How is the support of an association rule estimated?

The support of an association rule is a measure that indicates how often a specific item or set of items appears in a dataset relative to the entire set of transactions. It can be computed by taking the number of transactions that contain the item or itemset and dividing it by the total number of transactions in the dataset. This provides a clear picture of the frequency with which that rule is fulfilled, indicating its overall significance.

In the context of association rule mining, support is crucial because it helps in identifying the most relevant rules that can be considered for further analysis and decision-making. It serves as a foundational metric that allows practitioners to filter out rules that occur infrequently, thereby increasing the confidence that the rule conveys meaningful information about relationships and patterns within the data.

Other options may touch on related concepts, such as transaction frequency or the confidence levels of rules, but these do not specifically define how support itself is calculated or understood. Transaction frequency, while related, focuses more on the number of times transactions occur without the comparative context needed to define support as a percentage of all transactions. Confidence levels relate to the reliability of an association rule but do not address the estimation of support directly.