Title: Stochastics is not Statistics! An introduction to random walk models in hydrogeology Language: English
Speaker: Tomás Aquino
Title: Stochastics is not Statistics! An introduction to random walk models in hydrogeology
Department: Geosciences
Type of talk: General
Date: 12th April 2023
Time: 12.00 pm.
Venue: Saminari A
Length: up to 20 minutes
Abstract:
Statistical analysis is a familiar and widespread concept. Especially in the age of Big Data and machine learning, its applicability and usefulness are common knowledge. Stochastic modeling, however, is less well-known. Loosely speaking, statistical methods aim to characterize the variability in a population or system, or to extract information from large data sets. Stochastic methods, on the other hand, generally aim to derive dynamical models for the evolution of a system subject to incomplete information. One of the key concepts behind stochastic approaches is the derivation of deterministic models despite small-scale uncertainty. A paradigm of this idea is Einstein’s original Brownian motion model in terms of a random walk. In hydrogeology, multi-scale heterogeneity from the pore to the field scale in aquifers and other natural systems makes stochastic approaches powerful tools for deriving theoretical and numerical approaches to model large-scale phenomena, such as contaminant fate and transport or nutrient cycles. In this talk, I will give a brief introduction to random walk methods and their application to transport and reaction processes in hydrogeology, with an emphasis on conceptual understanding rather than mathematical rigor. This will lead us to explore the relationships between the apparently-disparate concepts of solute transport and reaction, the central limit theorem and differentiation, and their generalizations in the presence of multi-scale heterogeneity.
Seminars are open to anyone. Punctuality is much appreciated since the seminars start at 12.00 p.m. sharp.
