I am an Assistant Member of Biostatistics in the Public Health Sciences Division,
Fred Hutchinson Cancer Research Center, and an Affiliate Assistant Professor of
Biostatistics at UW. I obtained my PhD degree in Biostatistics from the Johns Hopkins
University in 2009. 

My research interests include functional, longitudinal and multivariate data, hypothesis
testing in complex models, measurement error and latent variable models, and their
applications in public health and biomedical studies. My recent collaborative research
involves projects in the Women's Health Initiative, to investigate environmental and
genetic risk factors for cancer and cardiovascular diseases. In particular, we aim to
improve assessments of diet and physical activity through objective biomarkers and
accelerometers, and study their association with health outcomes. 



Change Point Testing in Logistic Regression Models with Interaction Term (with Youyi Fong and Sallie Permar), UW Biostatistics working papers (2014)

The threshold effect takes place in situations where the relationship between an outcome variable and...



Multilevel sparse functional principal component analysis (with Ciprian Crainiceanu and Wolfgang Jank), Stat (2014)

We consider analysis of sparsely sampled multilevel functional data, where the basic observational unit is...



Hypothesis Testing for an Extended Cox Model with Time-Varying Coefficients (with Ying Qing Chen), Biometrics (2013)

In many randomized clinical trials, the log-rank test has routinely been used to detect a...



Proportional mean residual life model for right-censored length-biased data (with Gary KWUN CHUEN Chan and Ying Qing Chen), Biometrika (2012)

To study disease association with risk factors in epidemiologic studies, cross-sectional sampling is often more...



Multilevel latent class models with Dirichlet mixing distribution (with Karen Bandeen-Roche), Biometrics (2011)

Latent class analysis (LCA) and latent class regression (LCR) are widely used for modeling multivariate...


Unpublished Papers

Testing homogeneity in parametric and semiparametric mixture case-control models (with Gary KWUN CHUEN Chan, Cheng Zheng, and Kung-Yee Liang), Biometrics (submitted) (2014)

Recently, Qin and Liang (Biometrics, 2011) considered a semiparametric mixture case-control model and proposed a...

On Likelihood Ratio Tests When Nuisance Parameters are Present Only Under the Alternative (with Kung-Yee Liang), Electronic Journal of Statistics (submitted) (2013)

In parametric models, when one or more parameters disappear under the null hypothesis, the likelihood...