In this section, we will study the problem of predicting whether a particular banknote is genuine or whether it has been forged. The banknote authentication data set is hosted at https://archive.ics.uci.edu/ml/datasets/banknote+authentication. The creators of the data set have taken specimens of both genuine and forged banknotes and photographed them with an industrial camera. The resulting grayscale image was processed using a type of time-frequency transformation known as a wavelet transform. Three features of this transform are constructed, and along with the image entropy, they make up the four features in total for this binary classification task.