Profile likelihood analysis for a stochastic model of diffusion in heterogeneous media

Add to your list(s) Download to your calendar using vCal

• Matthew Simpson (Queensland University of Technology)
• Tuesday 12 September 2023, 11:15-12:00
• Seminar Room 1, Newton Institute.

If you have a question about this talk, please contact nobody.

MMVW03 - Measures and Representations of Interactions

We compute profile likelihoods for a stochastic model of diffusive transport motivated by experimental observations of heat conduction in layered skin tissues. This process is modelled as a random walk in a layered one-dimensional material, where each layer has a distinct particle hopping rate. Particles are released at some location, and the duration of time taken for each particle to reach an absorbing boundary is recorded. Motivated by our experimental data, we aim to explore whether these data can be used to identify the hopping rates in each layer. To achieve this we compute various profile likelihoods using two methods: first, an exact likelihood is evaluated using a computationally expensive Markov chain approach; and, second, we form an approximate likelihood by assuming the distribution of exit times is given by a Gamma distribution whose first two moments match the moments from the continuum limit description of the stochastic model. Using the exact and approximate likelihoods, we construct various profile likelihoods for a range of problems. In cases where parameter values are not identifiable, we make progress by re-interpreting those data with a reduced model with a smaller number of layers.

This talk is part of the Isaac Newton Institute Seminar Series series.

This talk is included in these lists:

• All CMS events
• Featured lists
• INI info aggregator
• Isaac Newton Institute Seminar Series
• School of Physical Sciences
• Seminar Room 1, Newton Institute
• bld31

Note that ex-directory lists are not shown.