Upcoming Events

Columbia Biostatistics Annual Symposium 2025: Transforming Public Health Through Innovation April 7th, 2025, 8:30am - 5:00pm Allan Rosenfield Building, 8th Floor Auditorium   This year’s one-day event will showcase our newly developed statistical innovations and highlight how they advance clinical practices and influence public health policy. We will also celebrate our educational achievements in training the next generation of biostatisticians, emphasizing the importance of effective collaboration and transdisciplinary research. CBAS is designed to engage the broader scientific community in a free exchange of research ideas and implementation for the future of health-related research and learning. Please join us to see how, as a department, we work across the university and beyond to advance biomedical research through methodological innovations.   More information on schedule, talks, and keynote speaker to come both here and on the website event page. If you are not affiliated with Columbia University but are interested in attending, please email Erin Elliott (ee2548@cumc.columbia.edu)

Thursday, April 17th 11:45am - 1:00pm, ARB Hess Commons Ali Shojaie, PhD Professor of Biostatistics & Statistics, Associate Chair of Biostatistics University of Washington Inference on Function-Valued Parameters Using a Restricted Score Test Function-valued parameters that can be defined as the minimizer of a population risk arise naturally in many applications. Examples include the conditional mean function and the density function. Although there is an extensive literature on constructing consistent estimators for function-valued risk minimizers, such estimands can typically only be estimated at a slower-than-parametric rate in nonparametric and semiparametric models, and performing calibrated inference can be challenging. In this talk, we present a general inferential framework for function-valued risk minimizers as a nonparametric extension of the classical score test. We demonstrate that our framework is applicable in a wide variety of problems and describe how the approach can be used for inference on a mean regression function under (i) nonparametric and (ii) partially additive models. Biostatistics Departmental Seminars & Lectures Lectures are in-person only unless marked otherwise. For all Zoom inquiries to attend seminars with a listed virtual option, please send an email to Erin Elliott, Programs Coordinator (ee2548@cumc.columbia.edu). During the Fall and Spring semesters, the Department of Biostatistics holds regular seminars on Thursdays, called the Levin Lecture Series, on a wide variety of topics which are of interest to both students and faculty. Over each semester, there are also often guest lectures outside the regular Thursday Levin Lecture Series, to provide a robust schedule the covers the wide range of topics in Biostatistics. The speakers are invited guests who spend the day of their seminar discussing their research with Biostatistics faculty and students. 

Thursday, April 24th 11:45am - 1:00pm, ARB Hess Commons Amita Manatunga, PhD Donna J. Brogan Professor in Biostatistics Rollins School of Public Health, Emory University Model-free Framework for Evaluating the Reliability of a New Device with Multiple Imperfect Reference Standards A common practice for establishing the reliability of a new computer-aided diagnostic (CAD) device is to evaluate how well its clinical measurements agree with those of a gold standard test. However, in many clinical studies, a gold standard is unavailable, and one needs to aggregate information from multiple imperfect reference standards for evaluation. A key challenge here is the heterogeneity in diagnostic accuracy across different reference standards, which may lead to biased evaluation of a device if improperly accounted for during the aggregation process. We propose an intuitive and easy-to-use statistical framework for evaluation of a device by assessing agreement between its measurements and the weighted sum of measurements from multiple imperfect reference standards, where weights representing relative reliability of each reference standard are determined by a model-free, unsupervised inductive procedure. Specifically, the inductive procedure recursively assigns higher weights to reference standards whose assessments are more consistent with each other and form a majority opinion, while assigning lower weights to those with greater discrepancies. Unlike existing methods, our approach does not require any modeling assumptions or external data to quantify heterogeneous accuracy levels of reference standards. It only requires specifying an appropriate agreement index used for weight assignment and device evaluation. The framework is applied to evaluate a CAD device for kidney obstruction by comparing its diagnostic ratings with those of multiple nuclear medicine physicians. This is joint work with Ying Cui, Qi Yu and Jeong H. Jang. Biostatistics Departmental Seminars & Lectures Lectures are in-person only unless marked otherwise. For all Zoom inquiries to attend seminars with a listed virtual option, please send an email to Erin Elliott, Programs Coordinator (ee2548@cumc.columbia.edu). During the Fall and Spring semesters, the Department of Biostatistics holds regular seminars on Thursdays, called the Levin Lecture Series, on a wide variety of topics which are of interest to both students and faculty. Over each semester, there are also often guest lectures outside the regular Thursday Levin Lecture Series, to provide a robust schedule the covers the wide range of topics in Biostatistics. The speakers are invited guests who spend the day of their seminar discussing their research with Biostatistics faculty and students.