Martin Lysy

Department of Statistics and Actuarial Science, University of Waterloo

“Comparison and Assessment of Models for Particle Diffusion in Biological Fluids”

Date: Friday, November 7, 2014

Rapidly progressing particle tracking techniques have revealed that foreign particles in biological fluids exhibit rich and at times unexpected behavior, with important consequences for drug delivery. Yet, there remains a frustrating lack of coherence in the description of these particles' motion. Largely this is due to a reliance on functional statistics (e.g., mean-squared displacement) to perform model selection and assess goodness-of-fit. However, not only are these functional characteristics typically estimated with substantial variability, but they are shared by many stochastic processes -- each making fundamentally different predictions for important quantities of scientific interest.

Here, we conduct a detailed Bayesian analysis of leading candidate models for subdiffusive particle trajectories in human pulmonary mucus. Model selection is achieved by way of intrinsic Bayes factors, which avoid both noninformative priors and "using the data twice". Goodness-of-fit is evaluated via several second-order criteria along with exact model residuals. Our findings suggest that a simple model of fractional Brownian motion describes the data just as well as a first-principles physical model of viscoelastic subdiffusion.

Graduations

Congratulations to our October, 2018 graduates: Jenna Tichon (Ph.D.), Kanika Grover (M.Sc.), Mohammed Kamso (M.Sc.), Inesh Munaweera Arachchilage (M.Sc.), Joynob Siddiqua (M.Sc.), Shamsia Sobhan (M.Sc.).

Important Date

October 3: Fee Payment Deadline Fall Term

Upcoming Seminars

Statistics seminar: Bo Li: “Spatially Varying Autoregressive Models for Prediction of New HIV Diagnoses” — Thursday, September 20 at 2:45 p.m., P230 Duff Roblin.

Statistics seminar: Mohammad Jafari Jozani: “Quantile Regression with Nominated Samples: An example in Osteoporosis Analysis” — Thursday, September 27 at 2:45 a.m., P230 Duff Roblin.

Statistics seminar: Yuliya Martsynyuk — Thursday, October 4 at 2:45 a.m., P230 Duff Roblin.

Statistics seminar: Darja Barr: “Evidence Driven Best Practices for Teaching the Mathematical Sciences” — Thursday, October 11 at 2:45 a.m., P230 Duff Roblin.

Where are they now?

Taraneh Abarin, Ph.D. (2009)

Yanqing Yi, Ph.D. (2008)