ch5 mining frequent patterns associations and correlations l.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Ch5 Mining Frequent Patterns, Associations, and Correlations PowerPoint Presentation
Download Presentation
Ch5 Mining Frequent Patterns, Associations, and Correlations

Loading in 2 Seconds...

play fullscreen
1 / 9

Ch5 Mining Frequent Patterns, Associations, and Correlations - PowerPoint PPT Presentation


  • 228 Views
  • Uploaded on

Ch5 Mining Frequent Patterns, Associations, and Correlations. Dr. Bernard Chen Ph.D. University of Central Arkansas Fall 2010. What Is Frequent Pattern Analysis?. Frequent pattern : a pattern (a set of items, subsequences, substructures, etc.) that occurs frequently in a data set

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Ch5 Mining Frequent Patterns, Associations, and Correlations' - mari


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
ch5 mining frequent patterns associations and correlations

Ch5 Mining Frequent Patterns, Associations, and Correlations

Dr. Bernard Chen Ph.D.

University of Central Arkansas

Fall 2010

what is frequent pattern analysis
What Is Frequent Pattern Analysis?
  • Frequent pattern: a pattern (a set of items, subsequences, substructures, etc.) that occurs frequently in a data set
  • First proposed by Agrawal, Imielinski, and Swami [AIS93] in the context of frequent itemsets and association rule mining
what is frequent pattern analysis3
What Is Frequent Pattern Analysis?
  • Motivation: Finding inherent regularities in data
    • What products were often purchased together? bread and milk?
    • What are the subsequent purchases after buying a PC?
    • What kinds of DNA are sensitive to this new drug?
    • Can we automatically classify web documents?
  • Applications
    • Basket data analysis, cross-marketing, catalog design, sale campaign analysis, Web log (click stream) analysis, and DNA sequence analysis.
association rules5
Association Rules
  • support, s, probability that a transaction contains X  Y
  • confidence, c,conditional probability that a transaction having X also contains Y
association rules6
Association Rules
  • Let’s have an example
    • T100 1,2,5
    • T200 2,4
    • T300 2,3
    • T400 1,2,4
    • T500 1,3
    • T600 2,3
    • T700 1,3
    • T800 1,2,3,5
    • T900 1,2,3
the apriori algorithm
The Apriori Algorithm
  • Pseudo-code:

Ck: Candidate itemset of size k

Lk : frequent itemset of size k

L1 = {frequent items};

for(k = 1; Lk !=; k++) do begin

Ck+1 = candidates generated from Lk;

for each transaction t in database do

increment the count of all candidates in Ck+1 that are contained in t

Lk+1 = candidates in Ck+1 with min_support

end

returnkLk;

exercise
Exercise
  • A dataset has five transactions, let min-support=60% and min_support=80%
  • Find all frequent itemsets using Apriori