dm.cs.tu-dortmund.de/mlbits/frequent-pattern-apriori-algorithm/
Apriori Algorithm – Lecture Notes
3), (1~ 2~ 4), (1~ 3~ 4), (1~ 3~ 5), (2~ 3~ 4)\}\)
After join:
\(\{ (1~ 2~ 3~ 4), (1~ 3~ 4~ 5)\}\)
pruning step:
remove \((1~ 3~ 4~ 5)\) because \((3~ 4~ 5), (1~ 4~ 5) \not\in F_3\)
⇝
\(C_4 = \{ (1~ 2~ [...] first \(k-2\) elements
\(p \in F_{k-1}:\)
( 1 2 3)
\(\downarrow\)
( 1 2 3 4) \(\in C_k\)
\(\uparrow\)
\(q \in F_{k-1}:\)
( 1 2 4)
Step 2: Pruning
Remove all candidate itemsets that have a subset of size [...] 2~ 3~ 4)\}\)
Apriori: Example with \(\textit{minsupp}=50\%\)
TID
Items
1
A B C D E
2
A B E
3
A B D E
4
A B D
5
B C D E
6
B D E
7
A B C E
8
C D
9
A B D
10
A B D
scan \(D\)
\(\longrightarrow\)
\(C_1\)
{ …
