Abstract | We consider the problem of querying largescale multidimensional time series data to discover events
of interest, test and validate hypotheses, or to associate
temporal patterns with specific events. This type of data
currently dominate most other types of available data,
and will very likely become even more prevalent in the
future given the current trends in collecting time series of
business, scientific, demographic, and simulation data. The
ability to explore such collections interactively, even at a
coarse level, will be critical in discovering the information
and knowledge embedded in such collections. We develop
indexing techniques and search algorithms to efficiently
handle temporal range value querying of multidimensional
time series data. Our indexing uses linear space data
structures that enable the handling of queries in I/O time
that is essentially the same as that of handling a single time
slice, assuming the availability of a logarithmic number of
processors as a function of size of the temporal window. A
data structure with provably good bounds is also presented
for the case when the number of multidimensional objects
is relatively small. These techniques improve significantly
over standard techniques for either serial or parallel
processing, and are evaluated by extensive experimental
results that confirm their superior performance.
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