Example computer executable instructions for determining a consumer's offer eligibility using a predicate logic tree against sets of input data are provided. In particular, the disclosed examples recite a rewards engine capable of determining a consumer's offer eligibility using a predicate logic tree against sets of input data. The rewards engine applies rules that are relevant to a particular deal offered by a retail establishment to the consumer's records to determine the consumer's offer eligibility. In some examples, the rewards engine sorts or partially sorts some or all of the consumer's records to determine the consumer's offer eligibility.