A Survey on Mining Frequent Itemsets over Uncertain Databases

PhD Qualifying Examination


Title: "A Survey on Mining Frequent Itemsets over Uncertain Databases"

by

Mr. Yongxin Tong


Abstract:

In recent years, due to the wide applications of uncertain data, mining 
frequent itemsets over uncertain databases has attracted much attention. 
In uncertain databases, the support of an itemset is a random variable 
instead of a fixed occurrence counting of this itemset. Thus, unlike the 
corresponding problem in deterministic databases where the frequent 
itemset has a unique definition, the frequent itemset under uncertain 
environments has two different definitions so far. The first definition, 
referred as the expected support-based frequent itemset, employs the 
expectation of the support of an itemset to measure whether this itemset 
is frequent. The second definition, referred as the probabilistic frequent 
itemset, uses the probability of the support of an itemset to measure its 
frequency. Thus, existing work on mining frequent itemsets over uncertain 
databases is divided into two different groups and no study is conducted 
to comprehensively compare the two different definitions. In addition, 
since no uniform experimental platform exists, current solutions for the 
same definition even generate inconsistent results. In this survey, we 
firstly aim to clarify the relationship between the two different 
definitions. Through extensive experiments, we verify that the two 
definitions have a tight connection and can be unified together when the 
size of data is large enough. Secondly, we provide baseline 
implementations of eight existing representative algorithms and test their 
performances with uniform measures fairly. Finally, according to our 
experimental evaluations over many different benchmark data sets, we 
clarify several existing inconsistent conclusions and discuss some new 
findings.


Date:                   Monday, 3 September 2012

Time:                   1:30pm - 3:30pm

Venue:                  Room 3501
                         lifts 25/26

Committee Members:	Dr. Lei Chen (Supervisor)
                         Prof. Frederick Lochovsky (Chairperson)
 			Dr. Raymond Wong
 			Dr. Ke Yi


**** ALL are Welcome ****