| Records |
| Author |
Chierichetti, Flavio; Lattanzi, Silvio; Mari, Federico; Panconesi, Alessandro |
| Title |
On Placing Skips Optimally in Expectation |
Type |
Conference Article |
| Year |
2008 |
Publication |
Web Search and Web Data Mining (WSDM 2008) |
Abbreviated Journal |
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| Volume |
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Issue |
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Pages |
15-24 |
| Keywords |
Information Retrieval |
| Abstract |
We study the problem of optimal skip placement in an inverted list. Assuming the query distribution to be known in advance, we formally prove that an optimal skip placement can be computed quite efficiently. Our best algorithm runs in time O(n log n), n being the length of the list. The placement is optimal in the sense that it minimizes the expected time to process a query. Our theoretical results are matched by experiments with a real corpus, showing that substantial savings can be obtained with respect to the tra- ditional skip placement strategy, that of placing consecutive skips, each spanning sqrt(n) many locations. |
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Thesis |
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| Publisher |
Acm |
Place of Publication |
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Editor  |
Najork, M.; Broder, A.Z.; Chakrabarti, S. |
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Summary Language |
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Original Title |
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Series Issue |
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Edition |
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Expedition |
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Conference |
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| Notes |
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Approved |
yes |
| Call Number |
Sapienza @ mari @ ChiLatMar08 |
Serial |
94 |
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| Author |
Mari, Federico; Melatti, Igor; Salvo, Ivano; Tronci, Enrico |
| Title |
Undecidability of Quantized State Feedback Control for Discrete Time Linear Hybrid Systems |
Type |
Book Chapter |
| Year |
2012 |
Publication |
Theoretical Aspects of Computing – ICTAC 2012 |
Abbreviated Journal |
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| Volume |
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Issue |
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Pages |
243-258 |
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| Abstract |
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Thesis |
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| Publisher |
Springer Berlin Heidelberg |
Place of Publication |
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Editor |
Roychoudhury, A.; D'Souza, M. |
| Language |
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Summary Language |
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Original Title |
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Series Title |
Lecture Notes in Computer Science |
Abbreviated Series Title |
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| Series Volume |
7521 |
Series Issue |
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Edition |
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ISBN |
978-3-642-32942-5 |
Medium |
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Conference |
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| Notes |
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Approved |
yes |
| Call Number |
Sapienza @ mari @ Mari2012 |
Serial |
99 |
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| Author |
Mari, Federico; Melatti, Igor; Salvo, Ivano; Tronci, Enrico |
| Title |
Synthesis of Quantized Feedback Control Software for Discrete Time Linear Hybrid Systems |
Type |
Conference Article |
| Year |
2010 |
Publication |
Computer Aided Verification |
Abbreviated Journal |
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| Volume |
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Issue |
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Pages |
180-195 |
| Keywords |
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| Abstract |
We present an algorithm that given a Discrete Time Linear Hybrid System returns a correct-by-construction software implementation K for a (near time optimal) robust quantized feedback controller for along with the set of states on which K is guaranteed to work correctly (controllable region). Furthermore, K has a Worst Case Execution Time linear in the number of bits of the quantization schema. |
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Thesis |
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| Publisher |
Springer Berlin / Heidelberg |
Place of Publication |
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Editor |
Touili, T.; Cook, B.; Jackson, P. |
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Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
Lecture Notes in Computer Science |
Abbreviated Series Title |
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| Series Volume |
6174 |
Series Issue |
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Edition |
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Expedition |
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Conference |
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| Notes |
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Approved |
yes |
| Call Number |
Sapienza @ mari @ cav2010 |
Serial |
16 |
| Permanent link to this record |
