Lecture 4 Association Rules of Data Reasoning Dr.李晓瑜Xiaoyu Li Email:xiaoyuuestc@uestc.edu.cn http://blog.sciencenet.cn/u/uestc2014xiaoyu 2019-Spring SunData Group http://www.sundatagroup.org School of Information and Software Engineering,UESTC 1966 Copyright2019 by Xiaoyu Li
Dr.李晓瑜 Xiaoyu Li Email：xiaoyuuestc@uestc.edu.cn http://blog.sciencenet.cn/u/uestc2014xiaoyu 2019-Spring Lecture 4 Association Rules of Data Reasoning SunData Group http://www.sundatagroup.org/ School of Information and Software Engineering, UESTC Copyright © 2019 by Xiaoyu Li. 1
Topic 。Apriori Algorithm Improve of Apriori Algorithm 。FP-growth Algorithm Multilevel Association Rules Quantitative association Rules Multidimensional Association Rules 3 Copyright 2019 by Xiaoyu Li
Apriori Algorithm Improve of Apriori Algorithm FP-growth Algorithm Multilevel Association Rules Quantitative Association Rules Multidimensional Association Rules Copyright © 2019 by Xiaoyu Li. 3 Topic
Apriori Algorithm DATA 4 Copyright 2019 by Xiaoyu Li
Copyright © 2019 by Xiaoyu Li. 4 Apriori Algorithm
Apriori Principle Apriori principle: If an itemset is frequent,then all of its subsets must also be frequent Apriori principle holds due to the following property of the support measure: VX,Y:(XCY)→s(X)≥s(Y) Support of an itemset never exceeds the support of its subsets This is known as the anti-monotone property of support ATA 5 Copyright 2019 by Xiaoyu Li
5 Copyright © 2019 by Xiaoyu Li. Apriori Principle
Apriori Principle null AB AD AE BC BD BE CD CE DE Found to be Infrequent (ABC ABD ABE ACD ACE ADE BCD BCE BDE CDE ABCD ABCE ABDE ACDE BCDE Pruned supersets ABCDE ATA 6 Copyright 2019 by Xiaoyu Li
6 Copyright © 2019 by Xiaoyu Li. Apriori Principle