@inproceedings{PODS-2007-ZhangG,
	author        = "Linfeng Zhang and Yong Guan",
	booktitle     = "{Proceedings of the 26th Symposium on Principles of Database Systems}",
	doi           = "10.1145/1265530.1265562",
	isbn          = "978-1-59593-685-1",
	pages         = "225--232",
	publisher     = "{ACM}",
	title         = "{Variance estimation over sliding windows}",
	year          = 2007,
}