Avoiding Overfitting in Variable-Order Markov Models: a Cross-Validation Approach

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Secchini, Valeria, Garcia-Bernardo, Javier, Janský, Petr
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866912202853711872
author Secchini, Valeria
Garcia-Bernardo, Javier
Janský, Petr
author_facet Secchini, Valeria
Garcia-Bernardo, Javier
Janský, Petr
contents Higher$\text{-}$order Markov chain models are widely used to represent agent transitions in dynamic systems, such as passengers in transport networks. They capture transitions in complex systems by considering not only the current state but also the path of previously visited states. For example, the likelihood of train passengers traveling from Paris (current state) to Rome could increase significantly if their journey originated in Italy (prior state). Although this approach provides a more faithful representation of the system than first$\text{-}$order models, we find that commonly used methods$-$relying on Kullback$\text{-}$Leibler divergence$-$frequently overfit the data, mistaking fluctuations for higher$\text{-}$order dependencies and undermining forecasts and resource allocation. Here, we introduce DIVOP (Detection of Informative Variable$\text{-}$Order Paths), an algorithm that employs cross$\text{-}$validation to robustly distinguish meaningful higher$\text{-}$order dependencies from noise. In both synthetic and real$\text{-}$world datasets, DIVOP outperforms two state$\text{-}$of$\text{-}$the$\text{-}$art algorithms by achieving higher precision, recall, and sparser representations of the underlying dynamics. When applied to global corporate ownership data, DIVOP reveals that tax havens appear in 82$\%$ of all significant higher$\text{-}$order dependencies, underscoring their outsized influence in corporate networks. By mitigating overfitting, DIVOP enables more reliable multi$\text{-}$step predictions and decision$\text{-}$making, paving the way toward deeper insights into the hidden structures that drive modern interconnected systems.
format Preprint
id arxiv_https___arxiv_org_abs_2501_14476
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Avoiding Overfitting in Variable-Order Markov Models: a Cross-Validation Approach
Secchini, Valeria
Garcia-Bernardo, Javier
Janský, Petr
Physics and Society
Social and Information Networks
General Economics
Economics
Higher$\text{-}$order Markov chain models are widely used to represent agent transitions in dynamic systems, such as passengers in transport networks. They capture transitions in complex systems by considering not only the current state but also the path of previously visited states. For example, the likelihood of train passengers traveling from Paris (current state) to Rome could increase significantly if their journey originated in Italy (prior state). Although this approach provides a more faithful representation of the system than first$\text{-}$order models, we find that commonly used methods$-$relying on Kullback$\text{-}$Leibler divergence$-$frequently overfit the data, mistaking fluctuations for higher$\text{-}$order dependencies and undermining forecasts and resource allocation. Here, we introduce DIVOP (Detection of Informative Variable$\text{-}$Order Paths), an algorithm that employs cross$\text{-}$validation to robustly distinguish meaningful higher$\text{-}$order dependencies from noise. In both synthetic and real$\text{-}$world datasets, DIVOP outperforms two state$\text{-}$of$\text{-}$the$\text{-}$art algorithms by achieving higher precision, recall, and sparser representations of the underlying dynamics. When applied to global corporate ownership data, DIVOP reveals that tax havens appear in 82$\%$ of all significant higher$\text{-}$order dependencies, underscoring their outsized influence in corporate networks. By mitigating overfitting, DIVOP enables more reliable multi$\text{-}$step predictions and decision$\text{-}$making, paving the way toward deeper insights into the hidden structures that drive modern interconnected systems.
title Avoiding Overfitting in Variable-Order Markov Models: a Cross-Validation Approach
topic Physics and Society
Social and Information Networks
General Economics
Economics
url https://arxiv.org/abs/2501.14476