Association Rules: Infinity for Lift and Confidence

btibert
btibert New Altair Community Member
edited November 5 in Altair RapidMiner
Admittedly I am stumped as to why every single rule in my dataset has a value of infinity for lift.  What could the intuition of this possibly be?



If it helps, I have attached my dataset.

And the settings




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Comments

  • lionelderkrikor
    lionelderkrikor New Altair Community Member
    Hi @btibert,

    Unfortunately, I'm not an expert in "association rules" theory, but I found an answer element in the community : 

    https://community.rapidminer.com/discussion/50468/fp-growth-produced-infinite-value-for-association-rules

    Hope this helps,

    Regards,

    Lionel
  • IgorE
    IgorE New Altair Community Member
    I have a similar question about infinite confidence. 
    conf(X implies Y) = supp(X ∪Y) / supp(X) .
     supp(X ∪Y) = occurs(X ∪Y) / total_records
     supp(X) = occurs(X) / total_records

    so (if I'm not mistaken)

     conf(X implies Y) = occurs(X ∪Y) / occurs(X)

    How can it amount to infinity?

    I have two very similar datasets. RM generates very similar rules but in one case for the same rule, the confidence is 0.99 in another it's infinity.

    Please advise,
    Igor

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