Association.pptx

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Association Analysis is just elementary probability with new names
0.3
Pr{B}=0.3
A
Pr{A}
=0.5
Pr{A and B}
= 0.2
B
0.1
0.4
0.3+0.2+0.1+0.4 = 1.0
Rule B=> A “people who buy B will buy A”
Support:
Support= Pr{A and B} = 0.2
A
0.3
B
0.2 0.1
0.4
Pr{A}=0.5= Expected confidence if there is no
relation to B. In other words, under independence,
Pr{A|B}=Pr{A} = 0.5.
Confidence:
Confidence = Pr{A|B}=Pr{A and B}/Pr{B}=2/3
?? Is the confidence in B=>A the same as the
confidence in A=>B?? (yes, no)
Lift:
Lift = confidence / E{confidence} =
(2/3) / (1/2) = 1.33 Gain = 33%
Marketing A to the 30%
of people who buy B will
result in 33% better sales
than marketing to a random
30% of the people.
Link Graph:
Color and line thickness are
proportional to confidence
Link Graph from Bank data
in Notes

Results
ViewrulesLink Graph
Right click, Graph Properties
 links Show Threshold
Slider
Link Graph:
Circle size proportional
to count in data
Color and line thickness are
proportional to confidence
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