{"title":"选择k个最优的平均复杂度","authors":"A. Yao, F. Yao","doi":"10.1109/SFCS.1978.29","DOIUrl":null,"url":null,"abstract":"Let Vk (n) be the minimum average number of pairwise comparisons needed to find the k-th largest of n numbers (k≥2), assuming that all n! orderings are equally likely. D. W. Matula proved that, for some absolute constant c, Vk(n)- n ≤ ck log log n as n → ∞. In the present paper, we show that there exists an absolute constant c′ ≫ 0 such that Vk(n) - n ≥ c′k log log n as n → ∞, proving a conjecture by Matula.","PeriodicalId":346837,"journal":{"name":"19th Annual Symposium on Foundations of Computer Science (sfcs 1978)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0000,"publicationDate":"1978-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"7","resultStr":"{\"title\":\"On the average-case complexity of selecting k-th best\",\"authors\":\"A. Yao, F. Yao\",\"doi\":\"10.1109/SFCS.1978.29\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Let Vk (n) be the minimum average number of pairwise comparisons needed to find the k-th largest of n numbers (k≥2), assuming that all n! orderings are equally likely. D. W. Matula proved that, for some absolute constant c, Vk(n)- n ≤ ck log log n as n → ∞. In the present paper, we show that there exists an absolute constant c′ ≫ 0 such that Vk(n) - n ≥ c′k log log n as n → ∞, proving a conjecture by Matula.\",\"PeriodicalId\":346837,\"journal\":{\"name\":\"19th Annual Symposium on Foundations of Computer Science (sfcs 1978)\",\"volume\":\"3 1\",\"pages\":\"0\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"1978-10-16\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"7\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"19th Annual Symposium on Foundations of Computer Science (sfcs 1978)\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.1109/SFCS.1978.29\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"19th Annual Symposium on Foundations of Computer Science (sfcs 1978)","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1109/SFCS.1978.29","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 7
摘要
让Vk (n)成为pairwise最低平均当家》《k-th comparisons需要努力去发现n的最大数字(k≥2),assuming那所有n !订单是一样的。D . W . Matula proved that c为一些绝对康斯坦,Vk (n) - n≤美国ck对数log n n→∞。《现在,这篇文章我们秀那绝对有exists an康斯坦c′≫0如此那Vk (n)美国c - n≥对数log k′n n→∞,证实a conjecture Matula偏。
On the average-case complexity of selecting k-th best
Let Vk (n) be the minimum average number of pairwise comparisons needed to find the k-th largest of n numbers (k≥2), assuming that all n! orderings are equally likely. D. W. Matula proved that, for some absolute constant c, Vk(n)- n ≤ ck log log n as n → ∞. In the present paper, we show that there exists an absolute constant c′ ≫ 0 such that Vk(n) - n ≥ c′k log log n as n → ∞, proving a conjecture by Matula.