Table 1 Notation.
From: Incremental high average-utility itemset mining: survey and challenges
Notation | Meaning |
|---|---|
I | A set of m items,I = {i1, i2, …, im}, where each item ij has a profit value pj |
DB | An original quantitative database, DB = {T1, T2, …, Tn}, in which each transaction is a subset of I, with purchase quantities for each item |
DBn+ | A set of new transactions, DBn = {t1, t2, …, tq}, in which each transaction includes a subset of items, with purchase quantities |
TID | Each transaction Tn ∈ D has a unique transaction identifier (TID) |
X | A k-itemset containing k distinct items {i1, i2, …, ik} |
u(ij, Tp) | The utility of an item ij in a transaction Tp |
u(Tp) | The sum of the utilities of items in a transaction Tp |
tuDB | The total utility tuDB of a database DB |
au(X,Tp) | The average utility of X in Tp |
au(X) | The average utility of X in DB |
HAUI | High-average-utility Itemset |
mu(Tp) | The maximum utility of transaction Tp |
auub(ij) | The average-utility upper-bound (AUUB) of item ij |
HAUUBIDB | High average-utility upper bound itemset |
PAUUBIDB | Pre-large average-utility upper-bound itemset |
HAUIUDB | An itemset X is classified as an HAUIUDB in the updated (DB + DBn) database |
