Optimal Stopping for the Uniform Distribution
Alexander Gnedin
TL;DR
The work studies optimal stopping for i.i.d. uniform draws, first revisiting Moser’s problem and deriving its planar Poisson limit to obtain the asymptotic rule $v(T)=2/T$. It then transfers to the discrete-uniform setting with horizon $n$ and range $N$ in the regime $n/N\to T$, where a Poisson limit yields the limit $u(T)$ and a family of beta strategies with cutoffs $\delta_k$. A key contribution is showing that, via a simple time change, Lindley’s minimum-rank problem emerges with a fixed limit $R_n\to 3.869...$, while the discrete-uniform problem yields explicit two-sided bounds and the infinite-product structure for the cutoff sequence. The results connect three classic stopping problems through the planar Poisson framework and provide explicit asymptotic strategies, including the optimal $b=2$ beta-strategy, together with detailed cutoff recursions and densities. The findings offer a principled bridge between discrete and continuous stopping problems and advance the toolbox for Poisson-based optimal stopping with rank- and value-based losses.
Abstract
Many discrete-time optimal stopping problems are known to have more tractable limit forms based on a planar Poisson process. Using this tool we find a solution to the optimal stopping problem for i.i.d. sequence of $n$ discrete uniform random variables, in the asymptotic regime where $n$ and the range of distribution are of the same order. The optimal stopping rule in the Poisson problem is identified, by means of a time change, with known asymptotic solution to Lindley's problem of minimising the expected rank.
