Homepage of

Sixia Chen

Welcome to my homepage! I am currently an assistant professor at the Department of Biostatistics and Epidemiology at University of Oklahoma Health Sciences Center.

CONTACT INFO

Phone: (405) 271-2229 x48628

Office: The University of Oklahoma Health Sciences Center, 801 NE 13th St, Room 325, Oklahoma City, OK 73104

Email: Sixia-Chen@ouhsc.edu

EDUCATION

  • 1997-2000: ChangJun Middle School, Changsha, Hunan, China
  • 2000-2003: ChangJun High School, Changsha, Hunan, China
  • 2003-2007: BA in Mathematics at Fudan University, Shanghai, China
  • 2007-2012: PhD in Statistics at Iowa State University, USA, Advisor: Professor Jae Kwang Kim
  • 2017-2018: Certificate of University of Oklahoma Health Sciences Center (OUHSC) Faculty Leadership Program

EMPLOYMENT HISTORY

  • June. 2018 – Present: Director of Novel Methodologies Unit of Biostatistics, Epidemiology, and Research Design Core of the Oklahoma Shared Clinical and Translational Resources (OSCTR)
  • Sep. 2017 - Present: Biostatistician of Biomedical and Behavioral Methodology Core (BBMC) at University of Oklahoma Health Science Center
  • Aug. 2016 – Present: Statistical consultant of Tribal Epidemiology Center at Southern Plains Tribal Health Board
  • Feb. 2016 – Present: Faculty member of Biostatistics Core for Stephenson Cancer Center at OU
  • June. 2015 – Present: Survey Methodologist at Sooner Survey Center at OU
  • June. 2015 – Present: Assistant Professor, University of Oklahoma, U.S.A.
  • Aug. 2012 – May. 2015: Senior Statistician, Westat
  • Aug. 2008 – July. 2012: Research Assistant, Center of Survey and Statistical Methodology (CSSM), Department of Statistics, Iowa State University
  • May. 2011 – Aug. 2011: Statistical Analyst, Mathematica Policy Research
  • Aug. 2007 – July. 2008: Teaching Assistant, Department of Statistics, Iowa State University

RESEARCH INTERESTS

  • Missing data analysis
  • Survey sampling
  • Empirical likelihood
  • Nonparametric and Semiparametric Methods
  • Causal inference
  • Big data
  • Biostatistics

AWARDS

  • 2013 Graybill Conference Student Travel Award in Corolado State University
  • 2012 SRMS Student Travel Award, Survey Research Methods Section, American Statistical Association
  • 2008 Kempthorne Award in Statistics: Presented annually to recognize the top student in linear models. Iowa State University
  • 2002 First Prize in National High School Mathematics League, China
  • 2000 First Prize in National Middle School Mathematics League, China

GRANTS

Funded

  • A novel cost-efficient oversampling approach for telephone surveys conducted among minority populations. PI: Sixia Chen. University of Oklahoma Health Science Center, Presbyterian Health Foundation seed grant, $38,405, 07/01/2017-06/30/2018
  • Dual Influences of Vaping and Smoking Identities on Young Adult Smokers Who Use electronic Cigarettes. PI: Cheney Marshall, OUHSC PI: Sixia Chen. NIH R03. $24,302, 09/01/2017-08/31/2019
  • Novel sampling and missing data analysis methods for American Indian population. PI: Sixia Chen. Southern Plains Tribal Health Board . $20,000, 12/31/2016-12/31/2018 (annually renewable)

Pending

  • Handling missing data in multi-omics study of dental disease by deep learning based sequential imputation approach. NIH R03. Role: Primary Investigator.
  • Improving the representativeness of Tribal Behavioral Risk Factor Surveillance System through machine learning and propensity score weighting based data integration . NIH R21. Role: Primary Investigator.
  • Clostridium difficile Spore Aerosol Generation, Transport, and Environmental Deposition in the Patient Care Environment . NIH R01. Role: Co-Investigator.
  • Effects of Court-Ordered Tobacco Corrective Statements on Awareness and Attitudes. NIH R21. Role: Co-Investigator.
  • Development of a Pollen Forecasting System Using the Weather Research and Forecasting Model Coupled with Chemistry (WRF-Chem). NIH R03. Role: Co-Investigator

TEACHING

  • Instructor for 5 weeks' short course 'Introduction to small area estimation', Department of Biostatistics and Epidemiology, University of Oklahoma, June. 2019-July.2019
  • Instructor for ‘Nonparametric methods’, Department of Biostatistics and Epidemiology, University of Oklahoma, Aug. 2018-Dec. 2018
  • Instructor for ‘Sampling theory and methods’, Department of Biostatistics and Epidemiology, University of Oklahoma, Jan. 2018-May. 2018
  • Instructor for ‘BSE 5663 Analysis of Frequency Data’, Department of Biostatistics and Epidemiology, University of Oklahoma, Aug. 2017-Dec. 2017
  • Instructor for 6 weeks' short course 'Introduction to missing data analysis', Department of Biostatistics and Epidemiology, University of Oklahoma, May. 2017-June. 2017 (Short Course Web link: http://osctr.ouhsc.edu/intro-missing-data)
  • Instructor (joint with Prof. David Thompson) for ‘Applications of Microcomputers to Data Analysis’, Department of Biostatistics and Epidemiology, University of Oklahoma, Aug. 2016-Dec. 2016
  • Instructor for ‘Sampling theory and methods’, Department of Biostatistics and Epidemiology, University of Oklahoma, Jan. 2016-May. 2016
  • Instructor (joint with Prof. Daniel Zhao) for ‘R Short Course’, Department of Biostatistics and Epidemiology, University of Oklahoma, Oct. 2015-Nov. 2015 (Short Course Web link: http://osctr.ouhsc.edu/r-short-course)
  • Guest instructor for ‘Special topics in research’, The Joint Program in Survey Methodology, University of Maryland, College Park, MD, April, August 2014 and April, August 2013
  • Laboratory Instructor for ‘Survey Sampling Course’, Department of Statistics, Iowa State University, Ames, IA, Jan. 2011-May. 2011
  • Teaching Assistant, Department of Statistics, Iowa State University, Ames, IA, Aug. 2007-Aug.2008

PRACTICAL EXPERIENCE

I have more than 10 year’s practical experience in survey sampling and missing data analysis. I worked on many survey projects such as National Health Nutrition and Examination Survey (NHANES), National Health Interview Survey (NHIS), Campus Climate Survey on Sexual Assault and Sexual Misconduct (CCSSASM), Schools and Staffing Survey (SASS), Programmer for the International Assessment of Adult Competencies (PIAAC), Minnesota Survey on Adult Substance use (MSASU), Oklahoma tobacco stops with me (TSWM), Oklahoma shape your future survey, Cherokee Nation Adult Tobacco Survey and so on. For those surveys, I have done power calculation, sampling, weighting, imputation, nonresponse bias analysis, statistical disclosure control and statistical analysis.

PUBLICATIONS

  • Articles in refereed journals
  1. Varshney, R., Murphy, B., Woolington, S., Ghafoory, S., Chen, S., Robison, T., and Ahamed, J. (2018). Inactivation of platelet-derived TGF-β1 attenuates aortic stenosis progression in a robust murine model . Accepted by Blood advances
  2. Nusrat, S., Syed, T., Nusrat, S., Chen, S., Chen, W. J. and Bielefeldt, K. (2018). Assessment of pharmaceutical company and device manufacturer payments to gastroenterologists and their participation in clinical practice guideline panels . Accepted by JAMA Network
  3. James, M., Elise, S., Chen, S., Bruce, C., Sarah, K., Amira, O. and Damon, V. (2018). The RICO Verdict and Corrective Statements: Catalysts for Policy Change? Accepted by Tobacco Regulatory Science
  4. Vidrine, D., Frank-Pearce, S., Vidrine, J., Tahay, P, Marani, S., Chen, S., Yuan, Y., Cantor, S. and Prokhorov, A. (2018). Efficacy of an automated text messaging cessation intervention for low socioeconomic smokers: A randomized controlled trial. Accepted by JAMA Internal Medicine
  5. Logan, S., Owen, D., Chen, S., Chen, W. J., Ungvari, Z., Farley, J., Csiszar, A., Sharpe, A., Loos, M., Koopmans, B., Richardson, A., and Sonntag, W. E. (2018). Simultaneous assessment of cognitive function, circadian rhythm, and spontaneous activity in aging mice. Geroscience, 40(2), 123-137
  6. S. Chen and D. Zhao. (2018). Quantile regression analysis with complex survey data under informative sampling. Accepted by Journal of Survey Statistics and Methodology (R code available at https://github.com/yandzhao/Quantile-Regression-of-Survey-Data)
  7. K. R. Hansen, R. A. Wild, V. Baker, M. J. Hill, S. Chen, S. Talken, M. P. Diamond, R. S. Legro, C. Coutifaris, R. Alvero, R. D. Robinson, P. Casson, G. M. Christman, N. Santoro, E. Eisenberg, and H. Zhang. (2018). Midluteal Progesterone: A Marker of Treatment Outcomes in Couples With Unexplained Infertility. The Journal of Clinical Endocrinology & Metabolism, 103, 2743–2751
  8. S. Chen and D. Haziza. (2018). Recent methods for dealing with item nonresponse in surveys: a review. Accepted by International Statistical Review (Invited Submission)
  9. S. Chen, D. Haziza, C. Leger and Z. Mashreghi. (2018). Pseudo-population bootstrap methods for imputed survey data. Accepted by Biometrika
  10. S. Chen and D. Haziza. (2018). Jackknife empirical likelihood method for multiply robust estimation with missing data. Computational Statistics and Data Analysis,127, 258-268
  11. A. Comiford, E. Garroutte, C. Barbosa-Leiker, S. Chen and M. McDonell. (2018). Prevalence and indicators of household smoking bans among American Indians. Journal of Community Health, 43(4), 746-755
  12. S. Chen and D. Haziza. (2017). On the nonparametric multiple imputation with multiply robustness. Accepted by Statistica Sinica
  13. Vidrine, D., Frank, S., Savin, M. Waters, A., Li, Y. and Chen, S. (2017). HIV Diagnosis and Disease Progression: A Teachable Moment for Smoking Cessation? Accepted by Nicotine & Tobacco Research
  14. Bashir, M. H., Madhoun, M. F., Kanagala, R., Chen, S., Nusrat, S. and Fazili, J. (2017). Impact of sustained virologic response on short-term clinical outcomes in patients with chronic hepatitis C-related cirrhosis. European Journal of Gastroenterology, 30(3), 296-301
  15. S. Chen and D. Haziza. (2017). Multiply robust imputation procedures for zero-inflated distribution in surveys. Invited submission at METRON, 75, 333–343
  16. N. Ashpole, S. Logan, A. Yabluchanskiy, M. Mitschelen, H. Yan, E. Hodges, Z. Ungvari, A. Csiszar, J. Farley, S. Chen, C. Georgescu, Y. lkeno and W. Sonntag (2017). IGF-1 has sexually dimorphic, pleiotropic, and time-dependent effects on healthspan, pathology, and lifespan. GeroScience, 39(2), 129-145
  17. S. Chen and J. K. Kim. (2017). Semiparametric fractional imputation using empirical likelihood in survey sampling. Statistical Theory and Related Fields, 1, 69-81
  18. X. Chen, J. Stoner, P. S. Montgomery, A. I. Casanegra, F. Silva-Palacios, S. Chen, A. E. Janitz, A W. Gardner. (2017). Prediction of 6-minute walk performance in patients with peripheral artery disease. Journal of Vascular Surgery, 66, 1202-1209.
  19. C. Arriens, S. Chen, D. R. Karp, R. Saxena, K. Sambandam, E. Chakravarty, J. A. James and J. T. Merrill. (2017). Prognostic Significance of Repeat Biopsy in Lupus Nephritis: Histopathologic Worsening and a Short Time between Biopsies is Associated with Significantly Increased risk for End Stage Renal Disease and Death. Clinical Immunology, 185, 3-9
  20. J. Burks, A. Conner, R, Briggs, S. Chen, P. Bonney, C, Glenn, A. Cheema, N. Gross and T. Mapstone. (2017). Risk of Failure in Pediatric Ventriculo-Peritoneal Shunts Placed After Abdominal Surgery. Journal of Neurosurgery: Pediatrics. 19, 571-577.
  21. S. Chen and K. Rust. (2017). An extension of the model-based justification of Kish’s formula for design effects to two and three-stage designs with stratification. Journal of Survey Statistics and Methodology. 5, 111-130.
  22. S. Chen and D. Haziza. (2017). Multiply robust imputation procedures for the treatment of item nonresponse in surveys. Biometrika. 104, 439-453.
  23. B. Purkaple, J. Mold and S. Chen. (2016). Encouraging patient-centered care by including quality-of-life questions on pre-encounter forms. Annals of Family Medicine. 14, 221-226.
  24. S. Chen and G. Kalton. (2015). Geographic oversampling for race/ethnicity using data from the 2010 U.S. population census. Journal of Survey Statistics and Methodology. 3, 543-565.
  25. S. Chen and J. K. Kim. (2014). Two-phase sampling for propensity score estimation in self-selected samples. The Annals of Applied Statistics. 3, 1492-1515.
  26. S. Chen and J. K. Kim. (2014). Population empirical likelihood for nonparametric inference in survey sampling. Statistica Sinica. 24, 335-355.
  27. S. Chen and J. K. Kim. (2014). Semi-parametric inference with a functional-form empirical likelihood. Journal of Korean Statistical Society. 43, 201-214.
  28. P. S. Zhong and S. Chen. (2014). Jackknife empirical likelihood inference with regression imputation and survey data. Journal of Multivariate Analysis. 129, 193-205.
  29. B. Xiong and S. Chen. (2014). Estimating gravity equation models in the presence of sample selection and heteroscedasticity. Applied Economics. 46, 2993-3003.
  30. S. Chen. (2013). A unified theory on empirical likelihood methods for missing data. Statistics and Its Interface. 6, 325-338.
  • Submitted papers:
  1. Martin, M., Conner, A., Burks, J., Smitherman, A., Glenn, C., Baker, C. and Chen, S. (2017). Impact of Intern Work Hour Restrictions on Neurosurgical Resident Education. Submitted to Journal of Neurosurgery
  2. Gunter, T., Chen, S. and Algan, O. (2018). Utlilization of adjuvant radiation therapy for WHO grade II glioma: a National Cancer Database analysis. Submitted to Journal of Neuro-Oncology
  3. Maheshwari, P., Armendi, A., Pham, T. and Chen, S. (2018). Knowledge about the History of Anesthesiology among Anesthesia Professionals. Submitted to Journal of Anesthesia History
  4. Sharma, R., Cooper, C., Chaudhari, K., Chen, S., Scofield, R. and Jeffries, M. (2018). Arthritis in US veterans: A cross-sectional analysis. Submitted to Arthritis Research & Therapy
  5. Clevenger, V., Jeffries, L., Effgen, S., Chen, S., Arnold, S. (2018). School-Based Physical Therapy Services: A Model to Predict the Gap between Ideal and Actual Embedded Services. Revision at Pediatric Physical Therapy
  6. Lora, K., Branscum, P., Chen, S. and Wakefield, D. (2019). Home food environment factors associated with Hispanic preschoolers’ intake of fruits and vegetables. Submitted to Family and Community Health
  7. Perkins, V., Matsuo, K., Mostofizadeh, S., Sims, T., Lea, J., Barnes, D., Chen, S., Carlson, M., Roman, L., Monk, B., Moore, K., and Holman, L. (2019). Combining Whole Pelvic Radiation with Chemotherapy in Stage IVB Cervical Cancer: A Novel Treatment Strategy. Submitted
  8. S. Chen, A. Stubblefield and J. Stoner. (2018). Oversampling minority population in dual-frame telephone survey. Submitted to Journal of Survey Statistics and Methodology
  9. S. Chen, Y. Zhao, Y. Wang. (2019). Sample empirical likelihood estimator for scrambled responses under complex survey design. Submitted to Computational Statistics and Data Analysis
  10. D. Haziza, S. Chen and Y. Gao. (2019). Targeting key survey variables at the nonresponse treatment stage. Submitted to Biometrika
  • Working papers:
  1. S. Chen and J. K. Kim. (2018). Handling nonignorable nonresponse by using semiparametric fractional imputation.
  2. S. Chen and A. Stubblefield. (2018). Sampling rare population for multi-stage designs.
  3. S. Chen and D. Haziza. (2018). A unified pseudo population bootstrap approach for complex survey data.
  4. S. Chen, S. Yang and J. K. Kim. (2019). Nonparametric mass imputation for data integration.
  • Non-refereed papers:
  1. G. Kalton and S. Chen. (2014). Geographic oversampling for race/ethnicity using data from the 2010 U.S. population census. Joint Statistical Meeting Proceeding Paper
  2. J. Li, S. Chen, T. Krenzke and L. Mohadjer. (2014). Replication variance estimation for balanced sampling: an application to the PIAAC study. Joint Statistical Meeting Proceeding Paper
  3. T. Krenzke, K. Hubbell, M. Diallo, A. Gopinath and S. Chen. (2014). Data coarsening and swapping algorithms. Proceedings of the SAS Global Forum.
  4. S. Chen and T. Krenzke. (2013). Inference of domain parameters through an automatic adjustment of degrees of freedom. Proceedings of the 2013 Federal Committee on Statistical Methodology (FCSM) Research Conference.

PRESENTATIONS

  1. S. Chen, S, Yang and J. K. Kim (2019). Nonparametric mass imputation for data integration. Joint statistical meetings (Topic contributed session). Denver, USA.
  2. S. Chen and D. Haziza (2019). A general-purpose multiply robust estimation approach for handling missing values with survey data. International Chinese Statistical Association 2016 Applied Statistics Symposium (invited session). ,Raleigh, NC, U.S.A.
  3. S. Chen and D. Haziza (2018). A unified pseudo population bootstrap approach for complex survey data. Georgia State University department seminar (Invited). Atlanta, GA.
  4. S. Chen and D. Haziza (2018). Pseudo-population bootstrap procedures for multi-stage sampling designs. Joint statistical meetings (Invited session). Vancouver, Canada.
  5. S. Chen and D. Zhao (2018). Quantile regression analysis of survey data under informative sampling. Statistical Society Canada conference (invited speaker). McGill University, Canada.
  6. S. Chen and D. Haziza (2018). Recent development of multiple robust estimation with complex survey data. CRM-CANSSI Workshop for Statistical Inference for complex surveys (Invited speaker). University of Montreal, Canada.
  7. S. Chen and D. Zhao (2018). Quantile regression analysis of survey data under informative sampling. Iowa State University Survey Working Group Seminar (invited speaker). Ames, IA.
  8. S. Chen, D. Haziza, C. Leger and Z. Mashreghi. (2018). Pseudo-population bootstrap methods for imputed survey data. Iowa State University department seminar (invited). Ames, IA.
  9. S. Chen, D. Haziza, C. Leger and Z. Mashreghi. (2018). Pseudo-population bootstrap methods for imputed survey data. University of Oklahoma Health Science Center department seminar. Oklahoma City, OK.
  10. S. Chen and D. Haziza (2017). Multiply Robust Nonparametric Multiple Imputation for the Treatment of Missing Data. Joint statistical meetings (topic contributed session). Baltimore, MD, U.S.A.
  11. S. Chen and J. Kim. (2016). Semi-parametric fractional imputation using empirical likelihood in survey sampling. Joint statistical meetings (topic contributed session). Chicago, IL, U.S.A.
  12. S. Chen and D. Haziza. (2016). Multiply robust imputation procedures for the treatment of item nonresponse in surveys. International Chinese Statistical Association 2016 Applied Statistics Symposium (invited session). Atlanta, GA, U.S.A.
  13. G. Kalton and S. Chen. (2014). Geographic oversampling for race/ethnicity using data from the 2010 U.S. population census. Joint statistical meetings (topic contributed session). Boston, MA, U.S.A.
  14. V. Hsu, S. Chen, T. Krenzke and L. Mohadjer. (2014). Evaluation of sample designs using results from the programme for the international assessment of adult competencies. Joint statistical meetings (topic contributed session). Boston, MA. U.S.A.
  15. J. Li, S. Chen, T. Krenzke and L. Mohadjer. (2014). Replication variance estimation for balanced sampling: an application to the PIAAC study. Joint statistical meetings (topic contributed session). Boston, MA, U.S.A.
  16. S. Chen. (2014). A unified jackknife empirical likelihood based inference with regression imputation, propensity score weighting for missing data. Frontiers of hierarchical modeling in observational studies, complex surveys and big data: a conference honoring professor Malay Ghosh. College Park, MD.
  17. S. Chen and T. Krenzke. (2013). Inference of domain parameter by using dynamic jackknife variance estimator. 2013 Federal Committee on Statistical Methodology (FCSM). Washington DC.
  18. S. Chen. (2013). Jackknife empirical likelihood method for inference with regression imputation. 2013 Graybill Conference (poster session). Fort Collins, CO, USA.
  19. S. Chen. (2012). Jackknife empirical likelihood method for inference with imputed data. Joint statistical meetings (topic contributed session). Sandiego, CA, USA.
  20. J. K. Kim and S. Chen. (2012). Two-phase sampling approach for propensity score estimation in voluntary sampling. Field Symposium in honor of J. N. K. Rao’s 75th birthday, Carleton University, Ottawa, Canada.
  21. S. Chen and J. K. Kim. (2011). Population empirical likelihood for nonparametric inference in survey sampling. International Chinese Statistical Association 2011 Applied Statistics Symposium (Invited session). New York City, USA.
  22. S. Chen and J. K. Kim. (2010). Generalized empirical likelihood method in missing data problem. Joint statistical meetings (topic contributed session). Vancouver, British Columbia, Canada.

PROFESSIONAL SERVICE

  • Associate Editor, Journal of the Korean Statistical Society (JKSS), 1/1/2018-Current

MENTORING EXPERIENCE

  • PhD students:

1. Michael Machiorlatti (PhD in Biostatistics, Co-Advisor with Dr. Sara Vesely)

2. Allshine Chen (PhD in Biostatistics, Co-Advisor with Dr. Daniel Zhao)

3. Xi Chen (PhD in Biostatistics, Committee Member)

4. Justin Dvorak (PhD in Biostatistics, Committee Member)

5. Jonathan Baldwin (PhD in Biostatistics, Committee Member)

  • DrPH students:

1. Sheila Kelley (DrPH, Committee Member)

  • Master students:

1. Alexander Stubblefield (Master in Biostatistics, Advisor)

2. Mark Camardo (Master in Biostatistics, Committee Member)

3. Xi Chen (Master in Biostatistics, Committee Member, Graduated in 2016)

4. Zoona Sarwar (Master in Epidemiology, Committee Member, Graduated in 2017)

5. Ozair Naqvi (Master in Epidemiology, Committee Member, Graduated in 2018)

6. Donna Tyungu (Master in Pediatrics, Committee Member)

7. Midhun Malla (Master in Clinical and Translational Science)

  • MPH students:

1. Olivia Medaris (MPH in Epidemiology, Advisor)

2. Michael Garbe (MPH in Epidemiology, Committee Member, Graduated in 2018)

  • OSCTR Translating Practice into Research Program fellows:

1. Hibah Awwad (Faculty, Pharmaceutical Sciences)

2. Sudarshan Seshadri (Resident, Microbiology & Immunology)

3. Katerine Ntourou (Faculty, Communication Sci & Disorders)

4. Mary Hudson (Faculty, Communication Sci & Disorders)

5. Yacoub AI Sakka (Faculty, Restorative Sciences)

6. Suhair Jambi (Faculty, Restorative Sciences)

7. Sun Young Lee (Assistant Professor, Department of Ophthalmology)

REVIEWERS FOR JOURNALS

  • Australian and New Zealand Journal of Statistics
  • Statistics and Its interface
  • Journal of Official Statistics
  • Journal of the American Statistical Association
  • Journal of Nonparametric Statistics
  • Journal of Korean Statistical Society
  • Journal of Multivariate Analysis
  • Journal of Business & Economic Statistics
  • Journal of the Royal Statistical Society Series C
  • Journal of Causal Inference
  • Journal of Statistical Computation and Simulation
  • Biometrika
  • Statistica Sinica
  • Hacettepe Journal of Mathematics and Statistics
  • Statistics in Biopharmaceutical Research
  • Survey Methodology
  • Annals of Applied Statistics
  • Canadian Journal of Statistics
  • Journal of Survey Statistics and Methodology
  • Environmental and Ecological Statistics
  • Scandinavian Journal of Statistics
  • Computational Statistics and Data Analysis
  • Annals of the Institute of Statistical Mathematics
  • Journal of Statistical Planning and Inference
  • Transactions on Knowledge and Data Engineering
  • Calcutta Statistical Association Bulletin