www-ai.cs.tu-dortmund.de/LEHRE/FACHPROJEKT/SS12/paper/counting/gothals2007.pdf
the sliding win- dow model [3, 6, 7, 8, 10, 12], the time fading model [9], and the landmark model [7, 8, 13]. The different frequency measures are illustrated in Figure 7. The bottom line reports the probability [...] + 1) = 1/1. At timestamp 8, something interesting hap- pens. S7 = [(2, 3), (6, 2)], corresponding with stream 〈b |a a a b |a a〉. Update(S7, {b}) will yield S8 = [(2, 5)], and not [(2, 3), (6, 2)]. Because [...] 106 5 106 6 106 7 106 8 106 9 106 1 107
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0 100 1 106 2 106 3 106 4 106 5 106 6 106 7 106 8 106 9 106 …
