منابع مشابه
Clustering Problems on Sliding Windows
We explore clustering problems in the streaming sliding window model in both general metric spaces and Euclidean space. We present the first polylogarithmic space O(1)-approximation to the metric kmedian and metric k-means problems in the sliding window model, answering the main open problem posed by Babcock, Datar, Motwani and O’Callaghan [5], which has remained unanswered for over a decade. O...
متن کاملQuerying languages over sliding windows
We study the space complexity of querying languages over data streams in the sliding window model. The algorithm has to answer at any point of time whether the content of the sliding window belongs to a fixed regular language. For regular languages, a trichotomy is shown: For every regular language the optimal space requirement is asymptotically either constant, logarithmic, or linear in the si...
متن کاملAutomata Theory on Sliding Windows
In a recent paper we analyzed the space complexity of streaming algorithms whose goal is to decide membership of a sliding window to a fixed language. For the class of regular languages we proved a space trichotomy theorem: for every regular language the optimal space bound is either constant, logarithmic or linear. In this paper we continue this line of research: We present natural characteriz...
متن کاملEfficient Summing over Sliding Windows
This paper considers the problem of maintaining statistic aggregates over the last W elements of a data stream. First, the problem of counting the number of 1’s in the last W bits of a binary stream is considered. A lower bound of Ω( 1 +logW ) memory bits forW -additive approximations is derived. This is followed by an algorithm whose memory consumption is O( 1 + logW ) bits, indicating that th...
متن کاملSubmodular Maximization over Sliding Windows
In this paper we study the extraction of representative elements in the data stream model in the form of submodular maximization. Different from the previous work on streaming submodular maximization, we are interested only in the recent data, and study the maximization problem over sliding windows. We provide a general reduction from the sliding window model to the standard streaming model, an...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Journal of Computer and System Sciences
سال: 2012
ISSN: 0022-0000
DOI: 10.1016/j.jcss.2011.04.004