Frank Yoon
PhD Candidate, Department of Statistics
The Wharton School, University of Pennsylvania
400 Jon M. Huntsman Hall, 3730 Walnut Street
Philadelphia, PA 19104
fby at wharton dot upenn dot edu
Research
Current Methodological Project
I am working with Paul Rosenbaum on matching problems. Our current idea is that the propensity score can help a researcher determine the optimal sizes of matched sets in a 1-to-many matching problem. A proposed methodology would be helpful in the situation where there are relatively few study subjects exposed to a treatment compared to a much larger pool of potential comparison subjects. When the costs to obtain information are high, the researcher would like to use just as many subjects as she needs to, without sacrificing reduction in covariate bias and efficiency of the estimator.
Note that the Wikipedia article for the propensity score needs improvement! Help us write :)
Current Clinical Research
I am working with Phyllis Gimotty and Rachel Hammond of the Center for Clinical Epidemiology & Biostatistics/Dept of Biostatistics & Epidemiology on the effectiveness of sentinel lymph node biopsy in the treatment of melanoma. It is believed that cancerous cells from a melanoma begin to metastasize through the sentinel lymph node; removal of this node (or set of nodes) could possibly prevent the spread of the cancer to other parts of the body, and could provide a better alternative to elective regional lymph node dissection which has side effects. We are using the SEER Registry of the National Cancer Institute as our source of observational data.
Grants
I am a Trainee under the Cancer Biostatistics Training Grant of the National Cancer Institute, for which Phyllis Gimotty is the Principal Investigator. This grant supports all my current clinical research as well as my dissertation work with Paul Rosenbaum.
Past Projects
Covariance Adjustment on the Propensity Score in Observational Studies
Subclassification on the Propensity Score in Complex Surveys
Matched Set Sizes Based on the Propensity Score
Past Clinical Research
"An Investigation Into Differential Diagnosis of Pulp and Periapical Pain: A PennEndo Database Study." Journal of Endodontics. May 2007 33:5.