Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Mena, Ramsés H., Merkatas, Christos, Nicoleris, Theodoros, Rodríguez, Carlos E.
Format: Preprint
Veröffentlicht: 2025
Schlagworte:
Online-Zugang:https://arxiv.org/abs/2512.24414
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866913017697927168
author Mena, Ramsés H.
Merkatas, Christos
Nicoleris, Theodoros
Rodríguez, Carlos E.
author_facet Mena, Ramsés H.
Merkatas, Christos
Nicoleris, Theodoros
Rodríguez, Carlos E.
contents Discrete random probability measures are central to Bayesian inference, particularly as priors for mixture modeling and clustering. A broad and unifying class is that of proper species sampling processes (SSPs), encompassing many Bayesian nonparametric priors. We show that any proper SSP admits an exact two-stage finite-mixture representation built from a latent truncation index and a simple reweighting of the atoms. For each realized truncation index, the representation has finitely many atoms, and averaging over the induced law of that index recovers the original SSP setwise. This yields at least two consequences: (i) an exact two-stage finite construction for arbitrary SSPs, without user-chosen truncation levels; and (ii) posterior inference in SSP mixture models via standard finite-mixture machinery, leading to tractable MCMC algorithms without ad hoc truncations. We explore these consequences by deriving explicit total-variation bounds for the approximation error when the truncation level is fixed, and by studying practical performance in mixture modeling, with emphasis on Dirichlet and geometric SSPs.
format Preprint
id arxiv_https___arxiv_org_abs_2512_24414
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Exact two-stage finite-mixture representations for species sampling processes
Mena, Ramsés H.
Merkatas, Christos
Nicoleris, Theodoros
Rodríguez, Carlos E.
Methodology
Statistics Theory
Computation
Discrete random probability measures are central to Bayesian inference, particularly as priors for mixture modeling and clustering. A broad and unifying class is that of proper species sampling processes (SSPs), encompassing many Bayesian nonparametric priors. We show that any proper SSP admits an exact two-stage finite-mixture representation built from a latent truncation index and a simple reweighting of the atoms. For each realized truncation index, the representation has finitely many atoms, and averaging over the induced law of that index recovers the original SSP setwise. This yields at least two consequences: (i) an exact two-stage finite construction for arbitrary SSPs, without user-chosen truncation levels; and (ii) posterior inference in SSP mixture models via standard finite-mixture machinery, leading to tractable MCMC algorithms without ad hoc truncations. We explore these consequences by deriving explicit total-variation bounds for the approximation error when the truncation level is fixed, and by studying practical performance in mixture modeling, with emphasis on Dirichlet and geometric SSPs.
title Exact two-stage finite-mixture representations for species sampling processes
topic Methodology
Statistics Theory
Computation
url https://arxiv.org/abs/2512.24414