The analysis of the beer and diapers is famous as a success of data mining . Associations analysis is a method of this case.
Associations analysis is also called "Market-basket analysis".
Associations analysis tells us the combination of things occurring frequently.
The combination is, for example, the probability that "If A occurs, B occurs" and the probability that "If B occurs, A occurs".
It is interesting that both probabilities are not always same. For example, "A is a bed and B is a sheet."
Complicated probability is also calculated. For example, "if A and B occur, C occur."
When one variable is considered as Y and output about the variable is collected, such analysis is similar to Rough sets analysis (RSA).
RSA studies the difference of the effect of the category of Y. It is a difference between RSA and Associations analysis.
Associations analysis is a study of cause and effect.
Generally an effect is a cause of other effects. Or causes of an effect are not always one. Bayesian network is a method to study such structure.