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Can we choose whether we want to use confidence or lift?
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From: 
ANONYMOUS 
Date: 
Thu 28th May, 12:33pm 
Actions: 



Hey,
When I was trying to use lift to find rules/patterns for associated attributes, it
wouldn’t have income bracket on the right hand side. However if I used car = True and
tried to find the confidence, I would see income bracket on the right hand side. My
question is that for step 1, ‘association rule mining’, can we just use confidence to
justify the interestingness of the rule and why we chose it? Or is there another way
to get lift to work?
As well as, when I used car = True and tried to find the confidence, I would see
income bracket on the right hand side, but it only happens to be <=50K. Should I
change the min lower bound and upper bound or would there be a way to combat this?
Thanks

Can we choose whether we want to use confidence or lift?


From: 
Zeyi W. 
Date: 
Thu 28th May, 2:57pm 
Actions: 



You can use confidence instead of lift.
For the second problem, you can (1) set a very small confidence threshold and a very large
number of rules (e.g. 1000), and then search for the rules you like; (2) construct a data set
only having income>50k and do the rule mining, where you will have 100% confidence and you can
use support to rank the rules; (3) balance the data sets, so that both income>50k and
income<=50 have similar number of instances, and perform the rule mining.
Any of the above three approaches is fine.

Can we choose whether we want to use confidence or lift?


From: 
ANONYMOUS O.P. 
Date: 
Thu 28th May, 10:53pm 
Actions: 



"Zeyi Wen" <ze*i*w*[email protected]*a*e*u*a*> wrote:
> You can use confidence instead of lift.
>
> For the second problem, you can (1) set a very small confidence threshold and a very large
> number of rules (e.g. 1000), and then search for the rules you like; (2) construct a data set
> only having income>50k and do the rule mining, where you will have 100% confidence and you can
> use support to rank the rules; (3) balance the data sets, so that both income>50k and
> income<=50 have similar number of instances, and perform the rule mining.
>
> Any of the above three approaches is fine.
Thank you for your help Zeyi.
Having taken approach (2), should we just use the minsupport that we get from Apriori to justify
interestingness when confidence is 100%? As well as, I find if I use lift, it tends to give me more
than one attribute on the right hand side but still includes income bracket >50K, would this still
be ok to interpret as patterns for income bracket?

Can we choose whether we want to use confidence or lift?


From: 
Zeyi W. 
Date: 
Fri 29th May, 11:29am 
Actions: 



Not the minsupport, but the support for the itemsets (which generate the rules). You may need to do some
searches to find out.
You should have only income bracket on the righthand side.

