# Confusions about fp tree growth numerical-:

If fcam=3,Would conditional fp tree still be c=4 or what would it be?

My guess is that it should be f=3,c=4,a=3,m=3. Am I right? Or what else would it be? Please guide.

Also, in this below figure(same figure but more elaborated), how is the conditional fp tree of p-: c=3?? How

My reasoning-:

The conditional pattern base of p is fcam=2 and cb=1. fcma lies in 1 branch whereas cb lies in another branch.

## 1 Answer

I will first explain Example2 and then go for first question. Also assuming minimum support = 3.

Q: How is conditional fp tree of p-: c=3?
A: draw p's conditional FP-tree. Remember FP-growth algorithm is Divide and conquer approach. We do same step of

1. creating 1-itemset.
2. order frequent items in frequency descending order.

1. scan DB again, construct FP-tree. This time there is single node in FP-tree.

This new fp-tree has single node. That's give {c} with frequency 3.

Now, for your first question, for fcam:3, that branch following must have node p:3. Then yes, c=4 will be one of the frequent items. But there will be few other frequent patterns too.

• ok thanks. i was confused because there was another slide which for qn2) was suggesting that it should be empty set as there is no common path between 2 branches fcamp and cbp, that is why I was confused. Aug 29, 2021 at 11:30