervention trialshave been strategies for the nutritional prevention of cancer. This leads to a covariate measurement error problem in regression models. A closely related problem arising from the regression analysis of two-stage case-control studies. To this problem, I have developed some parametric, semiparametric and nonparametric methods.
I am also interested in the missing data and measurement error problem in censored failure time data. Some work has been done in this field.
Recently, I have been working on regression analysis when the disease outcome is related to longitudinal data which are observations from a random effects model. This problem is often called joint modeling or two-stage modeling. The primary regression is to relate disease outcome to some latent covariates, while the auxillary data regression is to model covariate data.
I am also interested in the missing data and measurement error problem in censored failure time data.
(Reading, Writing, Speaking)
Chinese, Mandarin: (Fluent, None, None)
English: (Fluent, None, None)
American Statistical Association
Honors and Awards
The H.O. Hartley Award, Department of Statistics, Texas A&M University
2001-2005, Affiliate Associate Professor, University of Washington, School of Public Health and Community Medicine, Biostatistics
1998-2002, Associate Member, Fred Hutchinson Cancer Research Center, Biostatistics, Public Health Sciences
1993-1998, Assistant Member, Fred Hutchinson Cancer Research Center, Biostatistics, Public Health Sciences
1993-2001, Affiliate Assistant Professor, University of Washington, School of Public Health and Community Medicine, Biostatistics
1989-1993, Teaching/Research Assistant, Texas A&M University-College Station, Statistics
1987-1989, Research Assistant, Institute of Statistical Science, Academia Sinica, Taipei, Taiwan
Dietary Weight Loss, Exercise, and Oxidative Stress in Postmenopausal Women: A Randomized Controlled Trial.. Cancer prevention research (Philadelphia, Pa.). 9(11):835-843.. 2016.
Augmented case-only designs for randomized clinical trials with failure time endpoints.. Biometrics. 72(1):30-38.. 2016.
Effects of vitamin D supplementation during weight loss on sex hormones in postmenopausal women.. Menopause (New York, N.Y.). 23(6):645-652.. 2016.
Penalized count data regression with application to hospital stay after pediatric cardiac surgery.. Statistical methods in medical research. 25(6):2685-2703.. 2016.
Robust best linear estimator for Cox regression with instrumental variables in whole cohort and surrogates with additive measurement error in calibration sample.. Biometrical journal. Biometrische Zeitschrift.. 2016.
Effects of Vitamin D3 Supplementation on Lean Mass, Muscle Strength, and Bone Mineral Density During Weight Loss: A Double-Blind Randomized Controlled Trial.. Journal of the American Geriatrics Society.. 2016.
Higher Eating Frequency Does Not Decrease Appetite in Healthy Adults.. The Journal of nutrition.. 2015.
Variable selection for zero-inflated and overdispersed data with application to health care demand in Germany.. Biometrical journal. Biometrische Zeitschrift.. 2015.
An economic evaluation of colorectal cancer screening in primary care practice.. American journal of preventive medicine. 48(6):714-21.. 2015.
Effect of Vitamin D3 supplementation in combination with weight loss on inflammatory biomarkers in postmenopausal women: a randomized controlled trial.. Cancer prevention research (Philadelphia, Pa.). 8(7):628-35.. 2015.
Metabolic responses to a traditional Mexican diet compared with a commonly consumed US diet in women of Mexican descent: a randomized crossover feeding trial.. The American journal of clinical nutrition.. 2015.
Increased breast cancer screening and down-staging in Colombian women: A randomized trial of opportunistic breast-screening.. International journal of cancer. Journal international du cancer.. 2015.
Predicting Adherence of Adults to a 12-Month Exercise Intervention.. Journal of physical activity & health. 11(7):1304-12.. 2014.
Results of nurse navigator follow-up after positive colorectal cancer screening test: a randomized trial.. Journal of the American Board of Family Medicine : JABFM. 27(6):789-95.. 2014.
Cruciferous vegetables have variable effects on biomarkers of systemic inflammation in a randomized controlled trial in healthy young adults.. The Journal of nutrition. 144(11):1850-7.. 2014.
Vitamin D3 supplementation during weight loss: a double-blind randomized controlled trial.. The American journal of clinical nutrition.. 2014.
Time to Screening in the Systems of Support to Increase Colorectal Cancer Screening Trial.. Cancer epidemiology, biomarkers & prevention : a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive Oncology.. 2014.
Aspirin and Serum Estrogens in Postmenopausal Women: a Randomized Controlled Clinical Trial.. Cancer prevention research (Philadelphia, Pa.).. 2014.
Effect of a 12-month Exercise Intervention on Serum Biomarkers of Angiogenesis in Postmenopausal Women: a randomized controlled trial.. Cancer epidemiology, biomarkers & prevention : a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive Oncology.. 2014.
The central role of comorbidity in predicting ambulatory care sensitive hospitalizations.. European journal of public health. 24(1):66-72.. 2014.