@TECHREPORT{R-96-03,
PSURL = {/publications/cgi-bin/tr-fetch.pl?r-96-03+ps},
ABSTRACTURL = {/publications/cgi-bin/tr-fetch.pl?r-96-03+abstr},
ABSTRACT = {A time sequence is a discrete sequence of values, e.g. temperature
 measurements, varying over time. By applying an interpolation 
function a discrete time sequence can be coerced into a continues
 function over time, F(t), which we call an interpolated time sequence.
 Many applications need to deal with querying interpolated time 
sequences. Simple queries involve finding F(t') for a given time 
point t', which are easy to support using regular ordered indexes.
 The main contribution of this paper is a new index structure, 
the interpolation index (IP-index) which supports efficient retrievals
 of those time points t where F(t) = v' for a given v', i.e. efficient
 computation of interpolated inverse queries, F-1(v'). Performance 
measures show that the IP-index radically improves the search time
 for interpolated inverse queries. It is also shown that the insertion
 time of the IP-index for most periodic time sequences has an upper
 limit, and for largely monotonic sequences it is logarithmic. 

Keywords: time sequences, indexing, temporal databases.
},
NUMBER = {R-96-03},
INSTITUTION = ida,
ADDRESS = idaaddr,
YEAR = {1996},
AUTHOR = {Lin, Ling and Risch, Tore and Badal, Dushan},
EMAIL = {linli@ida.liu.se},
TITLE = {Indexing Interpolated Time Sequences
}