Subject:Data Mining Consider the following set of candidate item sets: { 1 , 2 ,
ID: 663157 • Letter: S
Question
Subject:Data Mining
Consider the following set of candidate item sets:
{1, 2, 3}, {1, 2, 6}, {1, 3, 4}, {2, 3, 4}, {2, 4, 5}, {3, 4, 6}, {4, 5, 6}, {7, 2, 8}, {-1, 10, 10}
Construct a hash tree for the above candidate 3-itemsets. Assume the tree uses a hash function where the sum of the values in the left node less than the sum of the values in the right node. A candidate k-item set is inserted into the tree by hashing on each successive item in the candidate and then following the appropriate branch of the tree according to the hash value. Once a leaf node is reached, the candidate is inserted based on the rule previous stated.
What is the support and confidence pruning rule (describe ? how it is used, why it is used, pros and cons, and when it is used.)
Explanation / Answer
The rule X ?Y holds with support s if s% of transactions in D contain X ? Y.
Rules that have a s greater than a user-specified support is said to have minimumsupport.
The rule X ?Y holds with support s if s% of transactions in D contain X ? Y.
Rules that have a s greater than a user-specified support is said to have minimumsupport