TY - GEN
T1 - The Frequent Items Problem, under Polynomial Decay, in the Streaming Model
AU - Feigenblat, Guy
AU - Itzhaki, Ofra
AU - Porat, E.
N1 - Place of conference:Finland
PY - 2009
Y1 - 2009
N2 - We consider the problem of estimating the frequency count of data stream elements under polynomial decay functions. In these settings every element arrives in the stream is assigned with a time decreasing weight, using a non increasing polynomial function. Decay functions are used in applications where older data is less significant \ interesting \ reliable than recent data. We propose 3 poly-logarithmic algorithms for the problem. The first one, deterministic, uses O(1ϵ2logN(loglogN+logU))O(1ϵ2logN(loglogN+logU)) bits. The second one, probabilistic, uses O(1ϵ2log1ϵδlogN)O(1ϵ2log1ϵδlogN) bits and the third one, deterministic in the stochastic model, uses O(1ϵ2logN)O(1ϵ2logN) bits. In addition we show that using additional additive error can improve, in some cases, the space bounds. This variant of the problem is important and has many applications. To our knowledge it was never studied before.
AB - We consider the problem of estimating the frequency count of data stream elements under polynomial decay functions. In these settings every element arrives in the stream is assigned with a time decreasing weight, using a non increasing polynomial function. Decay functions are used in applications where older data is less significant \ interesting \ reliable than recent data. We propose 3 poly-logarithmic algorithms for the problem. The first one, deterministic, uses O(1ϵ2logN(loglogN+logU))O(1ϵ2logN(loglogN+logU)) bits. The second one, probabilistic, uses O(1ϵ2log1ϵδlogN)O(1ϵ2log1ϵδlogN) bits and the third one, deterministic in the stochastic model, uses O(1ϵ2logN)O(1ϵ2logN) bits. In addition we show that using additional additive error can improve, in some cases, the space bounds. This variant of the problem is important and has many applications. To our knowledge it was never studied before.
UR - https://scholar.google.co.il/scholar?q=The+Frequent+Items+Problem%2C+under+Polynomial+Decay%2C+in+the+Streaming+Model&btnG=&hl=en&as_sdt=0%2C5
M3 - Conference contribution
BT - International Symposium on String Processing and Information Retrieval
A2 - Karlgren, Jussi
A2 - Tarhio, Jorma
A2 - Hyyrö, Heikki
PB - Springer Berlin Heidelberg
ER -