TY  - CONF
ID  - boettcher2009pkdd
T1  - A Condensed Representation of Itemsets for Analyzing their Evolution over Time
A1  - Böttcher, Mirko
A1  - Spott, Martin
A1  - Kruse, Rudolf
TI  - 11th European Conference on Principles and Practice of Knowledge Discovery in Databases (PKDD2009)
T3  - Lecture Notes in Artificial Intelligence (LNAI)
Y1  - 2009
PB  - Springer
N1  - (to appear)
N2  - Driven by the need to understand change within domains
there is emerging research on methods which aim at analyzing
how patterns and in particular itemsets evolve over time.
In practice, however, these methods suffer from the problem
that many of the observed changes in itemsets are temporally
redundant in the sense that they are the side-effect of changes in
other itemsets, hence making the identification of the fundamental
changes difficult. As a solution we propose temporally closed itemsets,
a novel approach for a condensed representation of itemsets which is
based on removing temporal redundancies. We investigate how our approach
relates to the well-known concept of closed itemsets if the latter
would be directly generalized to account for the temporal dimension.
Our experiments support the theoretical results by showing that the
set of temporally closed itemsets is significantly smaller than the
set of closed itemsets.
ER  -