Decision Making under Costly Sequential Information Acquisition: the Paradigm of Reversible and Irreversible Decisions
Renyuan Xu, Thaleia Zariphopoulou, Luhao Zhang
TL;DR
This paper develops a novel framework for decision making under costly sequential information acquisition with reversible choices between a known product $A$ and an unknown product $B$. The DM learns via two information regimes and can revert a first choice at a cost, yielding a hierarchical, nested optimal stopping problem analyzed through viscosity solutions. The authors establish existence, uniqueness, and regularity results, characterize exploration vs. product-selection regions, and provide comparative insights relative to the standard irreversible model under both Poisson and Gaussian refined signals. The approach unifies sequential decisions, information costs, and evolving information sources, with broad implications for AI adoption, data service choices, healthcare, and finance, and offers a flexible methodological framework for future extensions.
Abstract
Decision making in modern stochastic systems, including e-commerce platforms, financial markets and healthcare systems, has evolved into a multifaceted process that combines information acquisition and adaptive information sources. This paper initiates a study on such integrated settings, where these elements are not only fundamental but, also, interact in a complex and stochastically intertwined manner. We introduce a relatively simple model, which, however, captures the involved novel elements. A decision maker (DM) may choose between an established product $A$ of known value and a new product $B$ whose value is unknown. In parallel, the DM observes signals about the unknown value of product $B$ and can, also, opt to exchange it for product $A$ if $B$ is initially chosen. Mathematically, the model gives rise to sequential optimal stopping problems with distinct informational regimes (before and after buying product $B$), differentiated by the initial, coarser signal and the subsequent, more accurate one. We analyze in detail the underlying problems using predominantly viscosity solution techniques, departing from the existing literature on information acquisition which is based on traditional optimal stopping arguments. More broadly, the modeling approach introduced herein offers a novel framework for developing more complex interactions among decisions, information sources and information costs in stochastic environments, through a sequence of nested obstacle problems.
