Abstract: Training a machine learning model includes selecting a subset of training transactions from a plurality of training transactions to be used for classifying transactions as either fraudulent or genuine, and classifying transactions as either fraudulent or genuine. Additionally, selecting the subset of training transactions includes clustering the plurality of training transactions into a plurality of clusters based on a similarity measure. Each training transaction includes an indication whether the training transaction is fraudulent or genuine. Further, selecting the subset of training transactions includes selecting a first proportion of the training transactions of a cluster of training transactions for the subset of training transactions if the cluster comprises at least one fraudulent training transaction, and selecting a second proportion of the training transactions of a cluster of training transactions for the subset of training transactions if the cluster is free of fraudulent training transactions.

Abstract: A golf club cleaning apparatus having: a housing; a water supply pipe; a waste water pipe; a top opening permitting access to: a first axle associated with a first brush, and a second axle associated with a second brush; the axles being associated with compressible elements biasing the first axle and the second axle and thus the brushes towards each other; the first brush and the second brush being configured to engage in a rotational movement via a motor; and a plurality of sprinklers associated with the water supply pipe configured to discharge water to the brushes; a water trap connected to the waste water pipe to drain waste water out of the apparatus; means for driving the rotational movement; and a card reader configured to process a payment, and associated with a logic configured to restrict an initiation of a cleaning procedure until the payment is processed.

Abstract: A golf club cleaning apparatus having: a housing; a water supply pipe; a waste water pipe; a top opening permitting access to: a first axle associated with a first brush, and a second axle associated with a second brush; the axles being associated with compressible elements biasing the first axle and the second axle and thus the brushes towards each other; the first brush and the second brush being configured to engage in a rotational movement via a motor; and a plurality of sprinklers associated with the water supply pipe configured to discharge water to the brushes; a water trap connected to the waste water pipe to drain waste water out of the apparatus; means for driving the rotational movement; and a card reader configured to process a payment, and associated with a logic configured to restrict an initiation of a cleaning procedure until the payment is processed.