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Archivio digitale delle tesi discusse presso l’Università di Pisa

Tesi etd-09082021-152407


Tipo di tesi
Tesi di laurea magistrale
Autore
CIMORELLI, MATTIA FRANCESCO
URN
etd-09082021-152407
Titolo
Random Forests and Applications
Dipartimento
MATEMATICA
Corso di studi
MATEMATICA
Relatori
relatore Dott. Trevisan, Dario
Parole chiave
  • Clustering
  • Spanning forest
  • Loop erased random walk
Data inizio appello
24/09/2021
Consultabilità
Completa
Riassunto
Given a weighted and finite graph, an efficient way to sample spanning treesis due to Wilson, who in the 1990s introduced his famous algorithm based onloop-erased random walks. Recently, L. Avena et al. general-ized Wilson’s algorithm to spanning forests with results on the distribution ofthe roots sampled by the algorithm, showing in particular that such set is adeterminantal point process.In this thesis, we first recall the results above and then focus on the case of adiscreted-dimensional torus, so that the associated Markov process is a simplerandom walk. We provide some original results on an asymptotic description ofthe number of roots and Wilson’s algorithm total running time, that we showto be faster than the cover time for a random walk, if d≥2, as predicted byWilson himself.We then report on some known applications of random forests, including therandom generation of rectangular mazes. We explore how well this algorithmdetects a minimum spanning tree Finally we suggest forest-based method for clustering.
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