Overview
I'm a stochastic modeler-- I build computer-resident mathematical models
for complex systems, and invent and program numerical algorithms for making
inference from the models. Usually this involves predicting things that
haven't been measured (yet). Always it involves managing uncertainty and
making good decisions when some of the information we'd need to be fully
comfortable in our decision-making is unknown.
Originally trained as a mathematician specializing in probability theory and
stochastic processes, I was drawn to statistics by the interplay between
theoretical and applied research- with new applications suggesting what
statistical areas need theoretical development, and advances in theory and
methodology suggesting what applications were becoming practical and so
interesting. Through all of my statistical interests (theoretical, applied,
and methodological) runs the unifying theme of the Likelihood Principle,
a constant aid in the search for sensible methods of inference in complex
statistical problems where commonly-used methods seem unsuitable.
Three specific examples of such areas are:
- Computer modeling, the construction and analysis of fast small Bayesian
statistical emulators for big slow simulation models; - Meta-analysis, of how we can synthesize evidence of different sorts about
a statistical problem; and - Nonparametric Bayesian analysis, for applications in which common
parametric families of distributions seem unsuitable.
Many of the methods in common use in each of these areas are hard or
impossible to justify, and can lead to very odd inferences that seem to
misrepresent the statistical evidence. Many of the newer approaches
abandon the ``iid'' paradigm in order to reflect patterns of regional
variation, and abandon familiar (e.g. Gaussian) distributions in order to
reflect the heavier tails observed in realistic data, and nearly all of
them depend on recent advances in the power of computer hardware and
algorithms, leading to three other areas of interest:
- Spatial Statistics,
- Statistical Extremes, and
- Statistical computation.
I have a special interest in developing statistical methods for application
to problems in Environmental Science, where traditional methods often fail.
Recent examples include developing new and better ways to estimate the
mortality to birds and bats from encounters with wind turbines; the
development of nonexchangeable hierarchical Bayesian models for
synthesizing evidence about the health effects of environmental pollutants;
and the use of high-dimensional Bayesian models to reflect uncertainty in
mechanistic environmental simulation models.
My current research involves modelling and Bayesian inference of dependent
time series and (continuous-time) stochastic processes with jumps (examples
include work loads on networks of digital devices; peak heights in mass
spectrometry experiments; or multiple pollutant levels at spatially and
temporally distributed sites), problems arising in astrophysics (Gamma ray
bursts) and high-energy physics (heavy ion collisions), and the statistical
modelling of risk from, e.g., volcanic eruption.
Current Appointments & Affiliations
Recent Publications
Markov Infinitely-Divisible Stationary Time-Reversible Integer-Valued Processes
Journal Article Sankhya A · November 1, 2024 We prove a complete class theorem that characterizes all stationary time reversible Markov processes whose finite dimensional marginal distributions (of all orders) are infinitely divisible. Aside from two degenerate cases (iid and constant), in both discr ... Full text CiteHard jet substructure in a multistage approach
Journal Article Physical Review C · October 1, 2024 We present predictions and postdictions for a wide variety of hard jet-substructure observables using a multistage model within the jetscape framework. The details of the multistage model and the various parameter choices are described in [Phys. Rev. C 107 ... Full text CiteTopographic Controls on Pyroclastic Density Current Hazard at Aluto Volcano (Ethiopia) Identified Using a Novel Zero-Censored Gaussian Process Emulator
Journal Article Journal of Geophysical Research: Solid Earth · May 1, 2024 Aluto volcano (Central Ethiopia) displays a complex, hybrid topography, combining elements typical of caldera systems (e.g., a central, flat caldera floor) and stratovolcanoes (e.g., relatively high and steep, radial flanks, related to eruptions occurring ... Full text CiteRecent Grants
Ixchel: Building understanding of the physical, cultural and socio-economic drivers of risk for strengthening resilience in the Guatemalan cordillera
ResearchPrincipal Investigator · Awarded by University of Edinburgh · 2021 - 2025Collaborative Research: Capturing salient features in point process models via stochastic process discrepancies
ResearchPrincipal Investigator · Awarded by National Science Foundation · 2020 - 2023Collaborative Research: Using Precursor Information to Update Probabilistic Hazard Maps
ResearchPrincipal Investigator · Awarded by National Science Foundation · 2018 - 2022View All Grants