TY - JOUR T1 - A Temporal Pattern Search Algorithm for Personal History Event Visualization JF - Knowledge and Data Engineering, IEEE Transactions on Y1 - 2012 A1 - Wang,T. D A1 - Deshpande, Amol A1 - Shneiderman, Ben KW - automaton-based approach KW - binary search KW - bit-parallel approach KW - data visualisation KW - electronic health records KW - event array KW - finite automata KW - interactive visualization program KW - Lifelines2 visualization tool KW - medical information systems KW - NFA approach KW - nondeterministic finite automaton KW - O(m2n lg(n)) problem KW - pattern matching KW - personal history event visualization KW - Shift-And approach KW - temporal pattern search algorithm KW - time stamp AB - We present Temporal Pattern Search (TPS), a novel algorithm for searching for temporal patterns of events in historical personal histories. The traditional method of searching for such patterns uses an automaton-based approach over a single array of events, sorted by time stamps. Instead, TPS operates on a set of arrays, where each array contains all events of the same type, sorted by time stamps. TPS searches for a particular item in the pattern using a binary search over the appropriate arrays. Although binary search is considerably more expensive per item, it allows TPS to skip many unnecessary events in personal histories. We show that TPS's running time is bounded by O(m2n lg(n)), where m is the length of (number of events) a search pattern, and n is the number of events in a record (history). Although the asymptotic running time of TPS is inferior to that of a nondeterministic finite automaton (NFA) approach (O(mn)), TPS performs better than NFA under our experimental conditions. We also show TPS is very competitive with Shift-And, a bit-parallel approach, with real data. Since the experimental conditions we describe here subsume the conditions under which analysts would typically use TPS (i.e., within an interactive visualization program), we argue that TPS is an appropriate design choice for us. VL - 24 SN - 1041-4347 CP - 5 M3 - 10.1109/TKDE.2010.257 ER -