Why Biological Systems Suddenly Change State: An Intuitive Guide to Freidlin–Wentzell Theory

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  Stochasticity is ubiquitous in biology and neuroscience, manifesting in various forms, including ion channel noise, synaptic variability, gene regulatory fluctuations, noisy population dynamics, and more. Many biological systems spend long periods in a stable “state” and only rarely transition to another state due to noise. For instance, a neuron typically remains inactive but may occasionally trigger a spontaneous spike. Similarly, a gene can switch from the OFF state to the ON state due to rare bursts of transcription factors. Cells can also transition out of metabolic or epigenetic states, populations might shift between different ecological equilibria, and a viral infection can fluctuate between phases of control and uncontrollability. Freidlin–Wentzell theory provides a mathematically rigorous framework to study these phenomena when noise is small but nonzero . It tells you, firstly, h ow likely rare transitions are,    secondly,   h ow fast they occ...
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Statistics: the basic tool of scientific research

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Complexity is an ubiquitous condition. We all make decisions of varying importance every day, so one may find strange that decision making involves rather sophisticated mechanisms. However, studies have shown that most people are much poorer at decision making than they think. The understanding of the decision making processes has been the aim of scientific research for many years. 


Decision making rules act not only at a macro-level, whose results we can observe  as economic aggregates, but take a major role also at the micro-level in terms of interactions among neuronal populations. 
In both cases the comprehension of the phenomena relies on robust computational approach. In this sense, statistics offers the tools for modelling and understanding  economic (i.e., social) behaviors and neuronal activities. 

This space is addressed to general and specific topics of statistics, economics, neuroscience, neuroeconomics. Theoretical and computational issues, as well as news, recensions of papers and books, will be promoted. Suggestions and contributions from the readers will be appreciated, since by sharing opinions, facts or ideas may improve the research.

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