In data mining, association rule learning is a popular and well researched method for discovering interesting relations between variables in large databases. It is intended to identify strong rules discovered in databases using different measures of interestingness. Based on the concept of strong rules, Rakesh Agrawal et al [1] introduced association rules for discovering regularities between products in large-scale transaction data recorded by point-of-sale (POS) systems in supermarkets. For example, the rule {onions, potatoes}=>{burger} found in the sales data of a supermarket would indicate that if a customer buys onions and potatoes together, he or she is likely to also buy hamburger meat. Such information can be used as the basis for decisions about marketing activities such as: e.g. promotional pricing or product placements. In addition to the above example from market basket analysis association rules are employed today in many application areas including Web usage miningintrusion detectionContinuous production, and bioinformatics. As opposed to sequence mining, association rule learning typically does not consider the order of items either within a transaction or across transactions.

There are many different association rules can be derived from even a very small dataset, interest is restricted to those that apply to a reasonably large number of instances and have a reasonably high accuracy on the instances to which they apply.

Useful Concepts

Suppose there are two different products A and B:

association rule

Thus, the information for example Keyboard -> Mouse [support=6%, confidence=70%] means:

  • About 6% of customers purchase a keyboard and mouse;
  • The probability of customers who purchase a keyboard also tends to buy a mouse at the same time is 70%;

References & Resources