This paper centers around a simple yet crucial question for everyday users: How should one choose their delegated validators within proof-of-stake (PoS) protocols, particularly in the context of Ethereum 2.0? This has been a long-overlooked gap, as existing studies have primarily focused on inter-committee (validator set) behaviors and activities, while neglecting the dynamic formation of committees, especially for individual stakeholders seeking reliable validators. Our study bridges this gap by diving into the delegation process (normal users delegate their small-value tokens to delegatees who later act as validators) before entering an actual consensus phase. We propose a Bayesian model to quantify normal users' trust in delegatees, which we further incorporate into a game-theoretical model to simulate users' reactions against a set of critical factors identified through extensive research (including 10+ staking service provider as well as 30+ PoS blockchains). Our results reveal that users tend to choose their delegatees and utilize their tokens by carefully weighing the delegation cost, the behaviors of other users, and the reputation of delegatees, ultimately reaching a Nash equilibrium. Unfortunately, the collective trend significantly increases the likelihood of token concentration on a small number of delegatees.

翻译：本文围绕普通用户面临的一个简单但关键的问题展开：在权益证明（PoS）协议中，特别是在以太坊2.0的背景下，用户应如何选择其委托的验证者？这是一个长期被忽视的研究空白，因为现有研究主要关注委员会间（验证者集）的行为与活动，而忽略了委员会形成的动态过程，尤其是对于寻求可靠验证者的个体利益相关者而言。我们的研究通过深入探讨进入实际共识阶段之前的委托过程（普通用户将其小额代币委托给后来充当验证者的受委托人）来弥补这一空白。我们提出一个贝叶斯模型来量化普通用户对受委托人的信任，并将其进一步融入博弈论模型，以模拟用户对通过广泛研究（涵盖10多家质押服务提供商及30多个PoS区块链）识别出的关键因素集的反应。结果表明，用户倾向于通过仔细权衡委托成本、其他用户的行为及受委托人的声誉来选择受委托人并运用其代币，最终达到纳什均衡。不幸的是，这种集体趋势显著增加了代币集中到少数受委托人手中的可能性。