Statistically Sound Associations
One limitation of the standard approach to discovering associations is that by searching massive numbers of possible associations to look for collections of items that appear to be associated, there is a large risk of finding many spurious associations. These are collections of items that co-occur with unexpected frequency in the data, but only do so by chance. For example, suppose we are considering a collection of 10,000 items and looking for rules containing two items in the left-hand-side and 1 item in the right-hand-side. There are approximately 1,000,000,000,000 such rules. If we apply a statistical test for independence with a significance level of 0.05 it means there is only a 5% chance of accepting a rule if there is no association. If we assume there are no associations, we should nonetheless expect to find 50,000,000,000 rules. Statistically sound association discovery controls this risk, in most cases reducing the risk of finding any spurious associations to a user-specified significance level.
Read more about this topic: Association Rule Learning
Famous quotes containing the words sound and/or associations:
“How little it takes to make us happy! The sound of a bagpipe.—Without music life would be a mistake. The German even imagines God as singing songs.”
—Friedrich Nietzsche (1844–1900)
“Wild as it was, it was hard for me to get rid of the associations of the settlements. Any steady and monotonous sound, to which I did not distinctly attend, passed for a sound of human industry.... Our minds anywhere, when left to themselves, are always thus busily drawing conclusions from false premises.”
—Henry David Thoreau (1817–1862)