Julian Dörfler, Benito van der Zander, Markus Bläser, Maciej Liskiewicz
{"title":"Probabilistic and Causal Satisfiability: the Impact of Marginalization","authors":"Julian Dörfler, Benito van der Zander, Markus Bläser, Maciej Liskiewicz","doi":"arxiv-2405.07373","DOIUrl":"https://doi.org/arxiv-2405.07373","url":null,"abstract":"The framework of Pearl's Causal Hierarchy (PCH) formalizes three types of\u0000reasoning: observational, interventional, and counterfactual, that reflect the\u0000progressive sophistication of human thought regarding causation. We investigate\u0000the computational complexity aspects of reasoning in this framework focusing\u0000mainly on satisfiability problems expressed in probabilistic and causal\u0000languages across the PCH. That is, given a system of formulas in the standard\u0000probabilistic and causal languages, does there exist a model satisfying the\u0000formulas? The resulting complexity changes depending on the level of the\u0000hierarchy as well as the operators allowed in the formulas (addition,\u0000multiplication, or marginalization). We focus on formulas involving marginalization that are widely used in\u0000probabilistic and causal inference, but whose complexity issues are still\u0000little explored. Our main contribution are the exact computational complexity\u0000results showing that linear languages (allowing addition and marginalization)\u0000yield NP^PP-, PSPACE-, and NEXP-complete satisfiability problems, depending on\u0000the level of the PCH. Moreover, we prove that the problem for the full language\u0000(allowing additionally multiplication) is complete for the class succ$exists$R\u0000for languages on the highest, counterfactual level. Previous work has shown\u0000that the satisfiability problem is complete for succ$exists$R on the lower\u0000levels leaving the counterfactual case open. Finally, we consider constrained\u0000models that are restricted to a small polynomial size. The constraint on the\u0000size reduces the complexity of the interventional and counterfactual languages\u0000to NEXP-complete.","PeriodicalId":501024,"journal":{"name":"arXiv - CS - Computational Complexity","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140935005","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ali Mohammad Lavasani, Yaqiao Li, Mehran Shakerinava
{"title":"Newman's theorem via Carathéodory","authors":"Ali Mohammad Lavasani, Yaqiao Li, Mehran Shakerinava","doi":"arxiv-2406.08500","DOIUrl":"https://doi.org/arxiv-2406.08500","url":null,"abstract":"We give a streamlined short proof of Newman's theorem in communication\u0000complexity by applying the classical and the approximate Carath'eodory's\u0000theorems.","PeriodicalId":501024,"journal":{"name":"arXiv - CS - Computational Complexity","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141518334","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ma Junchi, Chen Weilin, Wang Chen, Lin Defu, Wang Chao
{"title":"Decision algorithms for reversibility of one-dimensional non-linear cellular automata under null boundary conditions","authors":"Ma Junchi, Chen Weilin, Wang Chen, Lin Defu, Wang Chao","doi":"arxiv-2405.03609","DOIUrl":"https://doi.org/arxiv-2405.03609","url":null,"abstract":"The property of reversibility is quite meaningful for the classic theoretical\u0000computer science model, cellular automata. For the reversibility problem for a\u0000CA under null boundary conditions, while linear rules have been studied a lot,\u0000the non-linear rules remain unexplored at present. The paper investigates the\u0000reversibility problem of general one-dimensional CA on a finite field\u0000$mathbb{Z}_p$, and proposes an approach to optimize the Amoroso's infinite CA\u0000surjectivity detection algorithm. This paper proposes algorithms for deciding\u0000the reversibility of one-dimensional CA under null boundary conditions. We\u0000propose a method to decide the strict reversibility of one-dimensional CA under\u0000null boundary conditions. We also provide a bucket chain based algorithm for\u0000calculating the reversibility function of one-dimensional CA under null\u0000boundary conditions. These decision algorithms work for not only linear rules\u0000but also non-linear rules. In addition, it has been confirmed that the\u0000reversibility function always has a period, and its periodicity is related to\u0000the periodicity of the corresponding bucket chain. Some of our experiment\u0000results of reversible CA are presented in the paper, complementing and\u0000validating the theoretical aspects, and thereby further supporting the research\u0000conclusions of this paper.","PeriodicalId":501024,"journal":{"name":"arXiv - CS - Computational Complexity","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140883817","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Leo van Iersel, Mark Jones, Jannik Schestag, Celine Scornavacca, Mathias Weller
{"title":"Maximizing Network Phylogenetic Diversity","authors":"Leo van Iersel, Mark Jones, Jannik Schestag, Celine Scornavacca, Mathias Weller","doi":"arxiv-2405.01091","DOIUrl":"https://doi.org/arxiv-2405.01091","url":null,"abstract":"Network Phylogenetic Diversity (Network-PD) is a measure for the diversity of\u0000a set of species based on a rooted phylogenetic network (with branch lengths\u0000and inheritance probabilities on the reticulation edges) describing the\u0000evolution of those species. We consider the textsc{Max-Network-PD} problem:\u0000given such a network, find~$k$ species with maximum Network-PD score. We show\u0000that this problem is fixed-parameter tractable (FPT) for binary networks, by\u0000describing an optimal algorithm running in $mathcal{O}(2^r log\u0000(k)(n+r))$~time, with~$n$ the total number of species in the network and~$r$\u0000its reticulation number. Furthermore, we show that textsc{Max-Network-PD} is\u0000NP-hard for level-1 networks, proving that, unless P$=$NP, the FPT approach\u0000cannot be extended by using the level as parameter instead of the reticulation\u0000number.","PeriodicalId":501024,"journal":{"name":"arXiv - CS - Computational Complexity","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140826992","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A Smoothed Analysis of the Space Complexity of Computing a Chaotic Sequence","authors":"Naoaki Okada, Shuji Kijima","doi":"arxiv-2405.00327","DOIUrl":"https://doi.org/arxiv-2405.00327","url":null,"abstract":"This work is motivated by a question whether it is possible to calculate a\u0000chaotic sequence efficiently, e.g., is it possible to get the $n$-th bit of a\u0000bit sequence generated by a chaotic map, such as $beta$-expansion, tent map\u0000and logistic map in $mathrm{o}(n)$ time/space? This paper gives an affirmative\u0000answer to the question about the space complexity of a tent map. We show that\u0000the decision problem of whether a given bit sequence is a valid tent code is\u0000solved in $mathrm{O}(log^{2} n)$ space in a sense of the smoothed complexity.","PeriodicalId":501024,"journal":{"name":"arXiv - CS - Computational Complexity","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140827008","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"An Oracle with no $mathrm{UP}$-Complete Sets, but $mathrm{NP}=mathrm{PSPACE}$","authors":"David Dingel, Fabian Egidy, Christian Glaßer","doi":"arxiv-2404.19104","DOIUrl":"https://doi.org/arxiv-2404.19104","url":null,"abstract":"We construct an oracle relative to which $mathrm{NP} = mathrm{PSPACE}$, but\u0000$mathrm{UP}$ has no many-one complete sets. This combines the properties of an\u0000oracle by Hartmanis and Hemachandra [HH88] and one by Ogiwara and Hemachandra\u0000[OH93]. The oracle provides new separations of classical conjectures on optimal proof\u0000systems and complete sets in promise classes. This answers several questions by\u0000Pudl'ak [Pud17], e.g., the implications $mathsf{UP} Longrightarrow\u0000mathsf{CON}^{mathsf{N}}$ and $mathsf{SAT} Longrightarrow mathsf{TFNP}$ are\u0000false relative to our oracle. Moreover, the oracle demonstrates that, in principle, it is possible that\u0000$mathrm{TFNP}$-complete problems exist, while at the same time $mathrm{SAT}$\u0000has no p-optimal proof systems.","PeriodicalId":501024,"journal":{"name":"arXiv - CS - Computational Complexity","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140826973","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Limits of Sequential Local Algorithms on the Random $k$-XORSAT Problem","authors":"Kingsley Yung","doi":"arxiv-2404.17775","DOIUrl":"https://doi.org/arxiv-2404.17775","url":null,"abstract":"The random $k$-XORSAT problem is a random constraint satisfaction problem of\u0000$n$ Boolean variables and $m=rn$ clauses, which a random instance can be\u0000expressed as a $Gmathbb{F}(2)$ linear system of the form $Ax=b$, where $A$ is\u0000a random $m times n$ matrix with $k$ ones per row, and $b$ is a random vector.\u0000It is known that there exist two distinct thresholds $r_{core}(k) < r_{sat}(k)$\u0000such that as $n rightarrow infty$ for $r < r_{sat}(k)$ the random instance\u0000has solutions with high probability, while for $r_{core} < r < r_{sat}(k)$ the\u0000solution space shatters into an exponential number of clusters. Sequential\u0000local algorithms are a natural class of algorithms which assign values to\u0000variables one by one iteratively. In each iteration, the algorithm runs some\u0000heuristics, called local rules, to decide the value assigned, based on the\u0000local neighborhood of the selected variables under the factor graph\u0000representation of the instance. We prove that for any $r > r_{core}(k)$ the sequential local algorithms with\u0000certain local rules fail to solve the random $k$-XORSAT with high probability.\u0000They include (1) the algorithm using the Unit Clause Propagation as local rule\u0000for $k ge 9$, and (2) the algorithms using any local rule that can calculate\u0000the exact marginal probabilities of variables in instances with factor graphs\u0000that are trees, for $kge 13$. The well-known Belief Propagation and Survey\u0000Propagation are included in (2). Meanwhile, the best known linear-time\u0000algorithm succeeds with high probability for $r < r_{core}(k)$. Our results\u0000support the intuition that $r_{core}(k)$ is the sharp threshold for the\u0000existence of a linear-time algorithm for random $k$-XORSAT.","PeriodicalId":501024,"journal":{"name":"arXiv - CS - Computational Complexity","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140826977","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Maximizing Minimum Cycle Bases Intersection","authors":"Dimitri WatelSAMOVAR, ENSIIE, Marc-Antoine WeisserGALaC, Dominique BarthUVSQ, DAVID, Ylène AboulfathUVSQ, DAVID, Thierry MautorUVSQ, DAVID","doi":"arxiv-2404.17223","DOIUrl":"https://doi.org/arxiv-2404.17223","url":null,"abstract":"We address a specific case of the matroid intersection problem: given a set\u0000of graphs sharing the same set of vertices, select a minimum cycle basis for\u0000each graph to maximize the size of their intersection. We provide a\u0000comprehensive complexity analysis of this problem, which finds applications in\u0000chemoinformatics. We establish a complete partition of subcases based on\u0000intrinsic parameters: the number of graphs, the maximum degree of the graphs,\u0000and the size of the longest cycle in the minimum cycle bases. Additionally, we\u0000present results concerning the approximability and parameterized complexity of\u0000the problem.","PeriodicalId":501024,"journal":{"name":"arXiv - CS - Computational Complexity","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140809364","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A Multivariate to Bivariate Reduction for Noncommutative Rank and Related Results","authors":"Vikraman Arvind, Pushkar S Joglekar","doi":"arxiv-2404.16382","DOIUrl":"https://doi.org/arxiv-2404.16382","url":null,"abstract":"We study the noncommutative rank problem, ncRANK, of computing the rank of\u0000matrices with linear entries in $n$ noncommuting variables and the problem of\u0000noncommutative Rational Identity Testing, RIT, which is to decide if a given\u0000rational formula in $n$ noncommuting variables is zero on its domain of\u0000definition. Motivated by the question whether these problems have deterministic\u0000NC algorithms, we revisit their interrelationship from a parallel complexity\u0000point of view. We show the following results: 1. Based on Cohn's embedding theorem cite{Co90,Cohnfir} we show\u0000deterministic NC reductions from multivariate ncRANK to bivariate ncRANK and\u0000from multivariate RIT to bivariate RIT. 2. We obtain a deterministic NC-Turing reduction from bivariate $RIT$ to\u0000bivariate ncRANK, thereby proving that a deterministic NC algorithm for\u0000bivariate ncRANK would imply that both multivariate RIT and multivariate ncRANK\u0000are in deterministic NC.","PeriodicalId":501024,"journal":{"name":"arXiv - CS - Computational Complexity","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140801325","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A Brief Note on a Recent Claim About NP-Hard Problems and BQP","authors":"Michael C. Chavrimootoo","doi":"arxiv-2406.08495","DOIUrl":"https://doi.org/arxiv-2406.08495","url":null,"abstract":"This short note outlines some of the issues in Czerwinski's paper [Cze23]\u0000claiming that NP-hard problems are not in BQP. We outline one major issue and\u0000two minor issues, and conclude that their paper does not establish what they\u0000claim it does.","PeriodicalId":501024,"journal":{"name":"arXiv - CS - Computational Complexity","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141518335","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}