DATABASE FUNDAMENTALS
DATA WAREHOUSING AND DATA MINING
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Hash-based techniques
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Transaction Increases
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Sampling
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Cleaning
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Detailed explanation-1: -Hashing technique is used to improve the efficiency of the apriori algorithm. it work by creating a dictionary (hash table) that stores the candidate item sets as keys, and the number of appearances as the value. Initialization start with zero and Increment the counter for each item set that you see in the data.
Detailed explanation-2: -Explanation: From the following options, all of the above i.e., hash-based techniques, transaction reduction and partitioning are the techniques that can be used to improve the efficiency of apriori algorithm.
Detailed explanation-3: -In this algorithm, each transaction counting all the 1-itemsets. At the same time all the possible 2-itemsets in the current transaction are hashed to a hash table. It uses a hash table to reduce the number if candidate itemsets. When the support count is established the algorithm determines the frequent itemsets.
Detailed explanation-4: -itemsets can be selected. The first algorithm based on CGB strategies is Apriori algorithm proposed by Agrawal in 1994[1]. Pattern-Growth-Based(PGB) strategy.