Abstract

over imprecisely represented objects. Such objects are used either because they are much smaller in size than the precise ones (e.g., compressed versions of time series), or as imprecise replicas of fast-changing objects across the network (e.g., interval approximations for time-varying sensor readings). It may be impossible to determine whether an imprecise object meets the selection predicate. Additionally, the objects appearing in the output are also imprecise. Retrieving the precise objects themselves (at additional cost) can be used to increase the quality of the reported answer.

Citations