Collective phenomena in community ecology

Traditional theoretical ecology describes low-dimensional patterns (few species, few traits...) used as archetypes for intuition. Network models combine many such patterns into more complex systems, but this comes with hard empirical challenges: predictions are sensitive to the whole structure of species interactions, and this structure is difficult to measure precisely and exhaustively.

New approaches, inspired by statistical mechanics, try to make more general predictions on these high-dimensional systems. The underlying assumption is that large systems that have emerged through many …

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Modeling and measuring subjective values

How to connect values in decision theory, instruments in psychometrics, and norms in classical sociology and anthropology?

Many difficulties have emerged from decades of striving to model human behavior and experience on the basis of utility (e.g. wellbeing, preferences, and other notions from behavioral economics and decision theory). That framework assumes that goals and values are a stable or slowly-changing property of individuals, and that the object of theory is to explain shorter time scales: how humans will (or should) …

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Spatial structure and regimes in ecological dynamics

Numerous studies in ecology have considered the effects of spatial structure on various properties of populations, communities and ecosystems. Very few have asked how the interplay between local and spatial processes can lead to well defined regimes with distinct dynamics, or how changing the spatial structure (as might occur due to landscape fragmentation) can switch the system between these regimes.

As it turns out, by focusing on the role of dimensional properties in these systems (e.g. system size or rate …

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