Proceedings of IEEE 9th Annual Conference on Structure in Complexity Theory最新文献_第2页

The complexity of learning with queries 通过查询学习的复杂性

Proceedings of IEEE 9th Annual Conference on Structure in Complexity Theory Pub Date : 1994-06-28 DOI: 10.1109/SCT.1994.315791

Ricard Gavaldà

引用次数: 11

Predicate classes and promise classes 谓词类和承诺类

Proceedings of IEEE 9th Annual Conference on Structure in Complexity Theory Pub Date : 1994-06-28 DOI: 10.1109/SCT.1994.315800

Bernd Borchert

引用次数: 10

Weakly hard problems 弱困难问题

Proceedings of IEEE 9th Annual Conference on Structure in Complexity Theory Pub Date : 1994-06-28 DOI: 10.1109/SCT.1994.315808

J. H. Lutz

{"title":"Weakly hard problems","authors":"J. H. Lutz","doi":"10.1109/SCT.1994.315808","DOIUrl":"https://doi.org/10.1109/SCT.1994.315808","url":null,"abstract":"A weak completeness phenomenon is investigated in the complexity class E=DTIME(2/sup linear/). According to standard terminology, a language H is /spl lessub msup P/-hard for E if the set P/sub m/(H), consisting of all languages A/spl lessub msup P/H, contains the entire class E. A language C is /spl lessub msup P/-complete for E if it is /spl lessub msup P/-hard for E and is also an element of E. Generalizing this, a language H is weakly /spl lessub msup P/-hard for E if the set P/sub m/(H) does not have measure 0 in E. A language C is weakly /spl lessub msup P/-complete for E if it is weakly /spl lessub msup P/-hard for E and is also an element of E. The main result of this paper is the construction of a language that is weakly /spl lessub msup P/-complete, but not /spl lessub msup P/-complete, for E. The existence of such languages implies that previously known strong lower bounds on the complexity of weakly /spl lessub msup P/-hard problems for E are indeed more general than the corresponding bounds for /spl lessub msup P/-hard problems for E. The proof of this result introduces a new diagonalization method, called martingale diagonalization. Using this method, one simultaneously develops an infinite family of polynomial time computable martingales (betting strategies) and a corresponding family of languages that defeat these martingales (i.e. prevent them from winning too much money), while also pursuing another agenda. Martingale diagonalization may be useful for a variety of applications.<<ETX>>","PeriodicalId":386782,"journal":{"name":"Proceedings of IEEE 9th Annual Conference on Structure in Complexity Theory","volume":"95 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128590517","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}

引用次数: 45

Relative to a random oracle, NP is not small 相对于随机预言，NP并不小

Proceedings of IEEE 9th Annual Conference on Structure in Complexity Theory Pub Date : 1994-06-28 DOI: 10.1109/SCT.1994.315807

Steven M. Kautz, Peter Bro Miltersen

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引用次数: 27

Complexity classes defined via k-valued functions 通过k值函数定义的复杂度类

Proceedings of IEEE 9th Annual Conference on Structure in Complexity Theory Pub Date : 1994-06-28 DOI: 10.1109/SCT.1994.315801

U. Hertrampf

引用次数: 35

Random debaters and the hardness of approximating stochastic functions 随机辩手和近似随机函数的硬度

Proceedings of IEEE 9th Annual Conference on Structure in Complexity Theory Pub Date : 1994-06-28 DOI: 10.1109/SCT.1994.315796

A. Condon, J. Feigenbaum, C. Lund, P. Shor

引用次数: 74

Downward separation fails catastrophically for limited nondeterminism classes 向下分离对于有限的非确定性类来说是灾难性的失败

Proceedings of IEEE 9th Annual Conference on Structure in Complexity Theory Pub Date : 1994-06-28 DOI: 10.1109/SCT.1994.315810

R. Beigel, J. Goldsmith

{"title":"Downward separation fails catastrophically for limited nondeterminism classes","authors":"R. Beigel, J. Goldsmith","doi":"10.1109/SCT.1994.315810","DOIUrl":"https://doi.org/10.1109/SCT.1994.315810","url":null,"abstract":"The /spl beta/ hierarchy consists of sets /spl betasub k/=NP[log/sup k/ n]/spl sube/NP. Unlike collapses in the polynomial hierarchy and the Boolean hierarchy, collapses in the /spl beta/ hierarchy do not seem to translate up, nor does closure under complement seem to cause the hierarchy to collapse. For any consistent set of collapses and separations of levels of the hierarchy that respects P=/spl betasub 1spl subespl betasub 2spl sube/.../spl sube/NP, we can construct an oracle relative to which those collapses and separations hold, yet any (or all) of the /spl betasub k/'s are closed under complement. We give a few relatively tame examples: first, for any k/spl ges/1, we construct an oracle relative to which P=/spl betasub kspl nespl betasub k+1spl nespl betasub k+2spl ne/..., and then another oracle relative to which P=/spl betasub kspl nespl betasub k+1/=PSPACE. We also construct an oracle relative to which /spl betasub 2k/=/spl betasub 2k+1spl nespl betasub 2k+2/ for all k. These results hold for more general nondeterminism hierarchies within NP, although they are in sharp contrast to the upward collapse results for Buss and Goldsmith's (1993) nondeterminism hierarchy in P.<<ETX>>","PeriodicalId":386782,"journal":{"name":"Proceedings of IEEE 9th Annual Conference on Structure in Complexity Theory","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133112739","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}

引用次数: 20

Complexity theory and genetics 复杂性理论与遗传学

Proceedings of IEEE 9th Annual Conference on Structure in Complexity Theory Pub Date : 1994-06-28 DOI: 10.1109/SCT.1994.315787

P. Pudlák

引用次数: 18

Time, hardware, and uniformity 时间，硬件和一致性

Proceedings of IEEE 9th Annual Conference on Structure in Complexity Theory Pub Date : 1994-06-28 DOI: 10.1109/SCT.1994.315806

D. M. Barrington, N. Immerman

引用次数: 30

Unambiguous polynomial hierarchies and exponential size 明确的多项式层次和指数大小

Proceedings of IEEE 9th Annual Conference on Structure in Complexity Theory Pub Date : 1994-06-28 DOI: 10.1109/SCT.1994.315812

Klaus-Jörn Lange, P. Rossmanith

引用次数: 14