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arXiv · 2610.40272

posterior-landscape: morphological feature finding in two-dimensional probability densities

Michele Mancarella·Viola De Renzis·Alessandro Agapito
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Abstract

We present posterior-landscape, a Python framework to identify and characterize morphological features in two-dimensional probability densities. The framework combines concepts from topological data analysis, statistical density-ridge estimation, and scale-space image analysis. It extracts localized concentrations, valleys, ridges, and changes of slope; for Bayesian reconstructions, it propagates uncertainty in feature recovery, geometry, and correspondence across posteriors. The framework also connects two-dimensional structures to features in one-dimensional marginals, and quantifies their correlation with other inferred parameters. We validate the method on controlled densities, and demonstrate its use on gravitational-wave population reconstructions, where it provides a systematic way to identify and interpret population features and assess which ones carry information relevant for cosmology. The resulting catalogues also offer a common morphological representation for future comparisons between predictions and population reconstructions.

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Michele Mancarella, Viola De Renzis, Alessandro Agapito. 2026-10-29. posterior-landscape: morphological feature finding in two-dimensional probability densities. https://arxiv.org/abs/2610.40272

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