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From: Khalid Iqbal on 18 Jan 2010 12:30
Dear Friends
I need to implement apriori algorithm in Matlab. For this purpose, I using 5 attrubutes such as
A B C D E
T1 1 0 1 0 0
T2 1 1 1 0 1
T3 0 1 0 1 1
T4 1 1 1 0 1
T5 1 1 1 1 1
T6 0 1 0 1 0
The attributes represents the presence or absence of their occurence in a transaction. the minimum support is set (e.g. min_support=4) and support of each attribute is calculated in order to generate candidate set. support(A)=4, Support(B)=5, Support(C)=4,Support(D)=3 and Support(E)=4. SO we take those attributes in the next step which support is more than the min_support. Thus D is eliminated.
So culumns left are

A B C E
T1 1 0 1 0
T2 1 1 1 1
T3 0 1 0 1
T4 1 1 1 1
T5 1 1 1 1
T6 0 1 0 0
Now check the support(AB), Support(AC), support(AE), Support(BC), Support(BE) and support(CE). This can be checked using AND operator. If the suppport calculated is more or equal to the min_support then the attributes satisfying the min_spport threshold will go in the next round.
Now the support(ABC), Support(ABE) and Support(BCE will be checked against the min_support.
Finally support(ABCE) will checked against the min_support.

Finally Association Rules will be displayed as below.
Rule# Assciation Rules Support Confidence =Support(AuB)/Support(A)
1 A==> B 40% 75%
2 A,B ==> E 50% 82%
..... .......... ...... .......
...... .......... ...... .......
..... .......... ...... ........

Please if someone know about this implementation in Matlab. Let me know the code in Matlab.

Thanks in advance

Khalid
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