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The space complexity of approximating the frequency moments

by Noga Alon, Yossi Matias, Mario Szegedy - JOURNAL OF COMPUTER AND SYSTEM SCIENCES , 1996
"... The frequency moments of a sequence containing mi elements of type i, for 1 ≤ i ≤ n, are the numbers Fk = �n i=1 mki. We consider the space complexity of randomized algorithms that approximate the numbers Fk, when the elements of the sequence are given one by one and cannot be stored. Surprisingly, ..."
Abstract - Cited by 845 (12 self) - Add to MetaCart
The frequency moments of a sequence containing mi elements of type i, for 1 ≤ i ≤ n, are the numbers Fk = �n i=1 mki. We consider the space complexity of randomized algorithms that approximate the numbers Fk, when the elements of the sequence are given one by one and cannot be stored. Surprisingly

Activity recognition from user-annotated acceleration data

by Ling Bao, Stephen S. Intille , 2004
"... In this work, algorithms are developed and evaluated to detect physical activities from data acquired using five small biaxial accelerometers worn simultaneously on different parts of the body. Acceleration data was collected from 20 subjects without researcher supervision or observation. Subjects ..."
Abstract - Cited by 515 (7 self) - Add to MetaCart
. Subjects were asked to perform a sequence of everyday tasks but not told specifically where or how to do them. Mean, energy, frequency-domain entropy, and correlation of acceleration data was calculated and several classifiers using these features were tested. Decision tree classifiers showed the best

Data Preparation for Mining World Wide Web Browsing Patterns

by Robert Cooley, Bamshad Mobasher, Jaideep Srivastava - KNOWLEDGE AND INFORMATION SYSTEMS , 1999
"... The World Wide Web (WWW) continues to grow at an astounding rate in both the sheer volume of tra#c and the size and complexity of Web sites. The complexity of tasks such as Web site design, Web server design, and of simply navigating through a Web site have increased along with this growth. An i ..."
Abstract - Cited by 567 (43 self) - Add to MetaCart
. An important input to these design tasks is the analysis of how a Web site is being used. Usage analysis includes straightforward statistics, such as page access frequency, as well as more sophisticated forms of analysis, such as finding the common traversal paths through a Web site. Web Usage Mining

Compressive sampling

by Emmanuel J. Candès , 2006
"... Conventional wisdom and common practice in acquisition and reconstruction of images from frequency data follow the basic principle of the Nyquist density sampling theory. This principle states that to reconstruct an image, the number of Fourier samples we need to acquire must match the desired res ..."
Abstract - Cited by 1441 (15 self) - Add to MetaCart
Conventional wisdom and common practice in acquisition and reconstruction of images from frequency data follow the basic principle of the Nyquist density sampling theory. This principle states that to reconstruct an image, the number of Fourier samples we need to acquire must match the desired

Space-time codes for high data rate wireless communication: Performance criterion and code construction

by Vahid Tarokh, Nambi Seshadri, A. R. Calderbank - IEEE TRANS. INFORM. THEORY , 1998
"... We consider the design of channel codes for improving the data rate and/or the reliability of communications over fading channels using multiple transmit antennas. Data is encoded by a channel code and the encoded data is split into n streams that are simultaneously transmitted using n transmit ant ..."
Abstract - Cited by 1782 (28 self) - Add to MetaCart
We consider the design of channel codes for improving the data rate and/or the reliability of communications over fading channels using multiple transmit antennas. Data is encoded by a channel code and the encoded data is split into n streams that are simultaneously transmitted using n transmit

Estimation of probabilities from sparse data for the language model component of a speech recognizer

by Slava M. Katz - IEEE Transactions on Acoustics, Speech and Signal Processing , 1987
"... Abstract-The description of a novel type of rn-gram language model is given. The model offers, via a nonlinear recursive procedure, a com-putation and space efficient solution to the problem of estimating prob-abilities from sparse data. This solution compares favorably to other proposed methods. Wh ..."
Abstract - Cited by 799 (2 self) - Add to MetaCart
, and it is a problem that one always encounters while collecting fre-quency statistics on words and word sequences (m-grams) from a text of finite size. This means that even for a very large data col-lection, the maximum likelihood estimation method does not allow Turing’s estimate PT for a probability of a

Approximate Frequency Counts over Data Streams

by Gurmeet Singh Manku, Rajeev Motwani - VLDB , 2002
"... We present algorithms for computing frequency counts exceeding a user-specified threshold over data streams. Our algorithms are simple and have provably small memory footprints. Although the output is approximate, the error is guaranteed not to exceed a user-specified parameter. Our algorithms can e ..."
Abstract - Cited by 418 (1 self) - Add to MetaCart
We present algorithms for computing frequency counts exceeding a user-specified threshold over data streams. Our algorithms are simple and have provably small memory footprints. Although the output is approximate, the error is guaranteed not to exceed a user-specified parameter. Our algorithms can

Comparison of parametric representations for monosyllabic word recognition in continuously spoken sentences

by Steven B. Davis, Paul Mermelstein - ACOUSTICS, SPEECH AND SIGNAL PROCESSING, IEEE TRANSACTIONS ON , 1980
"... Several parametric representations of the acoustic signal were compared as to word recognition performance in a syllable-oriented continuous speech recognition system. The vocabulary in-cluded many phonetically similar monosyllabic words, therefore the emphasis was on ability to retain phonetically ..."
Abstract - Cited by 1120 (2 self) - Add to MetaCart
generated using an efficient dynamic method, and test data were time registered wi th the templates. A set of ten mel-frequency cepstrum coefficients computed every 6 " 4 ms resulted in the best performance, namely 96.. 5 % and 9500 % recognition with each of two speakers.. The superior performance

Mega: molecular evolutionary genetic analysis software for microcomputers

by Sudhir Kumar, Koichiro Tamura, Masatoshi Nei - CABIOS , 1994
"... A computer program package called MEGA has been developed for estimating evolutionary distances, reconstructing phylogenetic trees and computing basic statistical quantities from molecular data. It is written in C+ + and is intended to be used on IBM and IBM-compatible personal computers. In this pr ..."
Abstract - Cited by 505 (10 self) - Add to MetaCart
A computer program package called MEGA has been developed for estimating evolutionary distances, reconstructing phylogenetic trees and computing basic statistical quantities from molecular data. It is written in C+ + and is intended to be used on IBM and IBM-compatible personal computers

Some Evidence on the Importance of Sticky Prices

by Mark Bils, Peter J. Klenow - JOURNAL OF POLITICAL ECONOMY , 2004
"... We examine the frequency of price changes for 350 categories of goods and services covering about 70 % of consumer spending, based on unpublished data from the BLS for 1995 to 1997. Compared with previous studies we find much more frequent price changes, with half of goods' prices lasting less ..."
Abstract - Cited by 741 (15 self) - Add to MetaCart
We examine the frequency of price changes for 350 categories of goods and services covering about 70 % of consumer spending, based on unpublished data from the BLS for 1995 to 1997. Compared with previous studies we find much more frequent price changes, with half of goods' prices lasting less
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