Spam email detection is basically a machine learning classification problem. We herein get started with learning important concepts of machine learning classification. Classification is one of the main instances of supervised learning in machine learning. Given a training set of data containing observations and their associated categorical outputs, the goal of classification is to learn a general rule that correctly maps the observations (also called features) to the targeted categories. In another word, a trained classification model will be generated by learning from the features and targets of training samples, as shown in the diagram below. When new or unseen data comes in, it will be able to determine their desired memberships. Class information will be predicted based on the known input features using the trained classification model.
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