Sciweavers

Share
ICDE
2009
IEEE

Forward Decay: A Practical Time Decay Model for Streaming Systems

12 years 1 months ago
Forward Decay: A Practical Time Decay Model for Streaming Systems
Temporal data analysis in data warehouses and data streaming systems often uses time decay to reduce the importance of older tuples, without eliminating their influence, on the results of the analysis. While exponential time decay is commonly used in practice, other decay functions (e.g. polynomial decay) are not, even though they have been identified as useful. We argue that this is because the usual definitions of time decay are "backwards": the decayed weight of a tuple is based on its age, measured backward from the current time. Since this age is constantly changing, such decay is too complex and unwieldy for scalable implementation. In this paper, we propose a new class of "forward" decay functions based on measuring forward from a fixed point in time. We show that this model captures the more practical models already known, such as exponential decay and landmark windows, but also includes a wide class of other types of time decay. We provide efficient algorit...
Graham Cormode, Vladislav Shkapenyuk, Divesh Sriva
Added 20 Oct 2009
Updated 20 Oct 2009
Type Conference
Year 2009
Where ICDE
Authors Graham Cormode, Vladislav Shkapenyuk, Divesh Srivastava, Bojian Xu
Comments (0)
books