{"title":"Optimal Online Bookmaking for Binary Games","authors":"Alankrita Bhatt;Or Ordentlich;Oron Sabag","doi":"10.1109/TIT.2026.3694366","DOIUrl":"https://doi.org/10.1109/TIT.2026.3694366","url":null,"abstract":"In online betting, the bookmaker can update the payoffs it offers on a particular event many times before the event takes place, and the updated payoffs may depend on the bets accumulated thus far. We study the problem of bookmaking with the goal of maximizing the return in the worst-case, with respect to the gamblers’ behavior and the event’s outcome. We formalize this problem as the <italic>Optimal Online Bookmaking game</i>, and provide the exact solution for the binary case. To this end, we develop the optimal bookmaking strategy, which relies on a new technique called bi-balancing trees, that assures that the house loss is the same for all <italic>decisive</i> betting sequences, where the gambler bets all its money on a single outcome in each round.","PeriodicalId":13494,"journal":{"name":"IEEE Transactions on Information Theory","volume":"72 7","pages":"4491-4507"},"PeriodicalIF":2.6,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148509503","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Andreas Theocharous;Lampros Gavalakis;Ioannis Kontoyiannis
{"title":"Pragmatic Lossless Compression: Fundamental Limits and Universality","authors":"Andreas Theocharous;Lampros Gavalakis;Ioannis Kontoyiannis","doi":"10.1109/TIT.2026.3691268","DOIUrl":"https://doi.org/10.1109/TIT.2026.3691268","url":null,"abstract":"The problem of variable-rate lossless data compression is considered, for codes with and without prefix constraints. Sharp bounds are derived for the best achievable compression rate of memoryless sources, when the excess-rate probability is required to be exponentially small in the blocklength. Accurate nonasymptotic expansions with explicit constants are obtained for the optimal rate, using tools from large deviations and Gaussian approximation. When the source distribution is unknown, a universal achievability result is obtained with an explicit “price for universality” term. This is based on a fine combinatorial estimate on the number of sequences with small empirical entropy, which might be of independent interest. Examples are shown indicating that, in the small excess-rate-probability regime, the approximation to the fundamental limit of the compression rate suggested by these bounds is significantly more accurate than the approximations provided by either normal approximation or error exponents. The new bounds reinforce the crucial operational conclusion that, in applications where the blocklength is relatively short and where stringent guarantees are required on the excess-rate probability, the best achievable rate is no longer close to the entropy. Rather, it is an appropriate, more <italic>pragmatic</i> rate, determined via the inverse error exponent function and the blocklength.","PeriodicalId":13494,"journal":{"name":"IEEE Transactions on Information Theory","volume":"72 7","pages":"4587-4601"},"PeriodicalIF":2.6,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148512043","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Minimax Optimal Sample Complexity for Iterated CVaR Reinforcement Learning With a Generative Model","authors":"Zilong Deng;Alvaro Velasquez;Shaofeng Zou","doi":"10.1109/TIT.2026.3692816","DOIUrl":"https://doi.org/10.1109/TIT.2026.3692816","url":null,"abstract":"Standard Reinforcement Learning (RL) algorithms are typically designed to maximize the expected accumulative reward, which may be inadequate in scenarios where risk sensitivity is critical. In this work, the problem of risk-sensitive RL with Iterated Conditional Value at Risk is studied, where the objective is to optimize outcomes under a specified risk level <inline-formula> <tex-math>$tau $ </tex-math></inline-formula> at each step. This work provides the first minimax optimal sample complexity analysis for this problem with a generative model. Specifically, the sample complexity is firstly characterized as a function of the number of states <inline-formula> <tex-math>$S$ </tex-math></inline-formula>, actions <inline-formula> <tex-math>$A$ </tex-math></inline-formula>, and effective horizon <inline-formula> <tex-math>$(1-gamma)^{-1}$ </tex-math></inline-formula> (resp. horizon <inline-formula> <tex-math>$H$ </tex-math></inline-formula> in the finite-horizon setting), and is further shown to be minimax optimal via a novel minimax lower bound analysis when the risk level <inline-formula> <tex-math>$0lt tau leq 1$ </tex-math></inline-formula> is treated as a constant or the risk level is above a threshold of <inline-formula> <tex-math>$gamma $ </tex-math></inline-formula> (resp. <inline-formula> <tex-math>$1-1/H$ </tex-math></inline-formula> in the finite horizon setting). For the case when the risk level is small, the limiting case of <inline-formula> <tex-math>$tau rightarrow 0$ </tex-math></inline-formula>, termed worst-path RL, is then studied, and the minimax optimal sample complexity is also theoretically characterized.","PeriodicalId":13494,"journal":{"name":"IEEE Transactions on Information Theory","volume":"72 7","pages":"5077-5103"},"PeriodicalIF":2.6,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148512146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Doubly Minimized Petz and Sandwiched Rényi Mutual Information: Operational Interpretation From Binary Quantum State Discrimination","authors":"Laura Burri","doi":"10.1109/TIT.2026.3695315","DOIUrl":"https://doi.org/10.1109/TIT.2026.3695315","url":null,"abstract":"The doubly minimized Petz Rényi mutual information of order <inline-formula> <tex-math>$alpha $ </tex-math></inline-formula> is defined as the minimum of the Petz divergence of order <inline-formula> <tex-math>$alpha $ </tex-math></inline-formula> of a given bipartite quantum state relative to all product states. The doubly minimized sandwiched Rényi mutual information is defined analogously, with the Petz divergence replaced by the sandwiched divergence. In this work, we study certain binary quantum state discrimination problems related to correlation detection. We show that the corresponding direct exponent is determined by the doubly minimized Petz Rényi mutual information of order <inline-formula> <tex-math>$alpha in (1/2,1)$ </tex-math></inline-formula>, and that the strong converse exponent is determined by the doubly minimized sandwiched Rényi mutual information of order <inline-formula> <tex-math>$alpha in (1,infty)$ </tex-math></inline-formula>. This provides an operational interpretation of these types of Rényi mutual information and generalizes previous results for classical probability distributions to the quantum setting. For completeness, we also study the corresponding moderate deviation regime both below and above the threshold, and determine the Stein exponent and the second-order asymptotics.","PeriodicalId":13494,"journal":{"name":"IEEE Transactions on Information Theory","volume":"72 7","pages":"4958-4979"},"PeriodicalIF":2.6,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=11527399","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148512262","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nianqi Tang;Yunghsiang S. Han;Chao Chen;Danyang Pei
{"title":"Generalized Inverse Discrete Fourier Transform With Application to Goppa Codes","authors":"Nianqi Tang;Yunghsiang S. Han;Chao Chen;Danyang Pei","doi":"10.1109/TIT.2026.3693655","DOIUrl":"https://doi.org/10.1109/TIT.2026.3693655","url":null,"abstract":"This paper introduces the concept of the generalized inverse discrete Fourier transform over a finite field and studies its application to the decoding of codes. It also proposes an efficient algorithm for computing the generalized inverse discrete Fourier transform, called the fast generalized inverse discrete Fourier transform. Based on this fast transform, the paper shows that, for any <inline-formula> <tex-math>$(n, k)$ </tex-math></inline-formula> generalized Reed–Solomon code, if the underlying field contains an additive or multiplicative subgroup of order <inline-formula> <tex-math>$2^{mu } geq n - k$ </tex-math></inline-formula> and <inline-formula> <tex-math>$n$ </tex-math></inline-formula> is proportional to the field size, then there exists a decoding algorithm with complexity <inline-formula> <tex-math>$Obigl (nlog (n - k) + (n - k)log ^{2}(n - k)bigr)$ </tex-math></inline-formula>. The paper further discusses the additive fast generalized inverse discrete Fourier transform over binary extension fields, which leads to a fast decoding algorithm for binary Goppa codes with complexity <inline-formula> <tex-math>$Obigl (nlog r + rlog ^{2} rbigr)$ </tex-math></inline-formula>, where <inline-formula> <tex-math>$n$ </tex-math></inline-formula> is the code length and <inline-formula> <tex-math>$r$ </tex-math></inline-formula> is the degree of the Goppa polynomial. This achieves the best known decoding complexity for binary Goppa codes to date. A complexity comparison shows that the proposed algorithm reduces the number of field operations by 88% compared to traditional methods when decoding the Goppa code with parameters <inline-formula> <tex-math>$n = 8192$ </tex-math></inline-formula> and <inline-formula> <tex-math>$r = 128$ </tex-math></inline-formula>, which is used in the McEliece cryptosystem as a candidate scheme for post-quantum cryptography.","PeriodicalId":13494,"journal":{"name":"IEEE Transactions on Information Theory","volume":"72 7","pages":"4719-4738"},"PeriodicalIF":2.6,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148507542","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Achievable Rates for the Relay Channel With Orthogonal Receiver Components","authors":"Abbas El Gamal;Amin Gohari;Chandra Nair","doi":"10.1109/TIT.2026.3693057","DOIUrl":"https://doi.org/10.1109/TIT.2026.3693057","url":null,"abstract":"This paper studies lower bounds on the capacity of the relay channel with orthogonal receiver components. We show that the lower bound in Theorem 7 by Cover and El Gamal, which uses a combined decode-forward and compress-forward strategy, is equal to the lower bound of Chong, Motani, and Garg, and is always greater than or equal to the recent lower bound of Mondelli, Hassani, and Urbanke. We provide a simplified expression for the lower bound, interpreting one of its auxiliary random variables as representing the randomized time-sharing strategy. Next, we compute the simplified lower bound for the Gaussian relay channel with orthogonal receiver components and compare it to the existing upper bounds on the capacity. In this case, randomized time-sharing takes the form of <italic>randomized power control</i>. We also study the combined decode-forward and compress-forward lower bound for product-form BSC-BEC channels. Finally, we disprove a conjecture by Ahlswede and Han on the capacity of the subclass of relay channels with orthogonal receiver components and i.i.d. output.","PeriodicalId":13494,"journal":{"name":"IEEE Transactions on Information Theory","volume":"72 7","pages":"4508-4521"},"PeriodicalIF":2.6,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148509504","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Covert Entanglement Generation and Secrecy","authors":"Ohad Kimelfeld;Boulat A. Bash;Uzi Pereg","doi":"10.1109/TIT.2026.3689208","DOIUrl":"https://doi.org/10.1109/TIT.2026.3689208","url":null,"abstract":"We determine the covert capacity for entanglement generation over a noisy quantum channel. While secrecy guarantees that the transmitted information remains inaccessible to an adversary, covert communication ensures that the transmission itself remains undetectable. The entanglement dimension follows a square root law (SRL) in the covert setting, i.e., <inline-formula> <tex-math>$O(sqrt {n})$ </tex-math></inline-formula> Einstein-Podolsky-Rosen (EPR) pairs can be distributed covertly and reliably over <inline-formula> <tex-math>$n$ </tex-math></inline-formula> channel uses. We begin with covert communication of classical information under a secrecy constraint. We then leverage this result to construct a coding scheme for covert entanglement generation. Single-letter expressions are derived for the covert key-assisted and unassisted secrecy capacities, as well as for the covert entanglement-generation capacity.","PeriodicalId":13494,"journal":{"name":"IEEE Transactions on Information Theory","volume":"72 7","pages":"4936-4957"},"PeriodicalIF":2.6,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=11501969","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148511178","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Structured Codes for Distributed Matrix Multiplication","authors":"Derya Malak","doi":"10.1109/TIT.2026.3692427","DOIUrl":"https://doi.org/10.1109/TIT.2026.3692427","url":null,"abstract":"Our work addresses the well-known open problem of distributed computing of bilinear functions of two correlated sources <bold>A</b> and <bold>B</b>. In a setting with two nodes, with the first node having access to <bold>A</b> and the second to <bold>B</b>, we establish bounds on the optimal sum rate that allows a receiver to compute an important class of non-linear functions, and in particular bilinear functions, including dot products <inline-formula> <tex-math>$langle {mathbf { A}},{mathbf { B}}rangle $ </tex-math></inline-formula>, and general matrix products <inline-formula> <tex-math>${mathbf { A}}^{intercal }{mathbf { B}}$ </tex-math></inline-formula> over finite fields. The bounds are tight for large field sizes, for which case we can derive the exact fundamental performance limits for all problem dimensions and a large class of sources. Our achievability scheme involves the design of non-linear transformations of <bold>A</b> and <bold>B</b>, carefully calibrated to work synergistically with the structured linear encoding scheme by Körner and Marton. The subsequent converses derived here, calibrate the Han-Kobayashi approach and the strong converse of Ahlswede-Gács-Körner to yield relatively tight converses on the sum rate. We exhibit unbounded compression gains over Slepian-Wolf coding, depending on the source correlations. In the end, this work characterizes the fundamental limits of distributed computing for a crucial class of functions, while succinctly capturing the inherent computation structures and source correlations.","PeriodicalId":13494,"journal":{"name":"IEEE Transactions on Information Theory","volume":"72 7","pages":"5160-5182"},"PeriodicalIF":2.6,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148511369","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Nonasymptotic Oblivious Relaying and Variable-Length Noisy Lossy Source Coding","authors":"Yanxiao Liu;Sepehr Heidari Advary;Cheuk Ting Li","doi":"10.1109/TIT.2026.3690044","DOIUrl":"https://doi.org/10.1109/TIT.2026.3690044","url":null,"abstract":"The information bottleneck channel (or the oblivious relay channel) concerns a channel coding setting where the decoder does not directly observe the channel output. Rather, the channel output is relayed to the decoder by an oblivious relay (which does not know the codebook) via a rate-limited link. The capacity is known to be given by the information bottleneck. We study finite-blocklength achievability results of the channel, where the relay communicates to the decoder via fixed-length or variable-length codes. These two cases give rise to two different second-order versions of the information bottleneck. Our proofs utilize the nonasymptotic noisy lossy source coding results by Kostina and Verdú, the strong functional representation lemma, and the Poisson matching lemma. Moreover, we also give a novel nonasymptotic variable-length noisy lossy source coding result.","PeriodicalId":13494,"journal":{"name":"IEEE Transactions on Information Theory","volume":"72 7","pages":"4555-4564"},"PeriodicalIF":2.6,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148512040","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Four Classes of LCD Codes From (*)-(L, P)-Twisted Generalized Reed–Solomon Codes","authors":"Zhonghao Liang;Qunying Liao","doi":"10.1109/TIT.2026.3691789","DOIUrl":"https://doi.org/10.1109/TIT.2026.3691789","url":null,"abstract":"It is well known that maximum distance separable (in short, MDS) codes and linear complementary dual (in short, LCD) codes are very important in coding theory and practice. In 2023, Yue et al. constructed three classes of LCD MDS codes via a class of TGRS codes with one twists, i.e., <inline-formula> <tex-math>$(*)$ </tex-math></inline-formula>-TGRS codes. Recently, Wu et al. also constructed several classes of LCD MDS codes via a class of TGRS codes with two twists. In this paper, we unify their constructions by defining the <inline-formula> <tex-math>$(*)$ </tex-math></inline-formula>-<inline-formula> <tex-math>$(mathcal {L},mathcal {P})$ </tex-math></inline-formula>- twisted generalized Reed-Solomon (in short, <inline-formula> <tex-math>$(*)$ </tex-math></inline-formula>-<inline-formula> <tex-math>$(mathcal {L},mathcal {P})$ </tex-math></inline-formula>-TGRS) code, give the parity-check matrix of <inline-formula> <tex-math>$(*)$ </tex-math></inline-formula>-<inline-formula> <tex-math>$(mathcal {L},mathcal {P})$ </tex-math></inline-formula>-TGRS codes, and then construct four classes of LCD codes. Finally, some corresponding examples are given.","PeriodicalId":13494,"journal":{"name":"IEEE Transactions on Information Theory","volume":"72 7","pages":"4788-4801"},"PeriodicalIF":2.6,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148512045","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}